Assignment #1 Caroline Hawkins Data Analytics - Summer 2018
The three main measures of central tendency are the mode, the median and the mean. The median is the preferred method of central tendency because it is less affected by outliers and skewed data. A real world example is compensation studies, using median would not factor in how some companies pay unreasonably high salaries and instead use more of the benchmark.
A vector is a collection of objects that can be stored in a single variable and accessed through subscripts. The different ways to create a vector in R are the following: • B = C(1,2,3,4,5) • x5<1:16;x • x2 <- c(1, 7.4, TRUE, “hello”) • Seq(1,5,by=0.2) • Seq(1,5,length.out=4)
Vec1
[1] "X^3" "1" "3" "5" "7" "9" "2" "4" "6"
[10] "8" "10"
x<-seq(1,by=2,len=100) x [1] 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 [17] 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 [33] 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 [49] 97 99 101 103 105 107 109 111 113 115 117 119 121 123 125 127 [65] 129 131 133 135 137 139 141 143 145 147 149 151 153 155 157 159 [81] 161 163 165 167 169 171 173 175 177 179 181 183 185 187 189 191 [97] 193 195 197 199
x[-(60:80)][1] 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 [17] 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 [33] 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 [49] 97 99 101 103 105 107 109 111 113 115 117 161 163 165 167 169 [65] 171 173 175 177 179 181 183 185 187 189 191 193 195 197 199
sd(x)
[1] 4.84768
mean(x)
[1] 6
median(x)
[1] 5
mat1=matrix(x1, ncol=3)
mat1
[,1] [,2] [,3]
[1,] 2 1 3
[2,] 3 6 5
[3,] 7 2 1
mat2=matrix(x1,nrow=3)
mat2
[,1] [,2] [,3]
[1,] 2 1 3
[2,] 3 6 5
[3,] 7 2 1
mat3=matrix(x2, ncol=3)
mat3
[,1] [,2] [,3]
[1,] 3 0 5
[2,] 2 7 8
[3,] 9 8 2
mat4=matrix(x2, nrow=3)
mat4
[,1] [,2] [,3]
[1,] 3 0 5
[2,] 2 7 8
[3,] 9 8 2
(x1%*%x2)
[,1]
[1,] 190
class(iris)
[1] "data.frame"
summary(iris)
Sepal.Length Sepal.Width Petal.Length
Min. :4.300 Min. :2.000 Min. :1.000
1st Qu.:5.100 1st Qu.:2.800 1st Qu.:1.600
Median :5.800 Median :3.000 Median :4.350
Mean :5.843 Mean :3.057 Mean :3.758
3rd Qu.:6.400 3rd Qu.:3.300 3rd Qu.:5.100
Max. :7.900 Max. :4.400 Max. :6.900
Petal.Width Species
Min. :0.100 setosa :50
1st Qu.:0.300 versicolor:50
Median :1.300 virginica :50
Mean :1.199
