Reading data:

mba.df <- read.csv(paste("file:///C:/Program Files/RStudio/Data/MBA Starting Salaries Data.csv", sep=""))
View(mba.df)
str(mba.df)
## 'data.frame':    274 obs. of  13 variables:
##  $ age     : int  23 24 24 24 24 24 25 25 25 25 ...
##  $ sex     : int  2 1 1 1 2 1 1 2 1 1 ...
##  $ gmat_tot: int  620 610 670 570 710 640 610 650 630 680 ...
##  $ gmat_qpc: int  77 90 99 56 93 82 89 88 79 99 ...
##  $ gmat_vpc: int  87 71 78 81 98 89 74 89 91 81 ...
##  $ gmat_tpc: int  87 87 95 75 98 91 87 92 89 96 ...
##  $ s_avg   : num  3.4 3.5 3.3 3.3 3.6 3.9 3.4 3.3 3.3 3.45 ...
##  $ f_avg   : num  3 4 3.25 2.67 3.75 3.75 3.5 3.75 3.25 3.67 ...
##  $ quarter : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ work_yrs: int  2 2 2 1 2 2 2 2 2 2 ...
##  $ frstlang: int  1 1 1 1 1 1 1 1 2 1 ...
##  $ salary  : int  0 0 0 0 999 0 0 0 999 998 ...
##  $ satis   : int  7 6 6 7 5 6 5 6 4 998 ...

