# Membuat data mahasiswa
No <- 1:100

Nama <- c(
"Aatirah Zuyyin","Abidah Zubair","Afifah Yamini","Afnan Wasima","Alishba Wajizah",
"Arfathan Yassar","Arrazi Yaqdhan","Bahira Uzdah","Bari’ah Unaisah","Busyra Tsabitah",
"Cordelia Tahsina","Daiyan Usaim","Dikara Umair","Diyanah Sakhi","Dzafri Ulwan",
"Dzakwaan Ukasya","Emran Tau`iid","Emyr Tasadduq","Erzhan Tarannum","Faaruuq Taheem",
"Fadhal Taamir","Faraj Sarfraz","Fathansyah Saqer","Fathinah Qismina","Fildzhah Qamira",
"Gamya Saabiq","Ghaisan Rasya","Ghaniyyah Orzala","Ghazi Raidu","Ghaziyah Ojaala",
"Ghina Oamra","Haatim Raaghiib","Habrizi Qashash","Haldis Qadir","Hana Nafhah",
"Hanania Nadhirah","Hanunah Nabila","Izzati Lubna","Jaffan Owais","Jaiz Osama",
"Jajmi Omran","Kalifa Kayesa","Kanz Nabih","Kayesa Kalifa","Kazim mulia",
"Khansa Juhairah","Lahfah Jannah","Laila Jameela","Laiq Mabkhut","Latif Ma’arif",
"Laziz Luzman","Itizam Luthfan","Maazin Laith","Mahdyah Iklilah","Malihah Ibnatu",
"Manaf kemenangan","Mazaya Hazimah","Naayif Kaysan","Nabih Kanz","Naflah Halwa",
"Nahdan Kalil","Nailah Haida","Nuha Hafsha","Obaid Jawad","Ouarda Ghaliyatul",
"Qabil Hibrizi","Qafiya Finna","Qahhar Hafizhani","Qarirah Fayza","Qudamah Haaziq",
"Raeef Gulzar","Rahadatu Ezzah","Rakhan Ghauth","Ramizah Erina","Sadira Eijaz",
"Sakhi Diyanah","Setia Fahriza","Shakhar Fahd","Syahmina Dairah","Talita Chayra",
"Tamima Chayra","Tanvir Esad","Tasadduq Emyr","Thafana Chairunnisa","Udayl Efendy",
"Ulwan Dilawar","Uqbah Daniyal","Utsratun Bahiyya","Uwais Carim","Varisha Athifah",
"Varten Bilfaqih","Velid bijak","Wafiyya Aniq","Wafiyyati Aliza","Wail Bashra",
"Wasima Afnan","Xaquille Atthallah","Yafizhan Asraf","Yang Arsalan","Yassar Arfathan"
)

JenisKelamin <- c(
"Perempuan","Laki-laki","Perempuan","Perempuan","Perempuan",
"Laki-laki","Laki-laki","Perempuan","Perempuan","Perempuan",
"Perempuan","Laki-laki","Laki-laki","Perempuan","Laki-laki",
"Laki-laki","Laki-laki","Laki-laki","Laki-laki","Laki-laki",
"Laki-laki","Laki-laki","Laki-laki","Perempuan","Perempuan",
"Laki-laki","Laki-laki","Perempuan","Laki-laki","Perempuan",
"Perempuan","Laki-laki","Laki-laki","Laki-laki","Perempuan",
"Perempuan","Perempuan","Perempuan","Laki-laki","Laki-laki",
"Laki-laki","Perempuan","Laki-laki","Perempuan","Laki-laki",
"Perempuan","Perempuan","Perempuan","Laki-laki","Laki-laki",
"Laki-laki","Laki-laki","Laki-laki","Perempuan","Perempuan",
"Laki-laki","Perempuan","Laki-laki","Laki-laki","Perempuan",
"Laki-laki","Perempuan","Perempuan","Laki-laki","Perempuan",
"Laki-laki","Perempuan","Laki-laki","Perempuan","Laki-laki",
"Laki-laki","Perempuan","Laki-laki","Perempuan","Perempuan",
"Perempuan","Laki-laki","Laki-laki","Perempuan","Perempuan",
"Perempuan","Laki-laki","Laki-laki","Perempuan","Laki-laki",
"Laki-laki","Laki-laki","Perempuan","Laki-laki","Perempuan",
"Laki-laki","Laki-laki","Perempuan","Perempuan","Laki-laki",
"Perempuan","Laki-laki","Laki-laki","Laki-laki","Laki-laki"
)

