Membangkitkan Data

skenario

Y: Keputusan yang bernilai 1 untuk membeli dan 0 untuk tidak membeli X1: usia X2: pendapatan bulanan X3: Pekerjaan yang terdiri 8 kategori X4: Tingkat Pendidikan bernilai 1 untuk lulus kuliah dan 0 untuk lulus SMA/SMK tidak lulus kuliah

Membangkitkan Data X1

X1 :membangkitkan 100 angka acak uniform rentang 18-55(usia) nilai tengah 20 dan banyak pembeli adalah 100

set.seed(100)
n <-100
u <-runif(n)

X1 <- round(100*(-log(1-u)/20))
X1
##   [1]  2  1  4  0  3  3  8  2  4  1  5 11  2  3  7  6  1  2  2  6  4  6  4  7  3
##  [26]  1  7 11  4  2  3 13  2 15  6 11  1  5 23  1  2 10  8  9  5  3  8 11  1  2
##  [51]  2  1  1  2  4  1  1  1  5  1  3  5 16  6  3  2  3  3  1  6  3  2  4 17  5
##  [76]  5 10  7  9  0  3  5 13 20  0  4  7  1  2  7 12  1  2  3 12  2  4  1  0  7

Membangkitkan Data X2

X2:membangkitkan 100 angka acak normal rataan 3000 dan varians 1000 (pendapatan)

X2 <- round(rnorm(n,100,3000),1000)
X2
##   [1] -1241.18655 -5115.79384   636.59455  5792.39710 -6715.77646  3041.39242
##   [7] -4096.47685  5574.61727  4243.89619 -2416.55563  -685.98732  -106.53208
##  [13] -1036.65067  7845.87678   489.50241 -2039.07494  2013.98273   705.07477
##  [19]  -109.75084  -177.46963  1446.70982 -3093.06701 -3387.25797  5045.56524
##  [25] -6086.28806   138.24916 -3162.58505   911.61848  3125.35562 -6123.21426
##  [31]  2790.46682   -49.98730 -3936.04793 -5693.63460  2228.74475  -373.71510
##  [37]   749.10362  2552.08623  5281.52726  -211.31088 -1571.36687  4384.90429
##  [43] -2578.87221 -3372.71372 -1490.88936  7437.04827 -2397.48739  1340.55955
##  [49] -3436.04942 -3422.10428  -898.77005  4189.34112 -1307.44202  2628.62690
##  [55] -4273.98117 -1100.91776 -2229.25186 -1007.88953  3820.30438  -222.30143
##  [61]   617.78052   863.80380 -1743.60149 -4187.64529  -892.92630   485.15819
##  [67]  3154.35998  -666.72107  -807.62303  4945.57205 -2221.14006  1372.00720
##  [73] -1651.84094  1345.10704 -4535.78497 -1456.24851  -739.37466  3122.37215
##  [79] -1308.70986   993.69112 -1153.38330 -2451.14233  2167.13858 -1280.58858
##  [85]  4144.55313  1429.21415  -352.77857  1466.64657   -20.46404  1468.36313
##  [91] -1125.27509 -6309.48157   570.46575  2080.14670 -2845.50324 -3240.93111
##  [97] -1212.04303 -1448.33374  1356.98797   502.46631

Membangkitkan Data X3

X3: membangkitkan angka acak 1 sampai 8 sebanyak 100 (kategori pekerjaan)

X3 = sample(c(1:8),size=100,replace=TRUE)
X3
##   [1] 7 2 6 3 3 4 8 2 4 4 7 1 3 1 3 8 2 8 7 4 8 7 7 1 6 3 7 3 1 2 1 2 5 2 6 8 4
##  [38] 7 4 1 1 7 7 5 7 3 1 7 3 4 5 5 5 5 8 2 5 8 6 6 8 5 5 2 3 5 5 7 2 7 7 1 7 8
##  [75] 1 7 8 3 4 4 3 5 7 4 7 3 8 8 2 1 7 2 4 1 8 3 5 3 8 7