Different data frames

  1. Those who disclosed their salary and satisfaction
mba1.df <- mba.df[which(mba.df$salary!= 998 & mba.df$salary!= 999 & mba.df$satis!= 998), ]
mba1.df
##     age sex gmat_tot gmat_qpc gmat_vpc gmat_tpc s_avg f_avg quarter
## 1    23   2      620       77       87       87  3.40  3.00       1
## 2    24   1      610       90       71       87  3.50  4.00       1
## 3    24   1      670       99       78       95  3.30  3.25       1
## 4    24   1      570       56       81       75  3.30  2.67       1
## 6    24   1      640       82       89       91  3.90  3.75       1
## 7    25   1      610       89       74       87  3.40  3.50       1
## 8    25   2      650       88       89       92  3.30  3.75       1
## 22   27   1      740       99       96       99  3.50  3.50       1
## 23   27   1      750       99       98       99  3.40  3.50       1
## 24   28   2      540       75       50       65  3.60  4.00       1
## 25   29   1      580       56       87       78  3.64  3.33       1
## 27   31   2      560       60       78       72  3.30  3.75       1
## 28   32   1      760       99       99       99  3.40  3.00       1
## 29   32   1      640       79       91       91  3.60  3.75       1
## 31   34   2      620       75       89       87  3.30  3.00       1
## 32   37   2      560       43       87       72  3.40  3.50       1
## 33   42   2      650       75       98       93  3.38  3.00       1
## 34   48   1      590       84       62       81  3.80  4.00       1
## 35   22   2      660       90       92       94  3.50  3.75       1
## 36   27   2      700       94       98       98  3.30  3.25       1
## 37   25   2      680       87       96       96  3.50  2.67       1
## 38   25   2      650       82       91       93  3.40  3.25       1
## 39   27   1      710       96       96       98  3.30  3.50       1
## 40   28   2      620       52       98       87  3.40  3.75       1
## 41   24   1      670       84       96       95  3.30  3.25       1
## 42   25   2      560       52       81       72  3.30  3.50       1
## 43   25   2      530       50       62       61  3.60  3.67       1
## 44   25   1      650       79       93       93  3.30  3.50       1
## 45   26   2      590       56       89       81  3.30  3.25       1
## 46   23   2      650       93       81       93  3.40  3.00       1
## 47   24   1      560       81       50       71  3.40  3.67       1
## 48   27   1      610       72       84       86  3.30  3.50       1
## 49   25   1      650       95       84       93  3.30  3.00       1
## 50   25   1      550       74       50       68  3.50  3.50       1
## 51   26   1      570       68       74       75  3.80  3.50       1
## 52   26   1      580       79       71       78  3.45  3.50       1
## 53   30   1      600       60       91       83  3.30  3.25       1
## 54   31   1      570       72       71       75  3.60  3.50       1
## 55   30   1      620       60       96       87  3.50  3.00       1
## 56   30   2      680       96       87       96  3.70  3.60       1
## 57   27   1      630       93       75       91  3.30  3.25       1
## 58   25   1      600       82       74       83  3.50  3.25       1
## 59   28   2      640       89       81       91  3.60  3.50       1
## 60   39   1      600       72       81       83  3.60  3.50       1
## 61   27   1      570       95       33       75  3.70  4.00       1
## 62   27   1      710       95       98       98  3.60  3.50       1
## 63   33   1      620       72       89       87  3.50  3.50       1
## 64   27   1      600       67       84       83  3.50  3.00       1
## 65   28   1      700       95       95       98  3.80  4.00       1
## 66   30   1      600       77       81       84  3.50  3.25       1
## 67   30   2      670       87       95       95  3.30  3.25       1
## 68   40   1      630       71       95       91  4.00  0.00       1
## 69   25   1      700       98       93       98  3.60  3.75       1
## 70   22   1      600       95       54       83  3.00  3.00       2
## 71   23   1      640       89       87       92  3.00  3.00       2
## 72   24   1      550       73       63       69  3.10  3.00       2
## 73   24   1      570       82       58       75  3.09  3.50       2
## 74   24   1      620       82       84       87  3.10  3.50       2
## 75   25   2      570       61       81       76  3.00  3.25       2
## 76   25   1      660       94       84       94  3.27  3.75       2
## 77   25   1      680       94       92       97  3.17  3.50       2
## 88   26   2      560       64       71       72  3.20  3.25       2
## 89   26   1      560       87       41       72  3.00  3.00       2
## 90   26   1      530       68       54       62  3.09  3.17       2
## 92   27   1      720       99       95       99  3.10  3.25       2
## 93   27   1      590       60       87       81  3.00  2.75       2
## 97   28   1      620       81       90       89  3.20  3.00       2
## 98   28   2      610       85       78       86  3.10  3.00       2
## 100  29   1      660       94       87       94  3.00  3.00       2
## 102  29   1      510       57       50       55  3.27  3.40       2
## 103  29   2      640       90       84       92  3.20  3.00       2
## 104  29   1      610       91       62       86  3.10  3.67       2
## 106  29   1      580       79       67       78  3.00  3.25       2
## 107  30   1      680       97       87       96  3.00  3.00       2
## 109  32   2      610       64       89       86  3.25  0.00       2
## 110  35   1      540       43       78       65  3.20  3.25       2
## 111  35   1      630       66       95       90  3.08  3.25       2
## 112  36   2      530       48       71       62  3.00  2.50       2
## 113  36   1      650       87       89       93  3.00  3.20       2
## 114  43   1      630       82       87       89  3.10  3.00       2
## 115  26   2      670       87       95       95  3.10  3.33       2
## 116  25   2      620       89       74       87  3.10  3.50       2
## 117  31   1      540       60       62       65  3.10  3.00       2
## 118  25   1      670       95       89       95  3.20  3.50       2
## 119  25   1      610       87       71       86  3.27  3.25       2
## 120  24   1      560       52       81       72  3.20  3.25       2
## 121  24   1      500       78       30       52  3.00  2.75       2
## 122  23   1      590       72       81       81  3.20  3.25       2
## 123  24   1      570       82       58       75  3.20  3.25       2
## 124  26   2      570       93       37       75  3.00  2.75       2
## 125  28   2      580       83       58       79  3.10  3.00       2
## 126  24   2      580       72       71       78  3.00  3.25       2
## 127  31   1      560       68       67       72  3.09  3.00       2
## 128  25   2      620       89       74       87  3.10  3.50       2
## 129  27   1      620       97       63       88  3.20  3.00       2
## 130  28   1      560       75       58       72  3.20  3.25       2
## 131  26   1      680       84       96       96  3.20  3.25       2
## 132  27   1      620       81       87       89  3.00  3.00       2
## 133  34   1      550       72       58       69  3.00  3.00       2
## 134  26   1      600       84       67       83  3.09  3.50       2
## 135  29   1      670       91       93       95  3.10  3.00       2
## 136  24   1      620       84       81       87  3.00  3.25       2
## 137  27   1      630       72       95       89  3.20  3.00       2
## 138  26   1      650       89       87       93  3.20  3.25       2
## 139  24   1      620       88       74       87  3.10  3.00       2
## 140  23   1      720       95       98       99  2.80  2.50       3
## 141  24   2      640       94       78       92  2.90  3.25       3
## 142  24   1      710       96       97       99  2.80  2.75       3
## 143  24   1      670       94       89       96  2.70  3.00       3
## 144  24   2      710       97       97       99  2.80  3.00       3
## 146  24   1      600       89       62       83  2.90  3.00       3
## 147  24   2      640       96       71       91  2.70  2.50       3
## 150  25   1      550       72       58       69  2.90  3.00       3
## 151  25   1      710       99       91       98  2.90  3.25       3
## 159  26   1      560       56       81       72  2.80  3.25       3
## 160  26   1      540       52       71       65  2.70  2.75       3
## 162  26   2      570       48       89       75  2.82  2.50       3
## 163  26   1      610       82       81       86  2.90  2.75       3
## 164  27   1      650       89       84       93  2.90  3.00       3
## 165  27   2      550       66       63       69  2.90  3.00       3
## 167  27   1      610       97       45       86  2.70  2.50       3
## 168  27   2      630       82       89       89  2.70  3.25       3
## 169  27   2      560       61       74       73  2.80  3.25       3
## 180  29   1      590       92       58       81  2.80  2.75       3
## 182  32   1      550       52       78       71  2.70  2.75       3
## 183  34   1      610       79       81       86  2.80  3.00       3
## 184  34   1      610       82       78       86  2.70  3.00       3
## 185  43   1      480       49       41       45  2.90  3.25       3
## 186  23   2      520       43       67       58  2.90  2.75       3
## 187  27   1      620       87       74       87  2.70  2.75       3
## 188  25   1      580       78       67       80  2.90  3.25       3
## 189  25   1      630       75       93       89  2.70  2.50       3
## 190  25   1      610       89       74       87  2.70  2.75       3
## 191  29   2      560       64       71       72  2.90  3.00       3
## 192  27   1      620       79       87       88  2.90  2.75       3
## 193  28   1      580       72       71       78  2.80  3.00       3
## 194  24   2      670       83       98       96  2.90  3.25       3
## 195  25   2      560       39       91       72  2.90  3.00       3
## 196  25   2      580       72       71       78  2.80  3.25       3
## 197  27   1      680       97       90       97  2.90  2.75       3
## 198  28   1      610       89       67       86  2.70  3.00       3
## 199  29   1      710       93       98       99  2.90  3.25       3
## 200  24   1      710       99       92       99  2.90  3.00       3
## 201  25   2      630       84       87       89  2.80  2.75       3
## 202  24   2      600       89       67       85  2.80  3.00       3
## 203  29   1      660       91       90       95  2.80  3.00       3
## 204  30   1      670       83       97       96  2.80  2.75       3
## 205  24   1      580       89       54       78  2.91  2.83       3
## 206  29   1      680       79       99       96  2.90  3.00       3
## 207  32   1      660       83       95       94  2.90  3.50       3
## 208  28   1      570       56       84       75  2.90  3.00       3
## 209  24   1      680       96       87       97  2.80  2.75       3
## 213  25   1      730       98       96       99  2.40  2.75       4
## 218  25   1      700       99       87       98  2.00  2.00       4
## 219  26   1      660       93       87       95  2.60  2.00       4
## 220  26   1      450       28       46       34  2.10  2.00       4
## 222  26   1      600       75       78       83  2.20  2.25       4
## 227  27   2      560       59       74       73  2.40  2.50       4
## 229  27   1      630       93       78       91  2.10  2.50       4
## 230  27   1      580       84       58       78  2.70  2.75       4
## 232  27   1      670       89       91       95  3.60  3.25       4
## 233  27   1      580       74       70       78  3.40  3.25       4
## 234  28   1      560       74       67       73  3.60  3.60       4
## 236  28   1      710       94       98       99  3.40  3.75       4
## 237  28   1      570       69       71        0  2.30  2.50       4
## 238  29   1      530       35       81       62  3.30  2.75       4
## 241  29   1      670       91       91       95  3.30  3.25       4
## 242  29   1      630       99       50       89  2.90  3.25       4
## 243  29   2      680       89       96       96  2.80  3.00       4
## 244  30   1      650       88       92       93  3.45  3.83       4
## 250  31   1      570       75       62       75  2.80  3.00       4
## 253  32   1      510       79       22       54  2.30  2.25       4
## 254  35   1      570       72       71       75  3.30  4.00       4
## 255  39   2      700       89       98       98  3.30  3.25       4
## 256  24   2      560       55       78       71  3.50  3.25       4
## 257  23   1      660       81       98       95  2.50  3.00       4
## 258  25   2      720       96       98       99  3.50  3.60       4
## 259  26   1      620       78       87       89  2.40  2.00       4
## 260  26   2      630       85       81       90  2.90  3.25       4
## 261  27   1      650       89       89       93  2.40  2.25       4
## 262  25   1      660       99       71       95  3.40  3.25       4
## 263  25   1      610       83       81       86  2.40  2.75       4
## 264  26   1      600       87       62       83  2.50  2.50       4
## 265  24   1      570       75       62       75  2.30  2.50       4
## 266  24   2      600       77       78       84  2.60  3.00       4
## 267  26   2      650       91       84       93  2.60  3.00       4
## 268  29   1      630       72       95       89  2.60  2.50       4
## 269  26   1      630       96       71       91  2.60  2.75       4
## 270  31   1      530       75       45       62  2.40  2.75       4
## 271  23   1      580       64       81       78  2.20  2.00       4
## 272  25   1      540       79       45       65  2.60  2.50       4
## 273  26   1      550       72       58       69  2.60  2.75       4
## 274  40   2      500       60       45       51  2.50  2.75       4
##     work_yrs frstlang salary satis
## 1          2        1      0     7
## 2          2        1      0     6
## 3          2        1      0     6
## 4          1        1      0     7
## 6          2        1      0     6
## 7          2        1      0     5
## 8          2        1      0     6
## 22         3        1      0     6
## 23         1        2      0     5
## 24         5        1      0     5
## 25         3        1      0     5
## 27        10        1      0     7
## 28         5        1      0     5
## 29         7        1      0     6
## 31         7        1      0     6
## 32         9        1      0     6
## 33        13        1      0     5
## 34        22        1      0     6
## 35         1        1  85000     5
## 36         2        1  85000     6
## 37         2        1  86000     5
## 38         3        1  88000     7
## 39         2        1  92000     6
## 40         5        1  93000     5
## 41         0        1  95000     4
## 42         1        1  95000     5
## 43         3        1  95000     3
## 44         1        1  96000     7
## 45         4        1  96000     5
## 46         2        1 100000     7
## 47         2        1 100000     6
## 48         6        1 100000     6
## 49         2        1 105000     7
## 50         3        1 105000     6
## 51         3        1 105000     6
## 52         2        1 105000     5
## 53         5        1 105000     6
## 54         6        1 105000     6
## 55         8        1 106000     7
## 56         6        1 106000     6
## 57         3        1 107500     5
## 58         3        1 108000     6
## 59         6        1 110000     5
## 60        16        1 112000     7
## 61         4        1 115000     5
## 62         1        1 115000     5
## 63        10        2 118000     7
## 64         3        1 120000     5
## 65         5        1 120000     5
## 66         5        1 120000     6
## 67         8        1 120000     6
## 68        15        1 146000     6
## 69         1        1 162000     5
## 70         1        1      0     5
## 71         2        1      0     7
## 72         0        2      0     5
## 73         2        1      0     6
## 74         1        1      0     5
## 75         3        1      0     4
## 76         2        1      0     5
## 77         2        1      0     6
## 88         3        1      0     6
## 89         3        1      0     6
## 90         4        2      0     5
## 92         5        1      0     5
## 93         3        1      0     6
## 97         4        1      0     6
## 98         5        1      0     6
## 100        1        1      0     6
## 102        5        1      0     5
## 103        3        1      0     5
## 104        7        1      0     5
## 106        4        1      0     6
## 107        4        1      0     5
## 109       11        1      0     7
## 110        8        1      0     5
## 111       12        1      0     5
## 112        7        1      0     5
## 113       18        1      0     6
## 114       16        1      0     5
## 115        1        1  82000     7
## 116        2        1  92000     5
## 117        8        1  93000     6
## 118        2        1  95000     6
## 119        3        1  95000     6
## 120        2        1  96000     7
## 121        