#TM 4 Komputasi Statistika
#PACKAGES
library(car)
## Warning: package 'car' was built under R version 4.5.3
## Loading required package: carData
## Warning: package 'carData' was built under R version 4.5.3
library(agricolae)
## Warning: package 'agricolae' was built under R version 4.5.3
#Memanggil Data
data=read.table(file.choose(), header=T, dec = ",")
data
##   tablet pelarut  Data
## 1      1       1 46.18
## 2      1       2 54.54
## 3      1       3 56.63
## 4      2       1 57.69
## 5      2       2 71.57
## 6      2       3 81.51
## 7      3       1 48.61
## 8      3       2 51.01
## 9      3       3 80.02
#Pendefinisian Variabel
data$tablet=factor(data$tablet,levels=1:3,labels=c("CDR","Redoxon","Enervon-C"))
data$pelarut=factor(data$pelarut,levels=1:3,labels=c("Air Biasa","Air Soda","Air kelapa"))
data
##      tablet    pelarut  Data
## 1       CDR  Air Biasa 46.18
## 2       CDR   Air Soda 54.54
## 3       CDR Air kelapa 56.63
## 4   Redoxon  Air Biasa 57.69
## 5   Redoxon   Air Soda 71.57
## 6   Redoxon Air kelapa 81.51
## 7 Enervon-C  Air Biasa 48.61
## 8 Enervon-C   Air Soda 51.01
## 9 Enervon-C Air kelapa 80.02
#Normalitas per Jenis Pelarut
for(j in levels(data$pelarut)){
  cat("\nUji Normalitas untuk Jenis Pelarut:", j, "\n")
  print(shapiro.test(data$Data[data$pelarut==j]))
}
## 
## Uji Normalitas untuk Jenis Pelarut: Air Biasa 
## 
##  Shapiro-Wilk normality test
## 
## data:  data$Data[data$pelarut == j]
## W = 0.89987, p-value = 0.3851
## 
## 
## Uji Normalitas untuk Jenis Pelarut: Air Soda 
## 
##  Shapiro-Wilk normality test
## 
## data:  data$Data[data$pelarut == j]
## W = 0.87434, p-value = 0.3079
## 
## 
## Uji Normalitas untuk Jenis Pelarut: Air kelapa 
## 
##  Shapiro-Wilk normality test
## 
## data:  data$Data[data$pelarut == j]
## W = 0.79474, p-value = 0.102
# Normalitas per Merek Tablet
for(i in levels(data$tablet)){
  cat("\nUji Normalitas untuk Merek Tablet:", i, "\n")
  print(shapiro.test(data$Data[data$tablet==i]))
}
## 
## Uji Normalitas untuk Merek Tablet: CDR 
## 
##  Shapiro-Wilk normality test
## 
## data:  data$Data[data$tablet == i]
## W = 0.89286, p-value = 0.3631
## 
## 
## Uji Normalitas untuk Merek Tablet: Redoxon 
## 
##  Shapiro-Wilk normality test
## 
## data:  data$Data[data$tablet == i]
## W = 0.99096, p-value = 0.8182
## 
## 
## Uji Normalitas untuk Merek Tablet: Enervon-C 
## 
##  Shapiro-Wilk normality test
## 
## data:  data$Data[data$tablet == i]
## W = 0.80695, p-value = 0.1312
#Homogenitas variansi
leveneTest(Data~pelarut, center=mean, data=data)
## Levene's Test for Homogeneity of Variance (center = mean)
##       Df F value Pr(>F)
## group  2  1.9806 0.2185
##        6
leveneTest(Data~tablet, center=mean, data=data)
## Levene's Test for Homogeneity of Variance (center = mean)
##       Df F value Pr(>F)
## group  2  2.4902 0.1632
##        6
#Uji ANOVA
anava2arah <- function(y, A, B){
  a <- nlevels(A); b <- nlevels(B)
  N <- length(y); n <- N/(a*b)
  
  FK    <- sum(y)^2/N
  JKT   <- sum(y^2) - FK
  JK_A  <- sum(tapply(y, A, sum)^2)/(b*n) - FK
  JK_B  <- sum(tapply(y, B, sum)^2)/(a*n) - FK
  JKsel <- sum(tapply(y, list(A,B), sum)^2)/n - FK
  JK_AB <- JKsel - JK_A - JK_B
  JKG   <- JKT - JKsel
  db  <- c(a-1, b-1, (a-1)*(b-1), a*b*(n-1), N-1)
  JK  <- c(JK_A, JK_B, JK_AB, JKG, JKT)
  KT  <- JK/db
  F   <- c(KT[1:2]/KT[3], NA, NA, NA)
  p   <- c(pf(F[1:2], db[1:2], db[3], lower.tail=FALSE), NA, NA, NA)
  
  data.frame(Sumber=c("Tablet","Pelarut","Tablet*Pelarut","Galat","Total"), db=db, JK=JK, KT=KT, F_hitung=F, p_value=p)
}
anava2arah(y=data$Data, A=data$tablet, B=data$pelarut)
##           Sumber db        JK        KT F_hitung    p_value
## 1         Tablet  2  479.9575 239.97874 4.269572 0.10176166
## 2        Pelarut  2  733.9193 366.95964 6.528748 0.05499073
## 3 Tablet*Pelarut  4  224.8270  56.20674       NA         NA
## 4          Galat  0    0.0000       NaN       NA         NA
## 5          Total  8 1438.7038 179.83797       NA         NA
uji_anava=aov(Data~tablet+pelarut,data=data)
anova(uji_anava)
## Analysis of Variance Table
## 
## Response: Data
##           Df Sum Sq Mean Sq F value  Pr(>F)  
## tablet     2 479.96  239.98  4.2696 0.10176  
## pelarut    2 733.92  366.96  6.5287 0.05499 .
## Residuals  4 224.83   56.21                  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1