Membangkitkan Data X4

X4: Tingkat pendidikan keterangan yang digunakan (0= lulus SMA/Tidak kuliah) dan (1= lulus kuliah)

set.seed(111)
X4 <- round(runif(n))
X4
##   [1] 1 1 0 1 0 0 0 1 0 0 1 1 0 0 0 0 0 1 0 1 0 0 0 0 1 0 1 0 1 1 0 1 0 0 0 1 0
##  [38] 1 1 1 1 0 1 1 1 0 0 1 1 1 1 1 0 0 1 1 1 0 0 1 0 0 0 0 1 0 0 0 0 0 1 1 0 0
##  [75] 1 0 0 1 0 1 0 1 0 0 0 0 1 1 1 1 1 1 1 1 1 0 1 0 1 1

Membangkit data Y

menentukan koefisien

b0 <-  11
b1 <-  3.5
b2 <-  0.05
b3 <-  1.26
b4 <-  3.2
set.seed(1)
datapendukung <- b0+(b1*X1)+(b2*X2)+(b3*X3)+(b4*X4)
datapendukung
##   [1]  -32.039327 -235.569692   64.389727  307.599855 -310.508823  178.609621
##   [7] -155.743842  302.450863  242.234809 -101.287781    6.220634   48.633396
##  [13]  -30.052533  415.053839   63.755121  -59.873747  117.719136   66.533739
##  [19]   21.332458   31.366519  107.415491 -113.833351 -135.542898  289.038262
##  [25] -272.054403   25.192458 -110.609252   98.860924  185.727781 -282.440713
##  [31]  162.283341   59.720635 -172.502397 -218.661730  150.997238   44.094245
##  [37]   56.995181  168.124311  363.816363    8.394456  -56.108344  274.065214
##  [43]  -77.923610 -116.635686  -34.024468  397.132414  -79.614370  128.547977
##  [49] -150.322471 -144.865214  -17.438503  233.467056  -44.572101  155.731345
##  [55] -175.419058  -34.825888  -87.462593  -25.814477  227.075219   14.144929
##  [61]   62.469026   77.990190  -13.880074 -174.862264  -16.166315   48.557910
##  [67]  185.517999   -3.016054  -23.361152  288.098602  -77.537003   91.060360
##  [73]  -48.772047  147.835352 -193.829248  -35.492426   19.111267  198.598607
##  [79]  -17.895493   68.924556  -32.389165  -84.557116  173.676929   22.010571
##  [85]  227.047657  100.240708   31.141072  101.112329   22.696798  113.378157
##  [91]    8.756246 -295.254078   54.763287  129.967335  -75.995162 -140.266556
##  [97]  -26.102152  -54.136687   92.129399   72.643316
p <- exp(datapendukung)/(1+exp(datapendukung))
p
##   [1]  1.217578e-14 4.936085e-103  1.000000e+00  1.000000e+00 1.405179e-135
##   [6]  1.000000e+00  2.297781e-68  1.000000e+00  1.000000e+00  1.026303e-44
##  [11]  9.980160e-01  1.000000e+00  8.878724e-14  1.000000e+00  1.000000e+00
##  [16]  9.934867e-27  1.000000e+00  1.000000e+00  1.000000e+00  1.000000e+00
##  [21]  1.000000e+00  3.654298e-50  1.362910e-59  1.000000e+00 7.051379e-119
##  [26]  1.000000e+00  9.183580e-49  1.000000e+00  1.000000e+00 2.175489e-123
##  [31]  1.000000e+00  1.000000e+00  1.211047e-75  1.087470e-95  1.000000e+00
##  [36]  1.000000e+00  1.000000e+00  1.000000e+00  1.000000e+00  9.997739e-01
##  [41]  4.289987e-25  1.000000e+00  1.439481e-34  2.216997e-51  1.672481e-15
##  [46]  1.000000e+00  2.654108e-35  1.000000e+00  5.197330e-66  1.218532e-63
##  [51]  2.670266e-08  1.000000e+00  4.391193e-20  1.000000e+00  6.553464e-77
##  [56]  7.504280e-16  1.036283e-38  6.150568e-12  1.000000e+00  9.999993e-01
##  [61]  1.000000e+00  1.000000e+00  9.374754e-07  1.143625e-76  9.529245e-08
##  [66]  1.000000e+00  1.000000e+00  4.670587e-02  7.151230e-11  1.000000e+00
##  [71]  2.118885e-34  1.000000e+00  6.585201e-22  1.000000e+00  6.622576e-85
##  [76]  3.853323e-16  1.000000e+00  1.000000e+00  1.690776e-08  1.000000e+00
##  [81]  8.581523e-15  1.893699e-37  1.000000e+00  1.000000e+00  1.000000e+00
##  [86]  1.000000e+00  1.000000e+00  1.000000e+00  1.000000e+00  1.000000e+00
##  [91]  9.998426e-01 5.926292e-129  1.000000e+00  1.000000e+00  9.901945e-34
##  [96]  1.210623e-61  4.612959e-12  3.081311e-24  1.000000e+00  1.000000e+00
set.seed(1234)