2        1  96500     6
## 122        2        1  98000     6
## 123        2        1  98000     6
## 124        3        2  98000     5
## 125        5        2  99000     6
## 126        2        1 100000     5
## 127        4        1 100000     6
## 128        2        1 101000     5
## 129        3        1 103000     6
## 130        4        1 104000     5
## 131        3        1 105000     6
## 132        3        1 105000     5
## 133       16        1 105000     5
## 134        2        1 107000     5
## 135        6        1 112000     6
## 136        1        1 115000     6
## 137        4        1 115000     6
## 138        4        1 130000     7
## 139        2        1 145800     6
## 140        1        1      0     5
## 141        2        2      0     4
## 142        2        1      0     7
## 143        2        1      0     7
## 144        2        1      0     7
## 146        1        1      0     6
## 147        2        1      0     6
## 150        3        1      0     6
## 151        1        1      0     6
## 159        4        1      0     6
## 160        2        1      0     6
## 162        3        1      0     5
## 163        3        1      0     6
## 164        2        1      0     6
## 165        3        1      0     4
## 167        4        2      0     5
## 168        5        1      0     6
## 169        5        1      0     6
## 180        3        2      0     5
## 182        7        1      0     6
## 183       11        1      0     6
## 184       12        1      0     5
## 185       22        1      0     5
## 186        1        1  78256     5
## 187        3        1  88500     6
## 188        2        1  90000     7
## 189        2        1  90000     5
## 190        4        1  93000     6
## 191        5        1  95000     7
## 192        4        1  97000     7
## 193        3        1  97000     6
## 194        2        1  98000     7
## 195        2        1  98000     7
## 196        2        1  98000     6
## 197        2        2  98000     6
## 198        4        1  98000     7
## 199        7        1  98000     5
## 200        3        1 100000     6
## 201        2        1 100000     6
## 202        2        1 101000     6
## 203        8        1 101100     6
## 204        6        1 102500     5
## 205        2        1 105000     5
## 206        6        1 106000     6
## 207        2        2 107300     7
## 208        4        1 108000     6
## 209        2        1 112000     6
## 213        2        1      0     6
## 218        1        1      0     7
## 219        2        1      0     5
## 220        4        1      0     6
## 222        2        1      0     6
## 227        2        1      0     5
## 229        4        1      0     5
## 230        1        1      0     5
## 232        5        1      0     6
## 233        3        1      0     6
## 234        5        1      0     5
## 236        6        1      0     6
## 237        5        1      0     5
## 238        6        1      0     7
## 241        3        1      0     5
## 242        1        2      0     4
## 243        4        1      0     5
## 244        2        1      0     6
## 250        1        1      0     6
## 253        5        2      0     5
## 254        8        1      0     6
## 255        5        1      0     5
## 256        2        1  64000     7
## 257        2        1  77000     6
## 258        3        1  85000     6
## 259        2        1  85000     6
## 260        3        1  86000     5
## 261        5        1  90000     5
## 262        2        1  92000     7
## 263        2        1  95000     7
## 264        2        1  96000     6
## 265        2        1  98000     6
## 266        2        1 100000     6
## 267        2        1 100000     7
## 268        3        1 100400     7
## 269        3        1 101600     6
## 270        4        2 104000     6
## 271        2        1 105000     6
## 272        3        1 115000     5
## 273        3        1 126710     6
## 274       15        2 220000     6
str(mba1.df)
## 'data.frame':    193 obs. of  13 variables:
##  $ age     : int  23 24 24 24 24 25 25 27 27 28 ...
##  $ sex     : int  2 1 1 1 1 1 2 1 1 2 ...
##  $ gmat_tot: int  620 610 670 570 640 610 650 740 750 540 ...
##  $ gmat_qpc: int  77 90 99 56 82 89 88 99 99 75 ...
##  $ gmat_vpc: int  87 71 78 81 89 74 89 96 98 50 ...
##  $ gmat_tpc: int  87 87 95 75 91 87 92 99 99 65 ...
##  $ s_avg   : num  3.4 3.5 3.3 3.3 3.9 3.4 3.3 3.5 3.4 3.6 ...
##  $ f_avg   : num  3 4 3.25 2.67 3.75 3.5 3.75 3.5 3.5 4 ...
##  $ quarter : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ work_yrs: int  2 2 2 1 2 2 2 3 1 5 ...
##  $ frstlang: int  1 1 1 1 1 1 1 1 2 1 ...
##  $ salary  : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ satis   : int  7 6 6 7 6 5 6 6 5 5 ...
  1. Those who disclosed their salary
mba2.df <- mba.df[which(mba.df$salary!= 998 & mba.df$salary!= 999), ]
mba2.df
##     age sex gmat_tot gmat_qpc gmat_vpc gmat_tpc s_avg f_avg quarter
## 1    23   2      620       77       87       87  3.40  3.00       1
## 2    24   1      610       90       71       87  3.50  4.00       1
## 3    24   1      670       99       78       95  3.30  3.25       1
## 4    24   1      570       56       81       75  3.30  2.67       1
## 6    24   1      640       82       89       91  3.90  3.75       1
## 7    25   1      610       89       74       87  3.40  3.50       1
## 8    25   2      650       88       89       92  3.30  3.75       1
## 22   27   1      740       99       96       99  3.50  3.50       1
## 23   27   1      750       99       98       99  3.40  3.50       1
## 24   28   2      540       75       50       65  3.60  4.00       1
## 25   29   1      580       56       87       78  3.64  3.33       1
## 27   31   2      560       60       78       72  3.30  3.75       1
## 28   32   1      760       99       99       99  3.40  3.00       1
## 29   32   1      640       79       91       91  3.60  3.75       1
## 31   34   2      620       75       89       87  3.30  3.00       1
## 32   37   2      560       43       87       72  3.40  3.50       1
## 33   42   2      650       75       98       93  3.38  3.00       1
## 34   48   1      590       84       62       81  3.80  4.00       1
## 35   22   2      660       90       92       94  3.50  3.75       1
## 36   27   2      700       94       98       98  3.30  3.25       1
## 37   25   2      680       87       96       96  3.50  2.67       1
## 38   25   2      650       82       91       93  3.40  3.25       1
## 39   27   1      710       96       96       98  3.30  3.50       1
## 40   28   2      620       52       98       87  3.40  3.75       1
## 41   24   1      670       84       96       95  3.30  3.25       1
## 42   25   2      560       52       81       72  3.30  3.50       1
## 43   25   2      530       50       62       61  3.60  3.67       1
## 44   25   1      650       79       93       93  3.30  3.50       1
## 45   26   2      590       56       89       81  3.30  3.25       1
## 46   23   2      650       93       81       93  3.40  3.00       1
## 47   24   1      560       81       50       71  3.40  3.67       1
## 48   27   1      610       72       84       86  3.30  3.50       1
## 49   25   1      650       95       84       93  3.30  3.00       1
## 50   25   1      550       74       50       68  3.50  3.50       1
## 51   26   1      570       68       74       75  3.80  3.50       1
## 52   26   1      580       79       71       78  3.45  3.50       1
## 53   30   1      600       60       91       83  3.30  3.25       1
## 54   31   1      570       72       71       75  3.60  3.50       1
## 55   30   1      620       60       96       87  3.50  3.00       1
## 56   30   2      680       96       87       96  3.70  3.60       1
## 57   27   1      630       93       75       91  3.30  3.25       1
## 58   25   1      600       82       74       83  3.50  3.25       1
## 59   28   2      640       89       81       91  3.60  3.50       1
## 60   39   1      600       72       81       83  3.60  3.50       1
## 61   27   1      570       95       33       75  3.70  4.00       1
## 62   27   1      710       95       98       98  3.60  3.50       1
## 63   33   1      620       72       89       87  3.50  3.50       1
## 64   27   1      600       67       84       83  3.50  3.00       1
## 65   28   1      700       95       95       98  3.80  4.00       1
## 66   30   1      600       77       81       84  3.50  3.25       1
## 67   30   2      670       87       95       95  3.30  3.25       1
## 68   40   1      630       71       95       91  4.00  0.00       1
## 69   25   1      700       98       93       98  3.60  3.75       1
## 70   22   1      600       95       54       83  3.00  3.00       2
## 71   23   1      640       89       87       92  3.00  3.00       2
## 72   24   1      550       73       63       69  3.10  3.00       2
## 73   24   1      570       82       58       75  3.09  3.50       2
## 74   24   1      620       82       84       87  3.10  3.50       2
## 75   25   2      570       61       81       76  3.00  3.25       2
## 76   25   1      660       94       84       94  3.27  3.75       2
## 77   25   1      680       94       92       97  3.17  3.50       2
## 88   26   2      560       64       71       72  3.20  3.25       2
## 89   26   1      560       87       41       72  3.00  3.00       2
## 90   26   1      530       68       54       62  3.09  3.17       2
## 92   27   1      720       99       95       99  3.10  3.25       2
## 93   27   1      590       60       87       81  3.00  2.75       2
## 97   28   1      620       81       90       89  3.20  3.00       2
## 98   28   2      610       85       78       86  3.10  3.00       2
## 100  29   1      660       94       87       94  3.00  3.00       2
## 102  29   1      510       57       50       55  3.27  3.40       2
## 103  29   2      640       90       84       92  3.20  3.00       2
## 104  29   1      610       91       62       86  3.10  3.67       2
## 106  29   1      580       79       67       78  3.00  3.25       2
## 107  30   1      680       97       87       96  3.00  3.00       2
## 109  32   2      610       64       89       86  3.25  0.00       2
## 110  35   1      540       43       78       65  3.20  3.25       2
## 111  35   1      630       66       95       90  3.08  3.25       2
## 112  36   2      530       48       71       62  3.00  2.50       2
## 113  36   1      650       87       89       93  3.00  3.20       2
## 114  43   1      630       82       87       89  3.10  3.00       2
## 115  26   2      670       87       95       95  3.10  3.33       2
## 116  25   2      620       89       74       87  3.10  3.50       2
## 117  31   1      540       60       62       65  3.10  3.00       2
## 118  25   1      670       95       89       95  3.20  3.50       2
## 119  25   1      610       87       71       86  3.27  3.25       2
## 120  24   1      560       52       81       72  3.20  3.25       2
## 121  24   1      500       78       30       52  3.00  2.75       2
## 122  23   1      590       72       81       81  3.20  3.25       2
## 123  24   1      570       82       58       75  3.20  3.25       2
## 124  26   2      570       93       37       75  3.00  2.75       2
## 125  28   2      580       83       58       79  3.10  3.00       2
## 126  24   2      580       72       71       78  3.00  3.25       2
## 127  31   1      560       68       67       72  3.09  3.00       2
## 128  25   2      620       89       74       87  3.10  3.50       2
## 129  27   1      620       97       63       88  3.20  3.00       2
## 130  28   1      560       75       58       72  3.20  3.25       2
## 131  26   1      680       84       96       96  3.20  3.25       2
## 132  27   1      620       81       87       89  3.00  3.00       2
## 133  34   1      550       72       58       69  3.00  3.00       2
## 134  26   1      600       84       67       83  3.09  3.50       2
## 135  29   1      670       91       93       95  3.10  3.00       2
## 136  24   1      620       84       81       87  3.00  3.25       2
## 137  27   1      630       72       95       89  3.20  3.00       2
## 138  26   1      650       89       87       93  3.20  3.25       2
## 139  24   1      620       88       74       87  3.10  3.00       2
## 140  23   1      720       95       98       99  2.80  2.50       3
## 141  24   2      640       94       78       92  2.90  3.25       3
## 142  24   1      710       96       97       99  2.80  2.75       3
## 143  24   1      670       94       89       96  2.70  3.00       3
## 144  24   2      710       97       97       99  2.80  3.00       3
## 146  24   1      600       89       62       83  2.90  3.00       3
## 147  24   2      640       96       71       91  2.70  2.50       3
## 150  25   1      550       72       58       69  2.90  3.00       3
## 151  25   1      710       99       91       98  2.90  3.25       3
## 159  26   1      560       56       81       72  2.80  3.25       3
## 160  26   1      540       52       71       65  2.70  2.75       3
## 162  26   2      570       48       89       75  2.82  2.50       3
## 163  26   1      610       82       81       86  2.90  2.75       3
## 164  27   1      650       89       84       93  2.90  3.00       3
## 165  27   2      550       66       63       69  2.90  3.00       3
## 167  27   1      610       97       45       86  2.70  2.50       3
## 168  27   2      630       82       89       89  2.70  3.25       3
## 169  27   2      560       61       74       73  2.80  3.25       3
## 180  29   1      590       92       58       81  2.80  2.75       3
## 182  32   1      550       52       78       71  2.70  2.75       3
## 183  34   1      610       79       81       86  2.80  3.00       3
## 184  34   1      610       82       78       86  2.70  3.00       3
## 185  43   1      480       49       41       45  2.90  3.25       3
## 186  23   2      520       43       67       58  2.90  2.75       3
## 187  27   1      620       87       74       87  2.70  2.75       3
## 188  25   1      580       78       67       80  2.90  3.25       3
## 189  25   1      630       75       93       89  2.70  2.50       3
## 190  25   1      610       89       74       87  2.70  2.75       3
## 191  29   2      560       64       71       72  2.90  3.00       3
## 192  27   1      620       79       87       88  2.90  2.75       3
## 193  28   1      580       72       71       78  2.80  3.00       3
## 194  24   2      670       83       98       96  2.90  3.25       3
## 195  25   2      560       39       91       72  2.90  3.00       3
## 196  25   2      580       72       71       78  2.80  3.25       3
## 197  27   1      680       97       90       97  2.90  2.75       3
## 198  28   1      610       89       67       86  2.70  3.00       3
## 199  29   1      710       93       98       99  2.90  3.25       3
## 200  24   1      710       99       92       99  2.90  3.00       3
## 201  25   2      630       84       87       89  2.80  2.75       3
## 202  24   2      600       89       67       85  2.80  3.00       3
## 203  29   1      660       91       90       95  2.80  3.00       3
## 204  30   1      670       83       97       96  2.80  2.75       3
## 205  24   1      580       89       54       78  2.91  2.83       3
## 206  29   1      680       79       99       96  2.90  3.00       3
## 207  32   1      660       83       95       94  2.90  3.50       3
## 208  28   1      570       56       84       75  2.90  3.00       3
## 209  24   1      680       96       87       97  2.80  2.75       3
## 213  25   1      730       98       96       99  2.40  2.75       4
## 218  25   1      700       99       87       98  2.00  2.00       4
## 219  26   1      660       93       87       95  2.60  2.00       4
## 220  26   1      450       28       46       34  2.10  2.00       4
## 222  26   1      600       75       78       83  2.20  2.25       4
## 227  27   2      560       59       74       73  2.40  2.50       4
## 229  27   1      630       93       78       91  2.10  2.50       4
## 230  27   1      580       84       58       78  2.70  2.75       4
## 232  27   1      670       89       91       95  3.60  3.25       4
## 233  27   1      580       74       70       78  3.40  3.25       4
## 234  28   1      560       74       67       73  3.60  3.60       4
## 236  28   1      710       94       98       99  3.40  3.75       4
## 237  28   1      570       69       71        0  2.30  2.50       4
## 238  29   1      530       35       81       62  3.30  2.75       4
## 241  29   1      670       91       91       95  3.30  3.25       4
## 242  29   1      630       99       50       89  2.90  3.25       4
## 243  29   2      680       89       96       96  2.80  3.00       4
## 244  30   1      650       88       92       93  3.45  3.83       4
## 250  31   1      570       75       62       75  2.80  3.00       4
## 253  32   1      510       79       22       54  2.30  2.25       4
## 254  35   1      570       