Modul 1

1.1 Deskripsi Singkat

Penyelidikan ilmiah merupakan proses belajar berulang yang bertujuan untuk memperoleh penjelasan atas suatu fenomena melalui eksperimen atau observasi. Selama proses pembelajaran berulang ini, variabel sering ditambahkan atau dihapus dari pembelajaran.
Dengan demikian, kompleksitas sebagian besar fenomena memerlukan peneliti untuk mengumpulkan pengamatan pada banyak variabel berbeda, sehingga untuk itulah kita butuh analisis peubah ganda.
Dalam melakukan analisis peubah ganda kita harus memahami aspek-aspek di dalam analisis peubah ganda terlebih dahulu.

1.2 Tujuan Praktikum

Tujuan pembelajaran pada modul 1 ini adalah memberikan pengetahuan tentang aspek aspek dalam analisis peubah ganda dan mampu melakukan analisis deksriptif dan visualisasi pada data multivariat.

1.3 Material Praktikum

Pada kegiatan modul 1 diperlukan beberapa material berupa software, yaitu:
1) Software R (direkomendasikan versi terbaru).
2) Software R Studio.

1.4 Kegiatan Praktikum

Cobalah Sintaksis R berikut:
Notes : “Gunakan tombol kecil di pojok kanan atas jendela kode untuk menyalin semua sintaks.”

#DATA ORGANIZATION 
 attach(mtcars) 
 #save as matrice 
 dat1 <- as.matrix(mtcars) 
 nrow(dat1) 
 ncol(dat1) 
 dim(dat1) 
 
 #save as dataframe 
 dat2 <- as.data.frame(mtcars) 
 str(dat2) 
 colfac <- c("vs","am","gear","carb") 
 dat2[colfac] <- lapply(dat2[colfac], factor) 
 str(dat2) 
  
#STATISTIK DESKRIPTIF 
 summary(dat2) 
  
 colnum <- c("mpg","cyl","disp","hp","drat","wt","qsec") 
 dat3 <- dat2[colnum] 
  
 apply(dat3,2,mean) 
 apply(dat3,2,var) 
 apply(dat3,2,sd) 
 apply(dat3,2,min) 
 apply(dat3,2,max) 
  
 matkov <- cov(dat3) 
 matkov 
  
##VISUALISASI DATA MULTIVARIAT 
#Scatterplot 
 head(mtcars) 
 plot(wt,mpg) 
#matrix scatterplot 
 plot(mtcars[,c(1,3,4,6)]) 
  
#Scatterplot using ggplot 
 plot1 <- ggplot(mtcars, aes(x=wt, y=mpg)) +  geom_point() + 
 theme(legend.position="none") 
 plot1 
  
#Matrix scatterplot using ggplot 
 library(GGally) 
 plot2 <- ggpairs(mtcars[,c(1,3,4,6)]) 
 plot2 
#Scatterplot dengan marginal 
# library 
library(ggplot2) 
library(ggExtra) 
# The mtcars dataset is proposed in R 
head(mtcars)
# classic plot : 
p <- ggplot(mtcars, aes(x=wt, y=mpg, color=cyl)) +  geom_point() + 
 theme(legend.position="none") 
p 
# with marginal histogram 
p1 <- ggMarginal(p, type="histogram") 
p1 
# marginal density 
p2 <- ggMarginal(p, type="density") 
p2 
# marginal boxplot 
p3 <- ggMarginal(p, type="boxplot") 
p3 
#Trivariate scatterplot 
#install.packages("scatterplot3d") 
library(scatterplot3d) 
scatterplot3d(wt,disp,mpg, main="3D Scatterplot",   color = "red") 
scatterplot3d(wt,disp,mpg, main="3D Scatterplot",   highlight.3d = TRUE) 
dat <- data.frame(wt,disp,mpg) 
plot(dat) 
#install.packages("corrplot") 
library(corrplot) 
# We use Motor Trend Data # 
# Correlation Plot # 
M <- cor(mtcars) 
head(M) 
corrplot(M, method = "circle") 
corrplot(M, method = "ellipse") 
corrplot(M, type = "upper") 
#Scatterplot 3d interactive 
library(shiny) 
library(crosstalk) 
library(rgl) 
library(plot3D) 
library(plot3Drgl)
scatter3Drgl(wt,disp,mpg) 
#stars 
## 'Spider' or 'Radar' plot: 
stars(mtcars[1:6, 1:7], locations = c(0, 0), radius = FALSE, 
 key.loc = c(0, 0), main = "Motor Trend Cars", lty = 1,  
 col.lines = rainbow(6)) 
#chernoff faces 
#install.packages("aplpack") 
library(aplpack) 
faces() 
faces(face.type=1) 
faces(rbind(1:3,5:3,3:5,5:7)) 
data(longley) 
faces(longley[1:9,],face.type=0) 
faces(longley[1:9,],face.type=1) 
faces(mtcars[1:20,1:7]) 