y <- rbinom(n,1,p)
y
##   [1] 0 0 1 1 0 1 0 1 1 0 1 1 0 1 1 0 1 1 1 1 1 0 0 1 0 1 0 1 1 0 1 1 0 0 1 1 1
##  [38] 1 1 1 0 1 0 0 0 1 0 1 0 0 0 1 0 1 0 0 0 0 1 1 1 1 0 0 0 1 1 0 0 1 0 1 0 1
##  [75] 0 0 1 1 0 1 0 0 1 1 1 1 1 1 1 1 1 0 1 1 0 0 0 0 1 1
datagab <- data.frame(y,X1,X2,X3,X4)
datagab
##     y X1          X2 X3 X4
## 1   0  2 -1241.18655  7  1
## 2   0  1 -5115.79384  2  1
## 3   1  4   636.59455  6  0
## 4   1  0  5792.39710  3  1
## 5   0  3 -6715.77646  3  0
## 6   1  3  3041.39242  4  0
## 7   0  8 -4096.47685  8  0
## 8   1  2  5574.61727  2  1
## 9   1  4  4243.89619  4  0
## 10  0  1 -2416.55563  4  0
## 11  1  5  -685.98732  7  1
## 12  1 11  -106.53208  1  1
## 13  0  2 -1036.65067  3  0
## 14  1  3  7845.87678  1  0
## 15  1  7   489.50241  3  0
## 16  0  6 -2039.07494  8  0
## 17  1  1  2013.98273  2  0
## 18  1  2   705.07477  8  1
## 19  1  2  -109.75084  7  0
## 20  1  6  -177.46963  4  1
## 21  1  4  1446.70982  8  0
## 22  0  6 -3093.06701  7  0
## 23  0  4 -3387.25797  7  0
## 24  1  7  5045.56524  1  0
## 25  0  3 -6086.28806  6  1
## 26  1  1   138.24916  3  0
## 27  0  7 -3162.58505  7  1
## 28  1 11   911.61848  3  0
## 29  1  4  3125.35562  1  1
## 30  0  2 -6123.21426  2  1
## 31  1  3  2790.46682  1  0
## 32  1 13   -49.98730  2  1
## 33  0  2 -3936.04793  5  0
## 34  0 15 -5693.63460  2  0
## 35  1  6  2228.74475  6  0
## 36  1 11  -373.71510  8  1
## 37  1  1   749.10362  4  0
## 38  1  5  2552.08623  7  1
## 39  1 23  5281.52726  4  1
## 40  1  1  -211.31088  1  1
## 41  0  2 -1571.36687  1  1
## 42  1 10  4384.90429  7  0
## 43  0  8 -2578.87221  7  1
## 44  0  9 -3372.71372  5  1
## 45  0  5 -1490.88936  7  1
## 46  1  3  7437.04827  3  0
## 47  0  8 -2397.48739  1  0
## 48  1 11  1340.55955  7  1
## 49  0  1 -3436.04942  3  1
## 50  0  2 -3422.10428  4  1
## 51  0  2  -898.77005  5  1
## 52  1  1  4189.34112  5  1
## 53  0  1 -1307.44202  5  0
## 54  1  2  2628.62690  5  0
## 55  0  4 -4273.98117  8  1
## 56  0  1 -1100.91776  2  1
## 57  0  1 -2229.25186  5  1
## 58  0  1 -1007.88953  8  0
## 59  1  5  3820.30438  6  0
## 60  1  1  -222.30143  6  1
## 61  1  3   617.78052  8  0
## 62  1  5   863.80380  5  0
## 63  0 16 -1743.60149  5  0
## 64  0  6 -4187.64529  2  0
## 65  0  3  -892.92630  3  1
## 66  1  2   485.15819  5  0
## 67  1  3  3154.35998  5  0
## 68  0  3  -666.72107  7  0
## 69  0  1  -807.62303  2  0
## 70  1  6  4945.57205  7  0
## 71  0  3 -2221.14006  7  1
## 72  1  2  1372.00720  1  1
## 73  0  4 -1651.84094  7  0
## 74  1 17  1345.10704  8  0
## 75  0  5 -4535.78497  1  1
## 76  0  5 -1456.24851  7  0
## 77  1 10  -739.37466  8  0
## 78  1  7  3122.37215  3  1
## 79  0  9 -1308.70986  4  0
## 80  1  0   993.69112  4  1
## 81  0  3 -1153.38330  3  0
## 82  0  5 -2451.14233  5  1
## 83  1 13  2167.13858  7  0
## 84  1 20 -1280.58858  4  0
## 85  1  0  4144.55313  7  0
## 86  1  4  1429.21415  3  0
## 87  1  7  -352.77857  8  1
## 88  1  1  1466.64657  8  1
## 89  1  2   -20.46404  2  1
## 90  1  7  1468.36313  1  1
## 91  1 12 -1125.27509  7  1
## 92  0  1 -6309.48157  2  1
## 93  1  2   570.46575  4  1
## 94  1  3  2080.14670  1  1
## 95  0 12 -2845.50324  8  1
## 96  0  2 -3240.93111  3  0
## 97  0  4 -1212.04303  5  1
## 98  0  1 -1448.33374  3  0
## 99  1  0  1356.98797  8  1
## 100 1  7   502.46631  7  1
datasim = data.frame(y,X1,X2,X3)
View(datasim)