72       71       75  3.30  4.00       4
## 255  39   2      700       89       98       98  3.30  3.25       4
## 256  24   2      560       55       78       71  3.50  3.25       4
## 257  23   1      660       81       98       95  2.50  3.00       4
## 258  25   2      720       96       98       99  3.50  3.60       4
## 259  26   1      620       78       87       89  2.40  2.00       4
## 260  26   2      630       85       81       90  2.90  3.25       4
## 261  27   1      650       89       89       93  2.40  2.25       4
## 262  25   1      660       99       71       95  3.40  3.25       4
## 263  25   1      610       83       81       86  2.40  2.75       4
## 264  26   1      600       87       62       83  2.50  2.50       4
## 265  24   1      570       75       62       75  2.30  2.50       4
## 266  24   2      600       77       78       84  2.60  3.00       4
## 267  26   2      650       91       84       93  2.60  3.00       4
## 268  29   1      630       72       95       89  2.60  2.50       4
## 269  26   1      630       96       71       91  2.60  2.75       4
## 270  31   1      530       75       45       62  2.40  2.75       4
## 271  23   1      580       64       81       78  2.20  2.00       4
## 272  25   1      540       79       45       65  2.60  2.50       4
## 273  26   1      550       72       58       69  2.60  2.75       4
## 274  40   2      500       60       45       51  2.50  2.75       4
##     work_yrs frstlang salary satis
## 1          2        1      0     7
## 2          2        1      0     6
## 3          2        1      0     6
## 4          1        1      0     7
## 6          2        1      0     6
## 7          2        1      0     5
## 8          2        1      0     6
## 22         3        1      0     6
## 23         1        2      0     5
## 24         5        1      0     5
## 25         3        1      0     5
## 27        10        1      0     7
## 28         5        1      0     5
## 29         7        1      0     6
## 31         7        1      0     6
## 32         9        1      0     6
## 33        13        1      0     5
## 34        22        1      0     6
## 35         1        1  85000     5
## 36         2        1  85000     6
## 37         2        1  86000     5
## 38         3        1  88000     7
## 39         2        1  92000     6
## 40         5        1  93000     5
## 41         0        1  95000     4
## 42         1        1  95000     5
## 43         3        1  95000     3
## 44         1        1  96000     7
## 45         4        1  96000     5
## 46         2        1 100000     7
## 47         2        1 100000     6
## 48         6        1 100000     6
## 49         2        1 105000     7
## 50         3        1 105000     6
## 51         3        1 105000     6
## 52         2        1 105000     5
## 53         5        1 105000     6
## 54         6        1 105000     6
## 55         8        1 106000     7
## 56         6        1 106000     6
## 57         3        1 107500     5
## 58         3        1 108000     6
## 59         6        1 110000     5
## 60        16        1 112000     7
## 61         4        1 115000     5
## 62         1        1 115000     5
## 63        10        2 118000     7
## 64         3        1 120000     5
## 65         5        1 120000     5
## 66         5        1 120000     6
## 67         8        1 120000     6
## 68        15        1 146000     6
## 69         1        1 162000     5
## 70         1        1      0     5
## 71         2        1      0     7
## 72         0        2      0     5
## 73         2        1      0     6
## 74         1        1      0     5
## 75         3        1      0     4
## 76         2        1      0     5
## 77         2        1      0     6
## 88         3        1      0     6
## 89         3        1      0     6
## 90         4        2      0     5
## 92         5        1      0     5
## 93         3        1      0     6
## 97         4        1      0     6
## 98         5        1      0     6
## 100        1        1      0     6
## 102        5        1      0     5
## 103        3        1      0     5
## 104        7        1      0     5
## 106        4        1      0     6
## 107        4        1      0     5
## 109       11        1      0     7
## 110        8        1      0     5
## 111       12        1      0     5
## 112        7        1      0     5
## 113       18        1      0     6
## 114       16        1      0     5
## 115        1        1  82000     7
## 116        2        1  92000     5
## 117        8        1  93000     6
## 118        2        1  95000     6
## 119        3        1  95000     6
## 120        2        1  96000     7
## 121        2        1  96500     6
## 122        2        1  98000     6
## 123        2        1  98000     6
## 124        3        2  98000     5
## 125        5        2  99000     6
## 126        2        1 100000     5
## 127        4        1 100000     6
## 128        2        1 101000     5
## 129        3        1 103000     6
## 130        4        1 104000     5
## 131        3        1 105000     6
## 132        3        1 105000     5
## 133       16        1 105000     5
## 134        2        1 107000     5
## 135        6        1 112000     6
## 136        1        1 115000     6
## 137        4        1 115000     6
## 138        4        1 130000     7
## 139        2        1 145800     6
## 140        1        1      0     5
## 141        2        2      0     4
## 142        2        1      0     7
## 143        2        1      0     7
## 144        2        1      0     7
## 146        1        1      0     6
## 147        2        1      0     6
## 150        3        1      0     6
## 151        1        1      0     6
## 159        4        1      0     6
## 160        2        1      0     6
## 162        3        1      0     5
## 163        3        1      0     6
## 164        2        1      0     6
## 165        3        1      0     4
## 167        4        2      0     5
## 168        5        1      0     6
## 169        5        1      0     6
## 180        3        2      0     5
## 182        7        1      0     6
## 183       11        1      0     6
## 184       12        1      0     5
## 185       22        1      0     5
## 186        1        1  78256     5
## 187        3        1  88500     6
## 188        2        1  90000     7
## 189        2        1  90000     5
## 190        4        1  93000     6
## 191        5        1  95000     7
## 192        4        1  97000     7
## 193        3        1  97000     6
## 194        2        1  98000     7
## 195        2        1  98000     7
## 196        2        1  98000     6
## 197        2        2  98000     6
## 198        4        1  98000     7
## 199        7        1  98000     5
## 200        3        1 100000     6
## 201        2        1 100000     6
## 202        2        1 101000     6
## 203        8        1 101100     6
## 204        6        1 102500     5
## 205        2        1 105000     5
## 206        6        1 106000     6
## 207        2        2 107300     7
## 208        4        1 108000     6
## 209        2        1 112000     6
## 213        2        1      0     6
## 218        1        1      0     7
## 219        2        1      0     5
## 220        4        1      0     6
## 222        2        1      0     6
## 227        2        1      0     5
## 229        4        1      0     5
## 230        1        1      0     5
## 232        5        1      0     6
## 233        3        1      0     6
## 234        5        1      0     5
## 236        6        1      0     6
## 237        5        1      0     5
## 238        6        1      0     7
## 241        3        1      0     5
## 242        1        2      0     4
## 243        4        1      0     5
## 244        2        1      0     6
## 250        1        1      0     6
## 253        5        2      0     5
## 254        8        1      0     6
## 255        5        1      0     5
## 256        2        1  64000     7
## 257        2        1  77000     6
## 258        3        1  85000     6
## 259        2        1  85000     6
## 260        3        1  86000     5
## 261        5        1  90000     5
## 262        2        1  92000     7
## 263        2        1  95000     7
## 264        2        1  96000     6
## 265        2        1  98000     6
## 266        2        1 100000     6
## 267        2        1 100000     7
## 268        3        1 100400     7
## 269        3        1 101600     6
## 270        4        2 104000     6
## 271        2        1 105000     6
## 272        3        1 115000     5
## 273        3        1 126710     6
## 274       15        2 220000     6
str(mba2.df)
## 'data.frame':    193 obs. of  13 variables:
##  $ age     : int  23 24 24 24 24 25 25 27 27 28 ...
##  $ sex     : int  2 1 1 1 1 1 2 1 1 2 ...
##  $ gmat_tot: int  620 610 670 570 640 610 650 740 750 540 ...
##  $ gmat_qpc: int  77 90 99 56 82 89 88 99 99 75 ...
##  $ gmat_vpc: int  87 71 78 81 89 74 89 96 98 50 ...
##  $ gmat_tpc: int  87 87 95 75 91 87 92 99 99 65 ...
##  $ s_avg   : num  3.4 3.5 3.3 3.3 3.9 3.4 3.3 3.5 3.4 3.6 ...
##  $ f_avg   : num  3 4 3.25 2.67 3.75 3.5 3.75 3.5 3.5 4 ...
##  $ quarter : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ work_yrs: int  2 2 2 1 2 2 2 3 1 5 ...
##  $ frstlang: int  1 1 1 1 1 1 1 1 2 1 ...
##  $ salary  : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ satis   : int  7 6 6 7 6 5 6 6 5 5 ...
  1. placed and disclosed their salary and satisfaction
mba3.df <- mba.df[which(mba.df$salary!= 998 & mba.df$salary!= 999 & mba.df$satis!= 998 & mba.df$salary!= 0), ]
mba3.df
##     age sex gmat_tot gmat_qpc gmat_vpc gmat_tpc s_avg f_avg quarter
## 35   22   2      660       90       92       94  3.50  3.75       1
## 36   27   2      700       94       98       98  3.30  3.25       1
## 37   25   2      680       87       96       96  3.50  2.67       1
## 38   25   2      650       82       91       93  3.40  3.25       1
## 39   27   1      710       96       96       98  3.30  3.50       1
## 40   28   2      620       52       98       87  3.40  3.75       1
## 41   24   1      670       84       96       95  3.30  3.25       1
## 42   25   2      560       52       81       72  3.30  3.50       1
## 43   25   2      530       50       62       61  3.60  3.67       1
## 44   25   1      650       79       93       93  3.30  3.50       1
## 45   26   2      590       56       89       81  3.30  3.25       1
## 46   23   2      650       93       81       93  3.40  3.00       1
## 47   24   1      560       81       50       71  3.40  3.67       1
## 48   27   1      610       72       84       86  3.30  3.50       1
## 49   25   1      650       95       84       93  3.30  3.00       1
## 50   25   1      550       74       50       68  3.50  3.50       1
## 51   26   1      570       68       74       75  3.80  3.50       1
## 52   26   1      580       79       71       78  3.45  3.50       1
## 53   30   1      600       60       91       83  3.30  3.25       1
## 54   31   1      570       72       71       75  3.60  3.50       1
## 55   30   1      620       60       96       87  3.50  3.00       1
## 56   30   2      680       96       87       96  3.70  3.60       1
## 57   27   1      630       93       75       91  3.30  3.25       1
## 58   25   1      600       82       74       83  3.50  3.25       1
## 59   28   2      640       89       81       91  3.60  3.50       1
## 60   39   1      600       72       81       83  3.60  3.50       1
## 61   27   1      570       95       33       75  3.70  4.00       1
## 62   27   1      710       95       98       98  3.60  3.50       1
## 63   33   1      620       72       89       87  3.50  3.50       1
## 64   27   1      600       67       84       83  3.50  3.00       1
## 65   28   1      700       95       95       98  3.80  4.00       1
## 66   30   1      600       77       81       84  3.50  3.25       1
## 67   30   2      670       87       95       95  3.30  3.25       1
## 68   40   1      630       71       95       91  4.00  0.00       1
## 69   25   1      700       98       93       98  3.60  3.75       1
## 115  26   2      670       87       95       95  3.10  3.33       2
## 116  25   2      620       89       74       87  3.10  3.50       2
## 117  31   1      540       60       62       65  3.10  3.00       2
## 118  25   1      670       95       89       95  3.20  3.50       2
## 119  25   1      610       87       71       86  3.27  3.25       2
## 120  24   1      560       52       81       72  3.20  3.25       2
## 121  24   1      500       78       30       52  3.00  2.75       2
## 122  23   1      590       72       81       81  3.20  3.25       2
## 123  24   1      570       82       58       75  3.20  3.25       2
## 124  26   2      570       93       37       75  3.00  2.75       2
## 125  28   2      580       83       58       79  3.10  3.00       2
## 126  24   2      580       72       71       78  3.00  3.25       2
## 127  31   1      560       68       67       72  3.09  3.00       2
## 128  25   2      620       89       74       87  3.10  3.50       2
## 129  27   1      620       97       63       88  3.20  3.00       2
## 130  28   1      560       75       58       72  3.20  3.25       2
## 131  26   1      680       84       96       96  3.20  3.25       2
## 132  27   1      620       81       87       89  3.00  3.00       2
## 133  34   1      550       72       58       69  3.00  3.00       2
## 134  26   1      600       84       67       83  3.09  3.50       2
## 135  29   1      670       91       93       95  3.10  3.00       2
## 136  24   1      620       84       81       87  3.00  3.25       2
## 137  27   1      630       72       95       89  3.20  3.00       2
## 138  26   1      650       89       87       93  3.20  3.25       2
## 139  24   1      620       88       74       87  3.10  3.00       2
## 186  23   2      520       43       67       58  2.90  2.75       3
## 187  27   1      620       87       74       87  2.70  2.75       3
## 188  25   1      580       78       67       80  2.90  3.25       3
## 189  25   1      630       75       93       89  2.70  2.50       3
## 190  25   1      610       89       74       87  2.70  2.75       3
## 191  29   2      560       64       71       72  2.90  3.00       3
## 192  27   1      620       79       87       88  2.90  2.75       3
## 193  28   1      580       72       71       78  2.80  3.00       3
## 194  24   2      670       83       98       96  2.90  3.25       3
## 195  25   2      560       39       91       72  2.90  3.00       3
## 196  25   2      580       72       71       78  2.80  3.25       3
## 197  27   1      680       97       90       97  2.90  2.75       3
## 198  28   1      610       89       67       86  2.70  3.00       3
## 199  29   1      710       93       98       99  2.90  3.25       3
## 200  24   1      710       99       92       99  2.90  3.00       3
## 201  25   2      630       84       87       89  2.80  2.75       3
## 202  24   2      600       89       67       85  2.80  3.00       3
## 203  29   1      660       91       90       95  2.80  3.00       3
## 204  30   1      670       83       97       96  2.80  2.75       3
## 205  24   1      580       89       54       78  2.91  2.83       3
## 206  29   1      680       79       99       96  2.90  3.00       3
## 207  32   1      660       83       95       94  2.90  3.50       3
## 208  28   1      570       56       84       75  2.90  3.00       3
## 209  24   1      680       96       87       97  2.80  2.75       3
## 256  24   2      560       55       78       71  3.50  3.25       4
## 257  23   1      660       81       98       95  2.50  3.00       4
## 258  25   2      720       96       98       99  3.50  3.60       4
## 259  26   1      620       78       87       89  2.40  2.00       4
## 260  26   2      630       85       81       90  2.90  3.25       4
## 261  27   1      650       89       89       93  2.40  2.25       4
## 262  25   1      660       99       71       95  3.40  3.25       4
## 263  25   1      610       83       81       86  2.40  2.75       4
## 264  26   1      600       87       62       83  2.50  2.50       4
## 265  24   1      570       75       62       75  2.30  2.50       4
## 266  24   2      600       77       78       84  2.60  3.00       4
## 267  26   2      650       91       84       93  2.60  3.00       4
## 268  29   1      630       72       95       89  2.60  2.50       4
## 269  26   1      630       96       71       91  2.60  2.75       4
## 270  31   1      530       75       45       62  2.40  2.75       4
## 271  23   1      580       64       81       78  2.20  2.00       4
## 272  25   1      540       79       45       65  2.60  2.50       4
## 273  26   1      550       72       58       69  2.60  2.75       4
## 274  40   2      500       60       45       51  2.50  2.75       4
##     work_yrs frstlang salary satis
## 35         1        1  85000     5
## 36         2        