3rd Qu.:1.800
Max. :2.500
rownames(iris)
[1] "1" "2" "3" "4" "5" "6" "7" "8" "9"
[10] "10" "11" "12" "13" "14" "15" "16" "17" "18"
[19] "19" "20" "21" "22" "23" "24" "25" "26" "27"
[28] "28" "29" "30" "31" "32" "33" "34" "35" "36"
[37] "37" "38" "39" "40" "41" "42" "43" "44" "45"
[46] "46" "47" "48" "49" "50" "51" "52" "53" "54"
[55] "55" "56" "57" "58" "59" "60" "61" "62" "63"
[64] "64" "65" "66" "67" "68" "69" "70" "71" "72"
[73] "73" "74" "75" "76" "77" "78" "79" "80" "81"
[82] "82" "83" "84" "85" "86" "87" "88" "89" "90"
[91] "91" "92" "93" "94" "95" "96" "97" "98" "99"
[100] "100" "101" "102" "103" "104" "105" "106" "107" "108"
[109] "109" "110" "111" "112" "113" "114" "115" "116" "117"
[118] "118" "119" "120" "121" "122" "123" "124" "125" "126"
[127] "127" "128" "129" "130" "131" "132" "133" "134" "135"
[136] "136" "137" "138" "139" "140" "141" "142" "143" "144"
[145] "145" "146" "147" "148" "149" "150"
colnames(iris)
[1] "Sepal.Length" "Sepal.Width" "Petal.Length"
[4] "Petal.Width" "Species"
row(iris)
[,1] [,2] [,3] [,4] [,5]
[1,] 1 1 1 1 1
[2,] 2 2 2 2 2
[3,] 3 3 3 3 3
[4,] 4 4 4 4 4
[5,] 5 5 5 5 5
[6,] 6 6 6 6 6
[7,] 7 7 7 7 7
[8,] 8 8 8 8 8
[9,] 9 9 9 9 9
[10,] 10 10 10 10 10
[11,] 11 11 11 11 11
[12,] 12 12 12 12 12
[13,] 13 13 13 13 13
[14,] 14 14 14 14 14
[15,] 15 15 15 15 15
[16,] 16 16 16 16 16
[17,] 17 17 17 17 17
[18,] 18 18 18 18 18
[19,] 19 19 19 19 19
[20,] 20 20 20 20 20
[21,] 21 21 21 21 21
[22,] 22 22 22 22 22
[23,] 23 23 23 23 23
[24,] 24 24 24 24 24
[25,] 25 25 25 25 25
[26,] 26 26 26 26 26
[27,] 27 27 27 27 27
[28,] 28 28 28 28 28
[29,] 29 29 29 29 29
[30,] 30 30 30 30 30
[31,] 31 31 31 31 31
[32,] 32 32 32 32 32
[33,] 33 33 33 33 33
[34,] 34 34 34 34 34
[35,] 35 35 35 35 35
[36,] 36 36 36 36 36
[37,] 37 37 37 37 37
[38,] 38 38 38 38 38
[39,] 39 39 39 39 39
[40,] 40 40 40 40 40
[41,] 41 41 41 41 41
[42,] 42 42 42 42 42
[43,] 43 43 43 43 43
[44,] 44 44 44 44 44
[45,] 45 45 45 45 45
[46,] 46 46 46 46 46
[47,] 47 47 47 47 47
[48,] 48 48 48 48 48
[49,] 49 49 49 49 49
[50,] 50 50 50 50 50
[51,] 51 51 51 51 51
[52,] 52 52 52 52 52
[53,] 53 53 53 53 53
[54,] 54 54 54 54 54
[55,] 55 55 55 55 55
[56,] 56 56 56 56 56
[57,] 57 57 57 57 57
[58,] 58 58 58 58 58
[59,] 59 59 59 59 59
[60,] 60 60 60 60 60
[61,] 61 61 61 61 61
[62,] 62 62 62 62 62
[63,] 63 63 63 63 63