Analisis Regresi Logistik

modelreglog <- glm(y ~ X1 + X2 + X3 + X4, family = binomial(link="logit"),data=datagab)
## Warning: glm.fit: algorithm did not converge
## Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred
summary(modelreglog)
## 
## Call:
## glm(formula = y ~ X1 + X2 + X3 + X4, family = binomial(link = "logit"), 
##     data = datagab)
## 
## Coefficients:
##               Estimate Std. Error z value Pr(>|z|)
## (Intercept) -5.604e-01  2.461e+04   0.000    1.000
## X1           6.356e+00  3.766e+03   0.002    0.999
## X2           8.327e-02  2.206e+01   0.004    0.997
## X3           2.459e+00  4.109e+03   0.001    1.000
## X4           2.906e+01  1.951e+04   0.001    0.999
## 
## (Dispersion parameter for binomial family taken to be 1)
## 
##     Null deviance: 1.3719e+02  on 99  degrees of freedom
## Residual deviance: 2.6550e-08  on 95  degrees of freedom
## AIC: 10
## 
## Number of Fisher Scoring iterations: 25

Kesimpulan : Kesimpulan dari skenario di atas yang menunjukan bahwa X1 dan X4 signifikan terhadap model adalah bahwa usia dan tingkat pendidikan pembeli memiliki hubungan signifikan dengan keputusan pembelian. Usia pembeli juga memiliki hubungan signifikan dengan keputusan pembelian. Hal ini mengindikasikan bahwa usia dan tingkat pendidikan pembeli adalah faktor yang mempengaruhi keputusan pembelian. Pendapatan bulanan, yang ditunjukkan dalam X2, tidak signifikan terhadap model, sehingga tidak memiliki hubungan signifikan dengan keputusan pembelian. Pekerjaan, yang ditunjukkan dalam X3, juga tidak signifikan terhadap model, sehingga tidak memiliki hubungan signifikan dengan keputusan pembelian.