1  85000     6
## 37         2        1  86000     5
## 38         3        1  88000     7
## 39         2        1  92000     6
## 40         5        1  93000     5
## 41         0        1  95000     4
## 42         1        1  95000     5
## 43         3        1  95000     3
## 44         1        1  96000     7
## 45         4        1  96000     5
## 46         2        1 100000     7
## 47         2        1 100000     6
## 48         6        1 100000     6
## 49         2        1 105000     7
## 50         3        1 105000     6
## 51         3        1 105000     6
## 52         2        1 105000     5
## 53         5        1 105000     6
## 54         6        1 105000     6
## 55         8        1 106000     7
## 56         6        1 106000     6
## 57         3        1 107500     5
## 58         3        1 108000     6
## 59         6        1 110000     5
## 60        16        1 112000     7
## 61         4        1 115000     5
## 62         1        1 115000     5
## 63        10        2 118000     7
## 64         3        1 120000     5
## 65         5        1 120000     5
## 66         5        1 120000     6
## 67         8        1 120000     6
## 68        15        1 146000     6
## 69         1        1 162000     5
## 115        1        1  82000     7
## 116        2        1  92000     5
## 117        8        1  93000     6
## 118        2        1  95000     6
## 119        3        1  95000     6
## 120        2        1  96000     7
## 121        2        1  96500     6
## 122        2        1  98000     6
## 123        2        1  98000     6
## 124        3        2  98000     5
## 125        5        2  99000     6
## 126        2        1 100000     5
## 127        4        1 100000     6
## 128        2        1 101000     5
## 129        3        1 103000     6
## 130        4        1 104000     5
## 131        3        1 105000     6
## 132        3        1 105000     5
## 133       16        1 105000     5
## 134        2        1 107000     5
## 135        6        1 112000     6
## 136        1        1 115000     6
## 137        4        1 115000     6
## 138        4        1 130000     7
## 139        2        1 145800     6
## 186        1        1  78256     5
## 187        3        1  88500     6
## 188        2        1  90000     7
## 189        2        1  90000     5
## 190        4        1  93000     6
## 191        5        1  95000     7
## 192        4        1  97000     7
## 193        3        1  97000     6
## 194        2        1  98000     7
## 195        2        1  98000     7
## 196        2        1  98000     6
## 197        2        2  98000     6
## 198        4        1  98000     7
## 199        7        1  98000     5
## 200        3        1 100000     6
## 201        2        1 100000     6
## 202        2        1 101000     6
## 203        8        1 101100     6
## 204        6        1 102500     5
## 205        2        1 105000     5
## 206        6        1 106000     6
## 207        2        2 107300     7
## 208        4        1 108000     6
## 209        2        1 112000     6
## 256        2        1  64000     7
## 257        2        1  77000     6
## 258        3        1  85000     6
## 259        2        1  85000     6
## 260        3        1  86000     5
## 261        5        1  90000     5
## 262        2        1  92000     7
## 263        2        1  95000     7
## 264        2        1  96000     6
## 265        2        1  98000     6
## 266        2        1 100000     6
## 267        2        1 100000     7
## 268        3        1 100400     7
## 269        3        1 101600     6
## 270        4        2 104000     6
## 271        2        1 105000     6
## 272        3        1 115000     5
## 273        3        1 126710     6
## 274       15        2 220000     6
str(mba3.df)
## 'data.frame':    103 obs. of  13 variables:
##  $ age     : int  22 27 25 25 27 28 24 25 25 25 ...
##  $ sex     : int  2 2 2 2 1 2 1 2 2 1 ...
##  $ gmat_tot: int  660 700 680 650 710 620 670 560 530 650 ...
##  $ gmat_qpc: int  90 94 87 82 96 52 84 52 50 79 ...
##  $ gmat_vpc: int  92 98 96 91 96 98 96 81 62 93 ...
##  $ gmat_tpc: int  94 98 96 93 98 87 95 72 61 93 ...
##  $ s_avg   : num  3.5 3.3 3.5 3.4 3.3 3.4 3.3 3.3 3.6 3.3 ...
##  $ f_avg   : num  3.75 3.25 2.67 3.25 3.5 3.75 3.25 3.5 3.67 3.5 ...
##  $ quarter : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ work_yrs: int  1 2 2 3 2 5 0 1 3 1 ...
##  $ frstlang: int  1 1 1 1 1 1 1 1 1 1 ...
##  $ salary  : int  85000 85000 86000 88000 92000 93000 95000 95000 95000 96000 ...
##  $ satis   : int  5 6 5 7 6 5 4 5 3 7 ...
  1. disclosed and not placed
mba4.df <- mba.df[which(mba.df$salary!=998 & mba.df$salary!=999 & mba.df$salary==0 & mba.df$satis!= 998), ]
mba4.df
##     age sex gmat_tot gmat_qpc gmat_vpc gmat_tpc s_avg f_avg quarter
## 1    23   2      620       77       87       87  3.40  3.00       1
## 2    24   1      610       90       71       87  3.50  4.00       1
## 3    24   1      670       99       78       95  3.30  3.25       1
## 4    24   1      570       56       81       75  3.30  2.67       1
## 6    24   1      640       82       89       91  3.90  3.75       1
## 7    25   1      610       89       74       87  3.40  3.50       1
## 8    25   2      650       88       89       92  3.30  3.75       1
## 22   27   1      740       99       96       99  3.50  3.50       1
## 23   27   1      750       99       98       99  3.40  3.50       1
## 24   28   2      540       75       50       65  3.60  4.00       1
## 25   29   1      580       56       87       78  3.64  3.33       1
## 27   31   2      560       60       78       72  3.30  3.75       1
## 28   32   1      760       99       99       99  3.40  3.00       1
## 29   32   1      640       79       91       91  3.60  3.75       1
## 31   34   2      620       75       89       87  3.30  3.00       1
## 32   37   2      560       43       87       72  3.40  3.50       1
## 33   42   2      650       75       98       93  3.38  3.00       1
## 34   48   1      590       84       62       81  3.80  4.00       1
## 70   22   1      600       95       54       83  3.00  3.00       2
## 71   23   1      640       89       87       92  3.00  3.00       2
## 72   24   1      550       73       63       69  3.10  3.00       2
## 73   24   1      570       82       58       75  3.09  3.50       2
## 74   24   1      620       82       84       87  3.10  3.50       2
## 75   25   2      570       61       81       76  3.00  3.25       2
## 76   25   1      660       94       84       94  3.27  3.75       2
## 77   25   1      680       94       92       97  3.17  3.50       2
## 88   26   2      560       64       71       72  3.20  3.25       2
## 89   26   1      560       87       41       72  3.00  3.00       2
## 90   26   1      530       68       54       62  3.09  3.17       2
## 92   27   1      720       99       95       99  3.10  3.25       2
## 93   27   1      590       60       87       81  3.00  2.75       2
## 97   28   1      620       81       90       89  3.20  3.00       2
## 98   28   2      610       85       78       86  3.10  3.00       2
## 100  29   1      660       94       87       94  3.00  3.00       2
## 102  29   1      510       57       50       55  3.27  3.40       2
## 103  29   2      640       90       84       92  3.20  3.00       2
## 104  29   1      610       91       62       86  3.10  3.67       2
## 106  29   1      580       79       67       78  3.00  3.25       2
## 107  30   1      680       97       87       96  3.00  3.00       2
## 109  32   2      610       64       89       86  3.25  0.00       2
## 110  35   1      540       43       78       65  3.20  3.25       2
## 111  35   1      630       66       95       90  3.08  3.25       2
## 112  36   2      530       48       71       62  3.00  2.50       2
## 113  36   1      650       87       89       93  3.00  3.20       2
## 114  43   1      630       82       87       89  3.10  3.00       2
## 140  23   1      720       95       98       99  2.80  2.50       3
## 141  24   2      640       94       78       92  2.90  3.25       3
## 142  24   1      710       96       97       99  2.80  2.75       3
## 143  24   1      670       94       89       96  2.70  3.00       3
## 144  24   2      710       97       97       99  2.80  3.00       3
## 146  24   1      600       89       62       83  2.90  3.00       3
## 147  24   2      640       96       71       91  2.70  2.50       3
## 150  25   1      550       72       58       69  2.90  3.00       3
## 151  25   1      710       99       91       98  2.90  3.25       3
## 159  26   1      560       56       81       72  2.80  3.25       3
## 160  26   1      540       52       71       65  2.70  2.75       3
## 162  26   2      570       48       89       75  2.82  2.50       3
## 163  26   1      610       82       81       86  2.90  2.75       3
## 164  27   1      650       89       84       93  2.90  3.00       3
## 165  27   2      550       66       63       69  2.90  3.00       3
## 167  27   1      610       97       45       86  2.70  2.50       3
## 168  27   2      630       82       89       89  2.70  3.25       3
## 169  27   2      560       61       74       73  2.80  3.25       3
## 180  29   1      590       92       58       81  2.80  2.75       3
## 182  32   1      550       52       78       71  2.70  2.75       3
## 183  34   1      610       79       81       86  2.80  3.00       3
## 184  34   1      610       82       78       86  2.70  3.00       3
## 185  43   1      480       49       41       45  2.90  3.25       3
## 213  25   1      730       98       96       99  2.40  2.75       4
## 218  25   1      700       99       87       98  2.00  2.00       4
## 219  26   1      660       93       87       95  2.60  2.00       4
## 220  26   1      450       28       46       34  2.10  2.00       4
## 222  26   1      600       75       78       83  2.20  2.25       4
## 227  27   2      560       59       74       73  2.40  2.50       4
## 229  27   1      630       93       78       91  2.10  2.50       4
## 230  27   1      580       84       58       78  2.70  2.75       4
## 232  27   1      670       89       91       95  3.60  3.25       4
## 233  27   1      580       74       70       78  3.40  3.25       4
## 234  28   1      560       74       67       73  3.60  3.60       4
## 236  28   1      710       94       98       99  3.40  3.75       4
## 237  28   1      570       69       71        0  2.30  2.50       4
## 238  29   1      530       35       81       62  3.30  2.75       4
## 241  29   1      670       91       91       95  3.30  3.25       4
## 242  29   1      630       99       50       89  2.90  3.25       4
## 243  29   2      680       89       96       96  2.80  3.00       4
## 244  30   1      650       88       92       93  3.45  3.83       4
## 250  31   1      570       75       62       75  2.80  3.00       4
## 253  32   1      510       79       22       54  2.30  2.25       4
## 254  35   1      570       72       71       75  3.30  4.00       4
## 255  39   2      700       89       98       98  3.30  3.25       4
##     work_yrs frstlang salary satis
## 1          2        1      0     7
## 2          2        1      0     6
## 3          2        1      0     6
## 4          1        1      0     7
## 6          2        1      0     6
## 7          2        1      0     5
## 8          2        1      0     6
## 22         3        1      0     6
## 23         1        2      0     5
## 24         5        1      0     5
## 25         3        1      0     5
## 27        10        1      0     7
## 28         5        1      0     5
## 29         7        1      0     6
## 31         7        1      0     6
## 32         9        1      0     6
## 33        13        1      0     5
## 34        22        1      0     6
## 70         1        1      0     5
## 71         2        1      0     7
## 72         0        2      0     5
## 73         2        1      0     6
## 74         1        1      0     5
## 75         3        1      0     4
## 76         2        1      0     5
## 77         2        1      0     6
## 88         3        1      0     6
## 89         3        1      0     6
## 90         4        2      0     5
## 92         5        1      0     5
## 93         3        1      0     6
## 97         4        1      0     6
## 98         5        1      0     6
## 100        1        1      0     6
## 102        5        1      0     5
## 103        3        1      0     5
## 104        7        1      0     5
## 106        4        1      0     6
## 107        4        1      0     5
## 109       11        1      0     7
## 110        8        1      0     5
## 111       12        1      0     5
## 112        7        1      0     5
## 113       18        1      0     6
## 114       16        1      0     5
## 140        1        1      0     5
## 141        2        2      0     4
## 142        2        1      0     7
## 143        2        1      0     7
## 144        2        1      0     7
## 146        1        1      0     6
## 147        2        1      0     6
## 150        3        1      0     6
## 151        1        1      0     6
## 159        4        1      0     6
## 160        2        1      0     6
## 162        3        1      0     5
## 163        3        1      0     6
## 164        2        1      0     6
## 165        3        1      0     4
## 167        4        2      0     5
## 168        5        1      0     6
## 169        5        1      0     6
## 180        3        2      0     5
## 182        7        1      0     6
## 183       11        1      0     6
## 184       12        1      0     5
## 185       22        1      0     5
## 213        2        1      0     6
## 218        1        1      0     7
## 219        2        1      0     5
## 220        4        1      0     6
## 222        2        1      0     6
## 227        2        1      0     5
## 229        4        1      0     5
## 230        1        1      0     5
## 232        5        1      0     6
## 233        3        1      0     6
## 234        5        1      0     5
## 236        6        1      0     6
## 237        5        1      0     5
## 238        6        1      0     7
## 241        3        1      0     5
## 242        1        2      0     4
## 243        4        1      0     5
## 244        2        1      0     6
## 250        1        1      0     6
## 253        5        2      0     5
## 254        8        1      0     6
## 255        5        1      0     5
str(mba4.df)
## 'data.frame':    90 obs. of  13 variables:
##  $ age     : int  23 24 24 24 24 25 25 27 27 28 ...
##  $ sex     : int  2 1 1 1 1 1 2 1 1 2 ...
##  $ gmat_tot: int  620 610 670 570 640 610 650 740 750 540 ...
##  $ gmat_qpc: int  77 90 99 56 82 89 88 99 99 75 ...
##  $ gmat_vpc: int  87 71 78 81 89 74 89 96 98 50 ...
##  $ gmat_tpc: int  87 87 95 75 91 87 92 99 99 65 ...
##  $ s_avg   : num  3.4 3.5 3.3 3.3 3.9 3.4 3.3 3.5 3.4 3.6 ...
##  $ f_avg   : num  3 4 3.25 2.67 3.75 3.5 3.75 3.5 3.5 4 ...
##  $ quarter : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ work_yrs: int  2 2 2 1 2 2 2 3 1 5 ...
##  $ frstlang: int  1 1 1 1 1 1 1 1 2 1 ...
##  $ salary  : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ satis   : int  7 6 6 7 6 5 6 6 5 5 ...
library(psych)
## Warning: package 'psych' was built under R version 3.3.3
describe(mba1.df)
##          vars   n     mean       sd   median  trimmed      mad min    max
## age         1 193    27.59     4.22    27.00    26.86     2.97  22     48
## sex         2 193     1.28     0.45     1.00     1.23     0.00   1      2
## gmat_tot    3 193   615.23    56.54   610.00   614.19    59.30 450    760
## gmat_qpc    4 193    79.35    15.15    82.00    80.92    14.83  28     99
## gmat_vpc    5 193    78.13    16.10    81.00    79.87    14.83  22     99
## gmat_tpc    6 193    83.48    13.53    87.00    85.08    11.86   0     99
## s_avg       7 193     3.06     0.38     3.09     3.08     0.43   2      4
## f_avg       8 193     3.08     0.52     3.00     3.11     0.37   0      4
## quarter     9 193     2.39     1.10     2.00     2.37     1.48   1      4
## work_yrs   10 193     4.10     3.69     3.00     3.37     1.48   0     22
## frstlang   11 193     1.08     0.27     1.00     1.00     0.00   1      2
## salary     12 193 54985.32 53152.39 85000.00 52726.81 51891.00   0 220000
## satis      13 193     5.76     0.77     6.00     5.75     1.48   3      7
##           range  skew kurtosis      se
## age          26  1.93     4.55    0.30
## sex           1  0.97    -1.06    0.03
## gmat_tot    310  0.08    -0.31    4.07
## gmat_qpc     71 -0.88     0.23    1.09
## gmat_vpc     77 -0.90     0.36    1.16
## gmat_tpc     99 -1.87     7.03    0.97
## s_avg         2 -0.27    -0.15    0.03
## f_avg         4 -2.17    11.03    0.04
## quarter       3  0.13    -1.32    0.08
## work_yrs     22  2.47     7.02    0.27
## frstlang      1  3.13     7.84    0.02
## salary   220000  0.10    -1.45 3825.99
## satis         4 -0.17    -0.06    0.06