1.5 Hasil Praktikum

  • Install paket packages atau library yang dibutuhkan dengan cara :
  • Load library yang dibutuhkan
  • Coba jalankan semua sintaksnya :
    ( penulis melakukan sedikit perubahan dan penyesuaian dari sintaks awal yang ada di soal. Hal ini dilakukan karena pada sintaks di soal terdapat beberapa error saat dijalankan )
## The following object is masked from package:ggplot2:
## 
##     mpg
## [1] 32
## [1] 11
## [1] 32 11
## 'data.frame':    32 obs. of  11 variables:
##  $ mpg : num  21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 ...
##  $ cyl : num  6 6 4 6 8 6 8 4 4 6 ...
##  $ disp: num  160 160 108 258 360 ...
##  $ hp  : num  110 110 93 110 175 105 245 62 95 123 ...
##  $ drat: num  3.9 3.9 3.85 3.08 3.15 2.76 3.21 3.69 3.92 3.92 ...
##  $ wt  : num  2.62 2.88 2.32 3.21 3.44 ...
##  $ qsec: num  16.5 17 18.6 19.4 17 ...
##  $ vs  : num  0 0 1 1 0 1 0 1 1 1 ...
##  $ am  : num  1 1 1 0 0 0 0 0 0 0 ...
##  $ gear: num  4 4 4 3 3 3 3 4 4 4 ...
##  $ carb: num  4 4 1 1 2 1 4 2 2 4 ...
## 'data.frame':    32 obs. of  11 variables:
##  $ mpg : num  21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 ...
##  $ cyl : num  6 6 4 6 8 6 8 4 4 6 ...
##  $ disp: num  160 160 108 258 360 ...
##  $ hp  : num  110 110 93 110 175 105 245 62 95 123 ...
##  $ drat: num  3.9 3.9 3.85 3.08 3.15 2.76 3.21 3.69 3.92 3.92 ...
##  $ wt  : num  2.62 2.88 2.32 3.21 3.44 ...
##  $ qsec: num  16.5 17 18.6 19.4 17 ...
##  $ vs  : Factor w/ 2 levels "0","1": 1 1 2 2 1 2 1 2 2 2 ...
##  $ am  : Factor w/ 2 levels "0","1": 2 2 2 1 1 1 1 1 1 1 ...
##  $ gear: Factor w/ 3 levels "3","4","5": 2 2 2 1 1 1 1 2 2 2 ...
##  $ carb: Factor w/ 6 levels "1","2","3","4",..: 4 4 1 1 2 1 4 2 2 4 ...
##       mpg             cyl             disp             hp       
##  Min.   :10.40   Min.   :4.000   Min.   : 71.1   Min.   : 52.0  
##  1st Qu.:15.43   1st Qu.:4.000   1st Qu.:120.8   1st Qu.: 96.5  
##  Median :19.20   Median :6.000   Median :196.3   Median :123.0  
##  Mean   :20.09   Mean   :6.188   Mean   :230.7   Mean   :146.7  
##  3rd Qu.:22.80   3rd Qu.:8.000   3rd Qu.:326.0   3rd Qu.:180.0  
##  Max.   :33.90   Max.   :8.000   Max.   :472.0   Max.   :335.0  
##       drat             wt             qsec       vs     am     gear   carb  
##  Min.   :2.760   Min.   :1.513   Min.   :14.50   0:18   0:19   3:15   1: 7  
##  1st Qu.:3.080   1st Qu.:2.581   1st Qu.:16.89   1:14   1:13   4:12   2:10  
##  Median :3.695   Median :3.325   Median :17.71                 5: 5   3: 3  
##  Mean   :3.597   Mean   :3.217   Mean   :17.85                        4:10  
##  3rd Qu.:3.920   3rd Qu.:3.610   3rd Qu.:18.90                        6: 1  
##  Max.   :4.930   Max.   :5.424   Max.   :22.90                        8: 1
##        mpg        cyl       disp         hp       drat         wt       qsec 
##  20.090625   6.187500 230.721875 146.687500   3.596563   3.217250  17.848750
##          mpg          cyl         disp           hp         drat           wt 
## 3.632410e+01 3.189516e+00 1.536080e+04 4.700867e+03 2.858814e-01 9.573790e-01 
##         qsec 
## 3.193166e+00
##         mpg         cyl        disp          hp        drat          wt 
##   6.0269481   1.7859216 123.9386938  68.5628685   0.5346787   0.9784574 
##        qsec 
##   1.7869432
##    mpg    cyl   disp     hp   drat     wt   qsec 
## 10.400  4.000 71.100 52.000  2.760  1.513 14.500
##     mpg     cyl    disp      hp    drat      wt    qsec 
##  33.900   8.000 472.000 335.000   4.930   5.424  22.900
##              mpg         cyl        disp         hp         drat          wt
## mpg    36.324103  -9.1723790  -633.09721 -320.73206   2.19506351  -5.1166847
## cyl    -9.172379   3.1895161   199.66028  101.93145  -0.66836694   1.3673710
## disp -633.097208 199.6602823 15360.79983 6721.15867 -47.06401915 107.6842040
## hp   -320.732056 101.9314516  6721.15867 4700.86694 -16.45110887  44.1926613
## drat    2.195064  -0.6683669   -47.06402  -16.45111   0.28588135  -0.3727207
## wt     -5.116685   1.3673710   107.68420   44.19266  -0.37272073   0.9573790
## qsec    4.509149  -1.8868548   -96.05168  -86.77008   0.08714073  -0.3054816
##              qsec
## mpg    4.50914919
## cyl   -1.88685484
## disp -96.05168145
## hp   -86.77008065
## drat   0.08714073
## wt    -0.30548161
## qsec   3.19316613
##                    mpg cyl disp  hp drat    wt  qsec vs am gear carb
## Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
## Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
## Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
## Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
## Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
## Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1