Usia <- c(
29,25,32,32,28,25,32,26,30,28,
30,27,33,30,24,26,27,26,32,28,
25,26,33,30,30,27,31,26,24,33,
31,30,24,31,24,25,28,28,26,24,
24,27,32,33,27,28,33,28,31,33,
24,29,28,29,27,31,33,31,31,32,
32,32,28,26,24,31,33,25,27,24,
27,29,28,28,25,33,33,24,33,28,
27,24,26,24,29,31,25,25,29,30,
33,26,33,27,30,29,27,31,24,32
)

data_mahasiswa <- data.frame(No,Nama,JenisKelamin,Usia)

Simple Random Sampling

set.seed(123)

sample_simple <- data_mahasiswa[sample(1:100, 20), ]

sample_simple
##    No               Nama JenisKelamin Usia
## 31 31        Ghina Oamra    Perempuan   31
## 79 79    Syahmina Dairah    Perempuan   33
## 51 51       Laziz Luzman    Laki-laki   24
## 14 14      Diyanah Sakhi    Perempuan   30
## 67 67       Qafiya Finna    Perempuan   33
## 42 42      Kalifa Kayesa    Perempuan   27
## 50 50      Latif Ma’arif    Laki-laki   33
## 43 43         Kanz Nabih    Laki-laki   32
## 97 97 Xaquille Atthallah    Laki-laki   27
## 25 25    Fildzhah Qamira    Perempuan   30
## 90 90    Varisha Athifah    Perempuan   30
## 69 69      Qarirah Fayza    Perempuan   27
## 57 57     Mazaya Hazimah    Perempuan   33
## 9   9    Bari’ah Unaisah    Perempuan   30
## 72 72     Rahadatu Ezzah    Perempuan   29
## 26 26       Gamya Saabiq    Laki-laki   27
## 7   7     Arrazi Yaqdhan    Laki-laki   32
## 95 95        Wail Bashra    Laki-laki   30
## 87 87      Uqbah Daniyal    Laki-laki   25
## 36 36   Hanania Nadhirah    Perempuan   25

Artinya 20 mahasiswa dipilih secara acak dari 100 mahasiswa.

Systematic Random Sampling

k <- 5
start <- sample(1:k,1)

sample_systematic <- data_mahasiswa[seq(start,100,by=k),]

sample_systematic
##    No             Nama JenisKelamin Usia
## 1   1   Aatirah Zuyyin    Perempuan   29
## 6   6  Arfathan Yassar    Laki-laki   25
## 11 11 Cordelia Tahsina    Perempuan   30
## 16 16  Dzakwaan Ukasya    Laki-laki   26
## 21 21    Fadhal Taamir    Laki-laki   25
## 26 26     Gamya Saabiq    Laki-laki   27
## 31 31      Ghina Oamra    Perempuan   31
## 36 36 Hanania Nadhirah    Perempuan   25
## 41 41      Jajmi Omran    Laki-laki   24
## 46 46  Khansa Juhairah    Perempuan   28
## 51 51     Laziz Luzman    Laki-laki   24
## 56 56 Manaf kemenangan    Laki-laki   31
## 61 61     Nahdan Kalil    Laki-laki   32
## 66 66    Qabil Hibrizi    Laki-laki   31
## 71 71     Raeef Gulzar    Laki-laki   27
## 76 76    Sakhi Diyanah    Perempuan   33
## 81 81    Tamima Chayra    Perempuan   27
## 86 86    Ulwan Dilawar    Laki-laki   31
## 91 91  Varten Bilfaqih    Laki-laki   33
## 96 96     Wasima Afnan    Perempuan   29

Artinya setiap mahasiswa ke-5 dipilih sebagai sampel.