mean of all variables

1.age 2.gmat total 3.gmat quants 4.gmat verbal 5.gmat percentile 6.summer average 7.fall average

mean(mba.df$age)
## [1] 27.35766
mean(mba.df$gmat_tot)
## [1] 619.4526
mean(mba.df$gmat_qpc)
## [1] 80.64234
mean(mba.df$gmat_vpc)
## [1] 78.32117
mean(mba.df$gmat_tpc)
## [1] 84.19708
mean(mba.df$s_avg)
## [1] 3.025401
mean(mba.df$f_avg)
## [1] 3.061533

Mean, median and sd of salary for those information available

mean(mba1.df$salary)
## [1] 54985.32
median(mba1.df$salary)
## [1] 85000
sd(mba1.df$salary)
## [1] 53152.39
max(mba1.df$salary)
## [1] 220000
min(mba1.df$salary)
## [1] 0

Satisfaction

mean(mba1.df$satis)
## [1] 5.761658
max(mba1.df$satis)
## [1] 7
min(mba1.df$satis)
## [1] 3

BOX Plot for various variable

boxplot(mba.df$age)

hist(mba.df$sex, main = "Sex")

par(mfrow = c(2,2))
boxplot(mba.df$gmat_tot, main="Total GMAT score")
boxplot(mba.df$gmat_qpc, main="Quantitative GMAT percentile")
boxplot(mba.df$gmat_vpc, main="Verbal GMAT percentile")
boxplot(mba.df$gmat_tpc, main="Overall GMAT percentile")

par(mfrow = c(1,2))
boxplot(mba.df$s_avg, main="Spring MBA average")
boxplot(mba.df$f_avg, main="Fall MBA average")

par(mfrow = c(1,2))
boxplot(mba1.df$salary, main = "Salary")
barplot(mba1.df$salary)

par(mfrow = c(1,2))
boxplot(mba1.df$satis, main="Degree of satisfaction")
barplot(mba1.df$satis, main="Degree of satisfaction")

Scatterplots between the variables

plot(mba1.df$salary, mba1.df$age, main="Salary vs Age")

plot(mba1.df$salary, mba1.df$gmat_tot, main="Salary vs Total GMAT score")

plot(mba1.df$salary, mba1.df$gmat_qpc, main="Salary vs Quantitative GMAT percentile")

plot(mba1.df$salary, mba1.df$gmat_vpc, main="Salary vs Verbal GMAT percentile")

plot(mba1.df$salary, mba1.df$gmat_tpc, main="Salary vs Overall GMAT percentile")

plot(mba1.df$salary, mba1.df$s_avg, main="Salary vs Spring MBA average")

plot(mba1.df$salary, mba1.df$f_avg, main="Salary vs Fall MBA average")

plot(mba1.df$salary, mba1.df$quarter, main="Salary vs Quartile ranking")

plot(mba1.df$salary, mba1.df$satis, main="Salary vs Degree of satisfaction")

Correlation plot of the variables

library(corrplot)    
## Warning: package 'corrplot' was built under R version 3.3.3
## corrplot 0.84 loaded
corrplot(corr=cor(mba1.df[ , c(1:13)], use="complete.obs"), 
         method ="ellipse")

Corrgram of all the variables

library(corrgram)
## Warning: package 'corrgram' was built under R version 3.3.3
corrgram(mba1.df, order=TRUE,
         main="Corrgram of all the Variables",
         lower.panel=panel.shade, upper.panel=panel.pie,
         diag.panel=panel.minmax, text.panel=panel.txt) 

## Corelation test

x <- mba1.df[,c("age", "gmat_tot","gmat_qpc","gmat_vpc","gmat_tpc","s_avg", "f_avg","work_yrs")]
y <- mba1.df[,c("salary", "satis")]
cor(x,y)
##                 salary        satis
## age      -1.301987e-01 -0.073500580
## gmat_tot -5.685962e-05  0.079819458
## gmat_qpc  2.839164e-02 -0.020006117
## gmat_vpc  3.389965e-03  0.195134711
## gmat_tpc  6.094464e-02  0.132884339
## s_avg     9.632412e-02 -0.046399534
## f_avg     8.846655e-03 -0.114704819
## work_yrs -5.326685e-02 -0.007722658

Salary and gender

mytable <- xtabs(~ salary+sex,data= mba3.df)
mytable
##         sex
## salary    1  2
##   64000   0  1
##   77000   1  0
##   78256   0  1
##   82000   0  1
##   85000   1  3
##   86000   0  2
##   88000   0  1
##   88500   1  0
##   90000   3  0
##   92000   2  1
##   93000   2  1
##   95000   4  3
##   96000   3  1
##   96500   1  0
##   97000   2  0
##   98000   6  4
##   99000   0  1
##   100000  4  5
##   100400  1  0
##   101000  0  2
##   101100  1  0
##   101600  1  0
##   102500  1  0
##   103000  1  0
##   104000  2  0
##   105000 11  0
##   106000  2  1
##   107000  1  0
##   107300  1  0
##   107500  1  0
##   108000  2  0
##   110000  0  1
##   112000  3  0
##   115000  5  0
##   118000  1  0
##   120000  3  1
##   126710  1  0
##   130000  1  0
##   145800  1  0
##   146000  1  0
##   162000  1  0
##   220000  0  1
malesalary <- xtabs(~ salary+sex, data = mba3.df, sex==1)
femalesalary <- xtabs(~ salary+sex, data = mba3.df, sex==2)
margin.table(mytable,2)
## sex
##  1  2 
## 72 31
aggregate(mba3.df$salary, by=list(sex = mba3.df$sex), mean)
##   sex         x
## 1   1 104970.97
## 2   2  98524.39
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 52.681, df = 41, p-value = 0.1045

p > 0.01 suggest that their is no relationship between salary and gender.