##                    mpg cyl disp  hp drat    wt  qsec vs am gear carb
## Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
## Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
## Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
## Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
## Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
## Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1

##             mpg        cyl       disp         hp       drat         wt
## mpg   1.0000000 -0.8521620 -0.8475514 -0.7761684  0.6811719 -0.8676594
## cyl  -0.8521620  1.0000000  0.9020329  0.8324475 -0.6999381  0.7824958
## disp -0.8475514  0.9020329  1.0000000  0.7909486 -0.7102139  0.8879799
## hp   -0.7761684  0.8324475  0.7909486  1.0000000 -0.4487591  0.6587479
## drat  0.6811719 -0.6999381 -0.7102139 -0.4487591  1.0000000 -0.7124406
## wt   -0.8676594  0.7824958  0.8879799  0.6587479 -0.7124406  1.0000000
##             qsec         vs         am       gear       carb
## mpg   0.41868403  0.6640389  0.5998324  0.4802848 -0.5509251
## cyl  -0.59124207 -0.8108118 -0.5226070 -0.4926866  0.5269883
## disp -0.43369788 -0.7104159 -0.5912270 -0.5555692  0.3949769
## hp   -0.70822339 -0.7230967 -0.2432043 -0.1257043  0.7498125
## drat  0.09120476  0.4402785  0.7127111  0.6996101 -0.0907898
## wt   -0.17471588 -0.5549157 -0.6924953 -0.5832870  0.4276059