Stratified Random Sampling

(Strata berdasarkan Jenis Kelamin)

library(dplyr)
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
sample_stratified <- data_mahasiswa %>%
group_by(JenisKelamin) %>%
sample_n(10)

sample_stratified
## # A tibble: 20 × 4
## # Groups:   JenisKelamin [2]
##       No Nama             JenisKelamin  Usia
##    <int> <chr>            <chr>        <dbl>
##  1    82 Tanvir Esad      Laki-laki       24
##  2    71 Raeef Gulzar     Laki-laki       27
##  3    98 Yafizhan Asraf   Laki-laki       31
##  4    21 Fadhal Taamir    Laki-laki       25
##  5    26 Gamya Saabiq     Laki-laki       27
##  6    58 Naayif Kaysan    Laki-laki       31
##  7    78 Shakhar Fahd     Laki-laki       24
##  8    85 Udayl Efendy     Laki-laki       29
##  9    16 Dzakwaan Ukasya  Laki-laki       26
## 10    18 Emyr Tasadduq    Laki-laki       26
## 11    88 Utsratun Bahiyya Perempuan       25
## 12    24 Fathinah Qismina Perempuan       30
## 13    48 Laila Jameela    Perempuan       28
## 14    60 Naflah Halwa     Perempuan       32
## 15    10 Busyra Tsabitah  Perempuan       28
## 16    90 Varisha Athifah  Perempuan       30
## 17    69 Qarirah Fayza    Perempuan       27
## 18    80 Talita Chayra    Perempuan       28
## 19    55 Malihah Ibnatu   Perempuan       27
## 20    74 Ramizah Erina    Perempuan       28

Artinya masing-masing gender diambil sampel 10 mahasiswa.

Cluster Random Sampling

data_mahasiswa$cluster <- ceiling(data_mahasiswa$No/20)

unique(data_mahasiswa$cluster)
## [1] 1 2 3 4 5
cluster_terpilih <- sample(unique(data_mahasiswa$cluster),1)

sample_cluster <- data_mahasiswa[data_mahasiswa$cluster == cluster_terpilih,]

sample_cluster
##      No                Nama JenisKelamin Usia cluster
## 81   81       Tamima Chayra    Perempuan   27       5
## 82   82         Tanvir Esad    Laki-laki   24       5
## 83   83       Tasadduq Emyr    Laki-laki   26       5
## 84   84 Thafana Chairunnisa    Perempuan   24       5
## 85   85        Udayl Efendy    Laki-laki   29       5
## 86   86       Ulwan Dilawar    Laki-laki   31       5
## 87   87       Uqbah Daniyal    Laki-laki   25       5
## 88   88    Utsratun Bahiyya    Perempuan   25       5
## 89   89         Uwais Carim    Laki-laki   29       5
## 90   90     Varisha Athifah    Perempuan   30       5
## 91   91     Varten Bilfaqih    Laki-laki   33       5
## 92   92         Velid bijak    Laki-laki   26       5
## 93   93        Wafiyya Aniq    Perempuan   33       5
## 94   94     Wafiyyati Aliza    Perempuan   27       5
## 95   95         Wail Bashra    Laki-laki   30       5
## 96   96        Wasima Afnan    Perempuan   29       5
## 97   97  Xaquille Atthallah    Laki-laki   27       5
## 98   98      Yafizhan Asraf    Laki-laki   31       5
## 99   99        Yang Arsalan    Laki-laki   24       5
## 100 100     Yassar Arfathan    Laki-laki   32       5

Artinya 1 kelompok mahasiswa dipilih sebagai sampel.

mean(sample_simple$Usia)
## [1] 29.4
mean(sample_systematic$Usia)
## [1] 28.4
mean(sample_stratified$Usia)
## [1] 27.65
mean(sample_cluster$Usia)
## [1] 28.1