salary and first language

mytable <- xtabs(~ salary+frstlang,data= mba3.df)
mytable
##         frstlang
## salary    1  2
##   64000   1  0
##   77000   1  0
##   78256   1  0
##   82000   1  0
##   85000   4  0
##   86000   2  0
##   88000   1  0
##   88500   1  0
##   90000   3  0
##   92000   3  0
##   93000   3  0
##   95000   7  0
##   96000   4  0
##   96500   1  0
##   97000   2  0
##   98000   8  2
##   99000   0  1
##   100000  9  0
##   100400  1  0
##   101000  2  0
##   101100  1  0
##   101600  1  0
##   102500  1  0
##   103000  1  0
##   104000  1  1
##   105000 11  0
##   106000  3  0
##   107000  1  0
##   107300  0  1
##   107500  1  0
##   108000  2  0
##   110000  1  0
##   112000  3  0
##   115000  5  0
##   118000  0  1
##   120000  4  0
##   126710  1  0
##   130000  1  0
##   145800  1  0
##   146000  1  0
##   162000  1  0
##   220000  0  1
aggregate(mba3.df$salary, by=list(language = mba3.df$frstlang), mean)
##   language        x
## 1        1 101748.6
## 2        2 120614.3
margin.table(mytable,2)
## frstlang
##  1  2 
## 96  7
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 69.847, df = 41, p-value = 0.003296

p < 0.05 suggest that is some relationship between salary and first language

salary and prior work experiance

mytable <- xtabs(~ salary+work_yrs,data= mba3.df)
mytable
##         work_yrs
## salary   0 1 2 3 4 5 6 7 8 10 15 16
##   64000  0 0 1 0 0 0 0 0 0  0  0  0
##   77000  0 0 1 0 0 0 0 0 0  0  0  0
##   78256  0 1 0 0 0 0 0 0 0  0  0  0
##   82000  0 1 0 0 0 0 0 0 0  0  0  0
##   85000  0 1 2 1 0 0 0 0 0  0  0  0
##   86000  0 0 1 1 0 0 0 0 0  0  0  0
##   88000  0 0 0 1 0 0 0 0 0  0  0  0
##   88500  0 0 0 1 0 0 0 0 0  0  0  0
##   90000  0 0 2 0 0 1 0 0 0  0  0  0
##   92000  0 0 3 0 0 0 0 0 0  0  0  0
##   93000  0 0 0 0 1 1 0 0 1  0  0  0
##   95000  1 1 2 2 0 1 0 0 0  0  0  0
##   96000  0 1 2 0 1 0 0 0 0  0  0  0
##   96500  0 0 1 0 0 0 0 0 0  0  0  0
##   97000  0 0 0 1 1 0 0 0 0  0  0  0
##   98000  0 0 7 1 1 0 0 1 0  0  0  0
##   99000  0 0 0 0 0 1 0 0 0  0  0  0
##   100000 0 0 6 1 1 0 1 0 0  0  0  0
##   100400 0 0 0 1 0 0 0 0 0  0  0  0
##   101000 0 0 2 0 0 0 0 0 0  0  0  0
##   101100 0 0 0 0 0 0 0 0 1  0  0  0
##   101600 0 0 0 1 0 0 0 0 0  0  0  0
##   102500 0 0 0 0 0 0 1 0 0  0  0  0
##   103000 0 0 0 1 0 0 0 0 0  0  0  0
##   104000 0 0 0 0 2 0 0 0 0  0  0  0
##   105000 0 0 4 4 0 1 1 0 0  0  0  1
##   106000 0 0 0 0 0 0 2 0 1  0  0  0
##   107000 0 0 1 0 0 0 0 0 0  0  0  0
##   107300 0 0 1 0 0 0 0 0 0  0  0  0
##   107500 0 0 0 1 0 0 0 0 0  0  0  0
##   108000 0 0 0 1 1 0 0 0 0  0  0  0
##   110000 0 0 0 0 0 0 1 0 0  0  0  0
##   112000 0 0 1 0 0 0 1 0 0  0  0  1
##   115000 0 2 0 1 2 0 0 0 0  0  0  0
##   118000 0 0 0 0 0 0 0 0 0  1  0  0
##   120000 0 0 0 1 0 2 0 0 1  0  0  0
##   126710 0 0 0 1 0 0 0 0 0  0  0  0
##   130000 0 0 0 0 1 0 0 0 0  0  0  0
##   145800 0 0 1 0 0 0 0 0 0  0  0  0
##   146000 0 0 0 0 0 0 0 0 0  0  1  0
##   162000 0 1 0 0 0 0 0 0 0  0  0  0
##   220000 0 0 0 0 0 0 0 0 0  0  1  0
margin.table(mytable,2)
## work_yrs
##  0  1  2  3  4  5  6  7  8 10 15 16 
##  1  8 38 21 11  7  7  1  4  1  2  2
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 535.23, df = 451, p-value = 0.003809

p< 0.05 suggest that is some relationship between salary and prior work experiance

salary and gmat total

mytable <- xtabs(~ salary+gmat_tot,data= mba3.df)
mytable
##         gmat_tot
## salary   500 520 530 540 550 560 570 580 590 600 610 620 630 640 650 660
##   64000    0   0   0   0   0   1   0   0   0   0   0   0   0   0   0   0
##   77000    0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   1
##   78256    0   1   0   0   0   0   0   0   0   0   0   0   0   0   0   0
##   82000    0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
##   85000    0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   1
##   86000    0   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0
##   88000    0   0   0   0   0   0   0   0   0   0   0   0   0   0   1   0
##   88500    0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   0
##   90000    0   0   0   0   0   0   0   1   0   0   0   0   1   0   1   0
##   92000    0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   1
##   93000    0   0   0   1   0   0   0   0   0   0   1   1   0   0   0   0
##   95000    0   0   1   0   0   2   0   0   0   0   2   0   0   0   0   0
##   96000    0   0   0   0   0   1   0   0   1   1   0   0   0   0   1   0
##   96500    1   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
##   97000    0   0   0   0   0   0   0   1   0   0   0   1   0   0   0   0
##   98000    0   0   0   0   0   1   3   1   1   0   1   0   0   0   0   0
##   99000    0   0   0   0   0   0   0   1   0   0   0   0   0   0   0   0
##   100000   0   0   0   0   0   2   0   1   0   1   1   0   1   0   2   0
##   100400   0   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0
##   101000   0   0   0   0   0   0   0   0   0   1   0   1   0   0   0   0
##   101100   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   1
##   101600   0   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0
##   102500   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
##   103000   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   0
##   104000   0   0   1   0   0   1   0   0   0   0   0   0   0   0   0   0
##   105000   0   0   0   0   2   0   2   3   0   1   0   1   0   0   1   0
##   106000   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   0
##   107000   0   0   0   0   0   0   0   0   0   1   0   0   0   0   0   0
##   107300   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   1
##   107500   0   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0
##   108000   0   0   0   0   0   0   1   0   0   1   0   0   0   0   0   0
##   110000   0   0   0   0   0   0   0   0   0   0   0   0   0   1   0   0
##   112000   0   0   0   0   0   0   0   0   0   1   0   0   0   0   0   0
##   115000   0   0   0   1   0   0   1   0   0   0   0   1   1   0   0   0
##   118000   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   0
##   120000   0   0   0   0   0   0   0   0   0   2   0   0   0   0   0   0
##   126710   0   0   0   0   1   0   0   0   0   0   0   0   0   0   0   0
##   130000   0   0   0   0   0   0   0   0   0   0   0   0   0   0   1   0
##   145800   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0   0
##   146000   0   0   0   0   0   0   0   0   0   0   0   0   1   0   0   0
##   162000   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
##   220000   1   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
##         gmat_tot
## salary   670 680 700 710 720
##   64000    0   0   0   0   0
##   77000    0   0   0   0   0
##   78256    0   0   0   0   0
##   82000    1   0   0   0   0
##   85000    0   0   1   0   1
##   86000    0   1   0   0   0
##   88000    0   0   0   0   0
##   88500    0   0   0   0   0
##   90000    0   0   0   0   0
##   92000    0   0   0   1   0
##   93000    0   0   0   0   0
##   95000    2   0   0   0   0
##   96000    0   0   0   0   0
##   96500    0   0   0   0   0
##   97000    0   0   0   0   0
##   98000    1   1   0   1   0
##   99000    0   0   0   0   0
##   100000   0   0   0   1   0
##   100400   0   0   0   0   0
##   101000   0   0   0   0   0
##   101100   0   0   0   0   0
##   101600   0   0   0   0   0
##   102500   1   0   0   0   0
##   103000   0   0   0   0   0
##   104000   0   0   0   0   0
##   105000   0   1   0   0   0
##   106000   0   2   0   0   0
##   107000   0   0   0   0   0
##   107300   0   0   0   0   0
##   107500   0   0   0   0   0
##   108000   0   0   0   0   0
##   110000   0   0   0   0   0
##   112000   1   1   0   0   0
##   115000   0   0   0   1   0
##   118000   0   0   0   0   0
##   120000   1   0   1   0   0
##   126710   0   0   0   0   0
##   130000   0   0   0   0   0
##   145800   0   0   0   0   0
##   146000   0   0   0   0   0
##   162000   0   0   1   0   0
##   220000   0   0   0   0   0
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 927.24, df = 820, p-value = 0.005279

p< 0.05 suggest that is some relationship between salary and gmat total score

salary and spring average

mytable <- xtabs(~ salary+s_avg,data= mba3.df)
mytable
##         s_avg
## salary   2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.91 3 3.09 3.1 3.2 3.27 3.3 3.4
##   64000    0   0   0   0   0   0   0   0    0 0    0   0   0    0   0   0
##   77000    0   0   0   1   0   0   0   0    0 0    0   0   0    0   0   0
##   78256    0   0   0   0   0   0   0   1    0 0    0   0   0    0   0   0
##   82000    0   0   0   0   0   0   0   0    0 0    0   1   0    0   0   0
##   85000    0   0   1   0   0   0   0   0    0 0    0   0   0    0   1   0
##   86000    0   0   0   0   0   0   0   1    0 0    0   0   0    0   0   0
##   88000    0   0   0   0   0   0   0   0    0 0    0   0   0    0   0   1
##   88500    0   0   0   0   0   1   0   0    0 0    0   0   0    0   0   0
##   90000    0   0   1   0   0   1   0   1    0 0    0   0   0    0   0   0
##   92000    0   0   0   0   0   0   0   0    0 0    0   1   0    0   1   1
##   93000    0   0   0   0   0   1   0   0    0 0    0   1   0    0   0   1
##   95000    0   0   1   0   0   0   0   1    0 0    0   0   1    1   2   0
##   96000    0   0   0   1   0   0   0   0    0 0    0   0   1    0   2   0
##   96500    0   0   0   0   0   0   0   0    0 1    0   0   0    0   0   0
##   97000    0   0   0   0   0   0   1   1    0 0    0   0   0    0   0   0
##   98000    0   1   0   0   0   1   1   4    0 1    0   0   2    0   0   0
##   99000    0   0   0   0   0   0   0   0    0 0    0   1   0    0   0   0
##   100000   0   0   0   0   2   0   1   1    0 1    1   0   0    0   1   2
##   100400   0   0   0   0   1   0   0   0    0 0    0   0   0    0   0   0
##   101000   0   0   0   0   0   0   1   0    0 0    0   1   0    0   0   0
##   101100   0   0   0   0   0   0   1   0    0 0    0   0   0    0   0   0
##   101600   0   0   0   0   1   0   0   0    0 0    0   0   0    0   0   0
##   102500   0   0   0   0   0   0   1   0    0 0    0   0   0    0   0   0
##   103000   0   0   0   0   0   0   0   0    0 0    0   0   1    0   0   0
##   104000   0   0   1   0   0   0   0   0    0 0    0   0   1    0   0   0
##   105000   1   0   0   0   0   0   0   0    1 2    0   0   1    0   2   0
##   106000   0   0   0   0   0   0   0   1    0 0    0   0   0    0   0   0
##   107000   0   0   0   0   0   0   0   0    0 0    1   0   0    0   0   0
##   107300   0   0   0   0   0   0   0   1    0 0    0   0   0    0   0   0
##   107500   0   0   0   0   0   0   0   0    0 0    0   0   0    0   1   0
##   108000   0   0   0   0   0   0   0   1    0 0    0   0   0    0   0   0
##   110000   0   0   0   0   0   0   0   0    0 0    0   0   0    0   0   0
##   112000   0   0   0   0   0   0   1   0    0 0    0   1   0    0   0   0
##   115000   0   0   0   0   1   0   0   0    0 1    0   0   1    0   0   0
##   118000   0   0   0   0   0   0   0   0    0 0    0   0   0    0   0   0
##   120000   0   0   0   0   0   0   0   0    0 0    0   0   0    0   1   0
##   126710   0   0   0   0   1   0   0   0    0 0    0   0   0    0   0   0
##   130000   0   0   0   0   0   0   0   0    0 0    0   0   1    0   0   0
##   145800   0   0   0   0   0   0   0   0    0 0    0   1   0    0   0   0
##   146000   0   0   0   0   0   0   0   0    0 0    0   0   0    0   0   0
##   162000   0   0   0   0   0   0   0   0    0 0    0   0   0    0   0   0
##   220000   0   0   0   1   0   0   0   0    0 0    0   0   0    0   0   0
##         s_avg
## salary   3.45 3.5 3.6 3.7 3.8 4
##   64000     0   1   0   0   0 0
##   77000     0   0   0   0   0 0
##   78256     0   0   0   0   0 0
##   82000     0   0   0   0   0 0
##   85000     0   2   0   0   0 0
##   86000     0   1   0   0   0 0
##   88000     0   0   0   0   0 0
##   88500     0   0   0   0   0 0
##   90000     0   0   0   0   0 0
##   92000     0   0   0   0   0 0
##   93000     0   0   0   0   0 0
##   95000     0   0   1   0   0 0
##   96000     0   0   0   0   0 0
##   96500     0   0   0   0   0 0
##   97000     0   0   0   0   0 0
##   98000     0   0   0   0   0 0
##   99000     0   0   0   0   0 0
##   100000    0   0   0   0   0 0
##   100400    0   0   0   0   0 0
##   101000    0   0   0   0   0 0
##   101100    0   0   0   0   0 0
##   101600    0   0   0   0   0 0
##   102500    0   0   0   0   0 0
##   103000    0   0   0   0   0 0
##   104000    0   0   0   0   0 0
##   105000    1   1   1   0   1 0
##   106000    0   1   0   1   0 0
##   107000    0   0   0   0   0 0
##   107300    0   0   0   0   0 0
##   107500    0   0   0   0   0 0
##   108000    0   1   0   0   0 0
##   110000    0   0   1   0   0 0
##   112000    0   0   1   0   0 0
##   115000    0   0   1   1   0 0
##   118000    0   1   0   0   0 0
##   120000    0   2   0   0   1 0
##   126710    0   0   0   0   0 0
##   130000    0   0   0   0   0 0
##   145800    0   0   0   0   0 0
##   146000    0   0   0   0   0 1
##   162000    0   0   1   0   0 0
##   220000    0   0   0   0   0 0
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 792.97, df = 861, p-value = 0.9524