[64,] 64 64 64 64 64
[65,] 65 65 65 65 65
[66,] 66 66 66 66 66
[67,] 67 67 67 67 67
[68,] 68 68 68 68 68
[69,] 69 69 69 69 69
[70,] 70 70 70 70 70
[71,] 71 71 71 71 71
[72,] 72 72 72 72 72
[73,] 73 73 73 73 73
[74,] 74 74 74 74 74
[75,] 75 75 75 75 75
[76,] 76 76 76 76 76
[77,] 77 77 77 77 77
[78,] 78 78 78 78 78
[79,] 79 79 79 79 79
[80,] 80 80 80 80 80
[81,] 81 81 81 81 81
[82,] 82 82 82 82 82
[83,] 83 83 83 83 83
[84,] 84 84 84 84 84
[85,] 85 85 85 85 85
[86,] 86 86 86 86 86
[87,] 87 87 87 87 87
[88,] 88 88 88 88 88
[89,] 89 89 89 89 89
[90,] 90 90 90 90 90
[91,] 91 91 91 91 91
[92,] 92 92 92 92 92
[93,] 93 93 93 93 93
[94,] 94 94 94 94 94
[95,] 95 95 95 95 95
[96,] 96 96 96 96 96
[97,] 97 97 97 97 97
[98,] 98 98 98 98 98
[99,] 99 99 99 99 99
[100,] 100 100 100 100 100
[101,] 101 101 101 101 101
[102,] 102 102 102 102 102
[103,] 103 103 103 103 103
[104,] 104 104 104 104 104
[105,] 105 105 105 105 105
[106,] 106 106 106 106 106
[107,] 107 107 107 107 107
[108,] 108 108 108 108 108
[109,] 109 109 109 109 109
[110,] 110 110 110 110 110
[111,] 111 111 111 111 111
[112,] 112 112 112 112 112
[113,] 113 113 113 113 113
[114,] 114 114 114 114 114
[115,] 115 115 115 115 115
[116,] 116 116 116 116 116
[117,] 117 117 117 117 117
[118,] 118 118 118 118 118
[119,] 119 119 119 119 119
[120,] 120 120 120 120 120
[121,] 121 121 121 121 121
[122,] 122 122 122 122 122
[123,] 123 123 123 123 123
[124,] 124 124 124 124 124
[125,] 125 125 125 125 125
[126,] 126 126 126 126 126
[127,] 127 127 127 127 127
[128,] 128 128 128 128 128
[129,] 129 129 129 129 129
[130,] 130 130 130 130 130
[131,] 131 131 131 131 131
[132,] 132 132 132 132 132
[133,] 133 133 133 133 133
[134,] 134 134 134 134 134
[135,] 135 135 135 135 135
[136,] 136 136 136 136 136
[137,] 137 137 137 137 137
[138,] 138 138 138 138 138
[139,] 139 139 139 139 139
[140,] 140 140 140 140 140
[141,] 141 141 141 141 141
[142,] 142 142 142 142 142
[143,] 143 143 143 143 143
[144,] 144 144 144 144 144
[145,] 145 145 145 145 145
[146,] 146 146 146 146 146
[147,] 147 147 147 147 147
[148,] 148 148 148 148 148
[149,] 149 149 149 149 149
[150,] 150 150 150 150 150
col(iris)
[,1] [,2] [,3] [,4] [,5]
[1,] 1 2 3 4 5
[2,] 1 2 3 4 5
[3,] 1 2 3 4 5
[4,] 1 2 3 4 5
[5,] 1 2 3 4 5
[6,] 1 2 3 4 5
[7,] 1 2 3 4 5
[8,] 1 2 3 4 5
[9,] 1 2 3 4 5
[10,] 1 2 3 4 5