## effect of variables:
##  modified item       Var   
##  "height of face   " "Var1"
##  "width of face    " "Var2"
##  "structure of face" "Var3"
##  "height of mouth  " "Var1"
##  "width of mouth   " "Var2"
##  "smiling          " "Var3"
##  "height of eyes   " "Var1"
##  "width of eyes    " "Var2"
##  "height of hair   " "Var3"
##  "width of hair   "  "Var1"
##  "style of hair   "  "Var2"
##  "height of nose  "  "Var3"
##  "width of nose   "  "Var1"
##  "width of ear    "  "Var2"
##  "height of ear   "  "Var3"
## effect of variables:
##  modified item       Var   
##  "height of face   " "Var1"
##  "width of face    " "Var2"
##  "structure of face" "Var3"
##  "height of mouth  " "Var1"
##  "width of mouth   " "Var2"
##  "smiling          " "Var3"
##  "height of eyes   " "Var1"
##  "width of eyes    " "Var2"
##  "height of hair   " "Var3"
##  "width of hair   "  "Var1"
##  "style of hair   "  "Var2"
##  "height of nose  "  "Var3"
##  "width of nose   "  "Var1"
##  "width of ear    "  "Var2"
##  "height of ear   "  "Var3"

## effect of variables:
##  modified item       Var   
##  "height of face   " "Var1"
##  "width of face    " "Var2"
##  "structure of face" "Var3"
##  "height of mouth  " "Var1"
##  "width of mouth   " "Var2"
##  "smiling          " "Var3"
##  "height of eyes   " "Var1"
##  "width of eyes    " "Var2"
##  "height of hair   " "Var3"
##  "width of hair   "  "Var1"
##  "style of hair   "  "Var2"
##  "height of nose  "  "Var3"
##  "width of nose   "  "Var1"
##  "width of ear    "  "Var2"
##  "height of ear   "  "Var3"

## effect of variables:
##  modified item       Var           
##  "height of face   " "GNP.deflator"
##  "width of face    " "GNP"         
##  "structure of face" "Unemployed"  
##  "height of mouth  " "Armed.Forces"
##  "width of mouth   " "Population"  
##  "smiling          " "Year"        
##  "height of eyes   " "Employed"    
##  "width of eyes    " "GNP.deflator"
##  "height of hair   " "GNP"         
##  "width of hair   "  "Unemployed"  
##  "style of hair   "  "Armed.Forces"
##  "height of nose  "  "Population"  
##  "width of nose   "  "Year"        
##  "width of ear    "  "Employed"    
##  "height of ear   "  "GNP.deflator"

## effect of variables:
##  modified item       Var           
##  "height of face   " "GNP.deflator"
##  "width of face    " "GNP"         
##  "structure of face" "Unemployed"  
##  "height of mouth  " "Armed.Forces"
##  "width of mouth   " "Population"  
##  "smiling          " "Year"        
##  "height of eyes   " "Employed"    
##  "width of eyes    " "GNP.deflator"
##  "height of hair   " "GNP"         
##  "width of hair   "  "Unemployed"  
##  "style of hair   "  "Armed.Forces"
##  "height of nose  "  "Population"  
##  "width of nose   "  "Year"        
##  "width of ear    "  "Employed"    
##  "height of ear   "  "GNP.deflator"

## effect of variables:
##  modified item       Var   
##  "height of face   " "mpg" 
##  "width of face    " "cyl" 
##  "structure of face" "disp"
##  "height of mouth  " "hp"  
##  "width of mouth   " "drat"
##  "smiling          " "wt"  
##  "height of eyes   " "qsec"
##  "width of eyes    " "mpg" 
##  "height of hair   " "cyl" 
##  "width of hair   "  "disp"
##  "style of hair   "  "hp"  
##  "height of nose  "  "drat"
##  "width of nose   "  "wt"  
##  "width of ear    "  "qsec"
##  "height of ear   "  "mpg"