p> 0.05 suggest that is no relationship between salary and spring mba average

mytable <- xtabs(~ salary+f_avg,data= mba3.df)
mytable
##         f_avg
## salary   0 2 2.25 2.5 2.67 2.75 2.83 3 3.25 3.33 3.5 3.6 3.67 3.75 4
##   64000  0 0    0   0    0    0    0 0    1    0   0   0    0    0 0
##   77000  0 0    0   0    0    0    0 1    0    0   0   0    0    0 0
##   78256  0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
##   82000  0 0    0   0    0    0    0 0    0    1   0   0    0    0 0
##   85000  0 1    0   0    0    0    0 0    1    0   0   1    0    1 0
##   86000  0 0    0   0    1    0    0 0    1    0   0   0    0    0 0
##   88000  0 0    0   0    0    0    0 0    1    0   0   0    0    0 0
##   88500  0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
##   90000  0 0    1   1    0    0    0 0    1    0   0   0    0    0 0
##   92000  0 0    0   0    0    0    0 0    1    0   2   0    0    0 0
##   93000  0 0    0   0    0    1    0 1    0    0   0   0    0    1 0
##   95000  0 0    0   0    0    1    0 1    2    0   2   0    1    0 0
##   96000  0 0    0   1    0    0    0 0    2    0   1   0    0    0 0
##   96500  0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
##   97000  0 0    0   0    0    1    0 1    0    0   0   0    0    0 0
##   98000  0 0    0   1    0    2    0 2    5    0   0   0    0    0 0
##   99000  0 0    0   0    0    0    0 1    0    0   0   0    0    0 0
##   100000 0 0    0   0    0    1    0 5    1    0   1   0    1    0 0
##   100400 0 0    0   1    0    0    0 0    0    0   0   0    0    0 0
##   101000 0 0    0   0    0    0    0 1    0    0   1   0    0    0 0
##   101100 0 0    0   0    0    0    0 1    0    0   0   0    0    0 0
##   101600 0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
##   102500 0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
##   103000 0 0    0   0    0    0    0 1    0    0   0   0    0    0 0
##   104000 0 0    0   0    0    1    0 0    1    0   0   0    0    0 0
##   105000 0 1    0   0    0    0    1 3    2    0   4   0    0    0 0
##   106000 0 0    0   0    0    0    0 2    0    0   0   1    0    0 0
##   107000 0 0    0   0    0    0    0 0    0    0   1   0    0    0 0
##   107300 0 0    0   0    0    0    0 0    0    0   1   0    0    0 0
##   107500 0 0    0   0    0    0    0 0    1    0   0   0    0    0 0
##   108000 0 0    0   0    0    0    0 1    1    0   0   0    0    0 0
##   110000 0 0    0   0    0    0    0 0    0    0   1   0    0    0 0
##   112000 0 0    0   0    0    1    0 1    0    0   1   0    0    0 0
##   115000 0 0    0   1    0    0    0 1    1    0   1   0    0    0 1
##   118000 0 0    0   0    0    0    0 0    0    0   1   0    0    0 0
##   120000 0 0    0   0    0    0    0 1    2    0   0   0    0    0 1
##   126710 0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
##   130000 0 0    0   0    0    0    0 0    1    0   0   0    0    0 0
##   145800 0 0    0   0    0    0    0 1    0    0   0   0    0    0 0
##   146000 1 0    0   0    0    0    0 0    0    0   0   0    0    0 0
##   162000 0 0    0   0    0    0    0 0    0    0   0   0    0    1 0
##   220000 0 0    0   0    0    1    0 0    0    0   0   0    0    0 0
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 596.28, df = 574, p-value = 0.2518

p> 0.05 suggest that is no relationship between salary and fall mba average

mytable <- xtabs(~ salary+satis,data= mba2.df)
mytable
##         satis
## salary    3  4  5  6  7
##   0       0  4 36 40 10
##   64000   0  0  0  0  1
##   77000   0  0  0  1  0
##   78256   0  0  1  0  0
##   82000   0  0  0  0  1
##   85000   0  0  1  3  0
##   86000   0  0  2  0  0
##   88000   0  0  0  0  1
##   88500   0  0  0  1  0
##   90000   0  0  2  0  1
##   92000   0  0  1  1  1
##   93000   0  0  1  2  0
##   95000   1  1  1  2  2
##   96000   0  0  1  1  2
##   96500   0  0  0  1  0
##   97000   0  0  0  1  1
##   98000   0  0  2  5  3
##   99000   0  0  0  1  0
##   100000  0  0  1  6  2
##   100400  0  0  0  0  1
##   101000  0  0  1  1  0
##   101100  0  0  0  1  0
##   101600  0  0  0  1  0
##   102500  0  0  1  0  0
##   103000  0  0  0  1  0
##   104000  0  0  1  1  0
##   105000  0  0  4  6  1
##   106000  0  0  0  2  1
##   107000  0  0  1  0  0
##   107300  0  0  0  0  1
##   107500  0  0  1  0  0
##   108000  0  0  0  2  0
##   110000  0  0  1  0  0
##   112000  0  0  0  2  1
##   115000  0  0  3  2  0
##   118000  0  0  0  0  1
##   120000  0  0  2  2  0
##   126710  0  0  0  1  0
##   130000  0  0  0  0  1
##   145800  0  0  0  1  0
##   146000  0  0  0  1  0
##   162000  0  0  1  0  0
##   220000  0  0  0  1  0
chisq.test(mytable)
## Warning in chisq.test(mytable): Chi-squared approximation may be incorrect
## 
##  Pearson's Chi-squared test
## 
## data:  mytable
## X-squared = 126.45, df = 168, p-value = 0.9928

p> 0.05 suggest that is no relationship between salary and satisfaction

regression model

regr <- lm(salary ~ age+gmat_tot+gmat_qpc+gmat_vpc+gmat_tpc+s_avg+f_avg, data = mba3.df)
summary(regr)
## 
## Call:
## lm(formula = salary ~ age + gmat_tot + gmat_qpc + gmat_vpc + 
##     gmat_tpc + s_avg + f_avg, data = mba3.df)
## 
## Residuals:
##    Min     1Q Median     3Q    Max 
## -31186  -7438    622   5299  69725 
## 
## Coefficients:
##               Estimate Std. Error t value Pr(>|t|)    
## (Intercept) 37730.6788 43445.3073   0.868   0.3873    
## age          2657.3914   503.9286   5.273 8.39e-07 ***
## gmat_tot       -0.8982   164.7408  -0.005   0.9957    
## gmat_qpc      859.6496   480.8645   1.788   0.0770 .  
## gmat_vpc      537.0116   480.7496   1.117   0.2668    
## gmat_tpc    -1454.7911   700.5012  -2.077   0.0405 *  
## s_avg        4069.5906  4808.3606   0.846   0.3995    
## f_avg       -1827.8260  3750.0292  -0.487   0.6271    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 15290 on 95 degrees of freedom
## Multiple R-squared:  0.3181, Adjusted R-squared:  0.2679 
## F-statistic: 6.332 on 7 and 95 DF,  p-value: 4.124e-06

Since the p value of f statistics is < 0.05 the model is correct. only age is significantly affecting salary.

regr <- lm(salary ~ ., data = mba2.df)
summary(regr)
## 
## Call:
## lm(formula = salary ~ ., data = mba2.df)
## 
## Residuals:
##    Min     1Q Median     3Q    Max 
## -93297 -48384  19635  43919 182830 
## 
## Coefficients:
##             Estimate Std. Error t value Pr(>|t|)  
## (Intercept) 157118.8   109225.8   1.438   0.1520  
## age          -3827.0     1946.2  -1.966   0.0508 .
## sex           1249.6     8725.1   0.143   0.8863  
## gmat_tot      -281.8      314.3  -0.897   0.3711  
## gmat_qpc       426.5      849.9   0.502   0.6164  
## gmat_vpc       254.8      825.4   0.309   0.7579  
## gmat_tpc       570.2      651.5   0.875   0.3826  
## s_avg         8421.8    16684.6   0.505   0.6143  
## f_avg        -6198.0     8788.1  -0.705   0.4816  
## quarter      -6635.2     5147.0  -1.289   0.1990  
## work_yrs      2704.3     2197.4   1.231   0.2201  
## frstlang     14199.8    15677.4   0.906   0.3663  
## satis         9830.8     5193.4   1.893   0.0600 .
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 52350 on 180 degrees of freedom
## Multiple R-squared:  0.09076,    Adjusted R-squared:  0.03015 
## F-statistic: 1.497 on 12 and 180 DF,  p-value: 0.1285

p value of f statistics is more so the model is rejected

for not placed students

salary and gender

t.test(mba4.df$salary, mba4.df$sex)
## 
##  Welch Two Sample t-test
## 
## data:  mba4.df$salary and mba4.df$sex
## t = -27.156, df = 89, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -1.347422 -1.163689
## sample estimates:
## mean of x mean of y 
##  0.000000  1.255556

p< 0.05 therefor it seems there is a relation

Salary and first language

t.test(mba4.df$salary, mba4.df$frstlang)
## 
##  Welch Two Sample t-test
## 
## data:  mba4.df$salary and mba4.df$frstlang
## t = -36.097, df = 89, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -1.148828 -1.028950
## sample estimates:
## mean of x mean of y 
##  0.000000  1.088889

p< 0.05 therefor it seems there is a relation

salary and work experiance

t.test(mba4.df$salary, mba4.df$work_yrs)
## 
##  Welch Two Sample t-test
## 
## data:  mba4.df$salary and mba4.df$work_yrs
## t = -10.117, df = 89, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -5.490102 -3.687675
## sample estimates:
## mean of x mean of y 
##  0.000000  4.588889

p< 0.05 therefor it seems there is a relation

salary and total gmat

t.test(mba4.df$salary, mba4.df$gmat_tot)
## 
##  Welch Two Sample t-test
## 
## data:  mba4.df$salary and mba4.df$gmat_tot
## t = -92.723, df = 89, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -627.4979 -601.1687
## sample estimates:
## mean of x mean of y 
##    0.0000  614.3333