[11,] 1 2 3 4 5
[12,] 1 2 3 4 5
[13,] 1 2 3 4 5
[14,] 1 2 3 4 5
[15,] 1 2 3 4 5
[16,] 1 2 3 4 5
[17,] 1 2 3 4 5
[18,] 1 2 3 4 5
[19,] 1 2 3 4 5
[20,] 1 2 3 4 5
[21,] 1 2 3 4 5
[22,] 1 2 3 4 5
[23,] 1 2 3 4 5
[24,] 1 2 3 4 5
[25,] 1 2 3 4 5
[26,] 1 2 3 4 5
[27,] 1 2 3 4 5
[28,] 1 2 3 4 5
[29,] 1 2 3 4 5
[30,] 1 2 3 4 5
[31,] 1 2 3 4 5
[32,] 1 2 3 4 5
[33,] 1 2 3 4 5
[34,] 1 2 3 4 5
[35,] 1 2 3 4 5
[36,] 1 2 3 4 5
[37,] 1 2 3 4 5
[38,] 1 2 3 4 5
[39,] 1 2 3 4 5
[40,] 1 2 3 4 5
[41,] 1 2 3 4 5
[42,] 1 2 3 4 5
[43,] 1 2 3 4 5
[44,] 1 2 3 4 5
[45,] 1 2 3 4 5
[46,] 1 2 3 4 5
[47,] 1 2 3 4 5
[48,] 1 2 3 4 5
[49,] 1 2 3 4 5
[50,] 1 2 3 4 5
[51,] 1 2 3 4 5
[52,] 1 2 3 4 5
[53,] 1 2 3 4 5
[54,] 1 2 3 4 5
[55,] 1 2 3 4 5
[56,] 1 2 3 4 5
[57,] 1 2 3 4 5
[58,] 1 2 3 4 5
[59,] 1 2 3 4 5
[60,] 1 2 3 4 5
[61,] 1 2 3 4 5
[62,] 1 2 3 4 5
[63,] 1 2 3 4 5
[64,] 1 2 3 4 5
[65,] 1 2 3 4 5
[66,] 1 2 3 4 5
[67,] 1 2 3 4 5
[68,] 1 2 3 4 5
[69,] 1 2 3 4 5
[70,] 1 2 3 4 5
[71,] 1 2 3 4 5
[72,] 1 2 3 4 5
[73,] 1 2 3 4 5
[74,] 1 2 3 4 5
[75,] 1 2 3 4 5
[76,] 1 2 3 4 5
[77,] 1 2 3 4 5
[78,] 1 2 3 4 5
[79,] 1 2 3 4 5
[80,] 1 2 3 4 5
[81,] 1 2 3 4 5
[82,] 1 2 3 4 5
[83,] 1 2 3 4 5
[84,] 1 2 3 4 5
[85,] 1 2 3 4 5
[86,] 1 2 3 4 5
[87,] 1 2 3 4 5
[88,] 1 2 3 4 5
[89,] 1 2 3 4 5
[90,] 1 2 3 4 5
[91,] 1 2 3 4 5
[92,] 1 2 3 4 5
[93,] 1 2 3 4 5
[94,] 1 2 3 4 5
[95,] 1 2 3 4 5
[96,] 1 2 3 4 5
[97,] 1 2 3 4 5
[98,] 1 2 3 4 5
[99,] 1 2 3 4 5
[100,] 1 2 3 4 5
[101,] 1 2 3 4 5
[102,] 1 2 3 4 5
[103,] 1 2 3 4 5
[104,] 1 2 3 4 5
[105,] 1 2 3 4 5
[106,] 1 2 3 4 5
[107,] 1 2 3 4 5
[108,] 1 2 3 4 5
[109,] 1 2 3 4 5
[110,] 1 2 3 4 5
[111,] 1 2 3 4 5
[112,] 1 2 3 4 5
[113,] 1 2 3 4 5
[114,] 1 2 3 4 5
[115,] 1 2 3 4 5
[116,] 1 2 3 4 5
[117,] 1 2 3 4 5
[118,] 1 2 3 4 5
[119,] 1 2 3 4 5
[120,] 1 2 3 4 5
[121,] 1 2 3 4 5
[122,] 1 2 3 4 5
[123,] 1 2 3 4 5
[124,] 1 2 3 4 5
[125,] 1 2 3 4 5
[126,] 1 2 3 4 5
[127,] 1 2 3 4 5
[128,] 1 2 3 4 5
[129,] 1 2 3 4 5
[130,] 1 2 3 4 5
[131,] 1 2 3 4 5
[132,] 1 2 3 4 5
[133,] 1 2 3 4 5
[134,] 1 2 3 4 5
[135,] 1 2 3 4 5
[136,] 1 2 3 4 5
[137,] 1 2 3 4 5
[138,] 1 2 3 4 5
[139,] 1 2 3 4 5
[140,] 1 2 3 4 5
[141,] 1 2 3 4 5
[142,] 1 2 3 4 5
[143,] 1 2 3 4 5
[144,] 1 2 3 4 5
[145,] 1 2 3 4 5
[146,] 1 2 3 4 5
[147,] 1 2 3 4 5
[148,] 1 2 3 4 5
[149,] 1 2 3 4 5
[150,] 1 2 3 4 5
iris[(149:150)]