# TUGAS PENDALAMAN MATERI - ECOTRACK
# 1. MEMASUKKAN DATA
data <- c(22, 25, 19, 30, 24, 21, 45, 23, 20, 26, 24, 22, 18, 27, 23)
# Melihat data
data
## [1] 22 25 19 30 24 21 45 23 20 26 24 22 18 27 23
# Mean
mean(data)
## [1] 24.6
# Median
median(data)
## [1] 23
# Modus
modus <- function(x) {
frekuensi <- table(x)
modus <- names(frekuensi[frekuensi == max(frekuensi)])
as.numeric(modus)
}
modus(data)
## [1] 22 23 24
# 3. Q1, Q3, DAN IQR
# Kuartil
quantile(data, probs = c(0.25, 0.75))
## 25% 75%
## 21.5 25.5
# Q1
Q1 <- quantile(data, 0.25)
# Q3
Q3 <- quantile(data, 0.75)
# IQR
IQR(data)
## [1] 4
Q1
## 25%
## 21.5
Q3
## 75%
## 25.5
IQR(data)
## [1] 4
# 4. VARIANS DAN STANDAR DEVIASI
# Varians sampel
var(data)
## [1] 41.54286
# Standar deviasi sampel
sd(data)
## [1] 6.445375
# Varians populasi (tambahan)
var_populasi <- sum((data - mean(data))^2) / length(data)
var_populasi
## [1] 38.77333
# Standar deviasi populasi
sd_populasi <- sqrt(var_populasi)
sd_populasi
## [1] 6.226824
# 5. SKEWNESS PEARSON
# Koefisien skewness Pearson
skewness_pearson <- 3 * (mean(data) - median(data)) / sd(data)
skewness_pearson
## [1] 0.7447201
# 6. VERIFIKASI SKEWNESS DENGAN R
library(e1071)
# Skewness
skewness(data)
## [1] 1.995046
# 7. RINGKASAN SEMUA HASIL
cat("Mean :", mean(data), "\n")
## Mean : 24.6
cat("Median :", median(data), "\n")
## Median : 23
cat("Modus :", modus(data), "\n")
## Modus : 22 23 24
cat("Q1 :", Q1, "\n")
## Q1 : 21.5
cat("Q3 :", Q3, "\n")
## Q3 : 25.5
cat("IQR :", IQR(data), "\n")
## IQR : 4
cat("Varians :", var(data), "\n")
## Varians : 41.54286
cat("SD :", sd(data), "\n")
## SD : 6.445375
cat("Skewness Pearson :", skewness_pearson, "\n")
## Skewness Pearson : 0.7447201
cat("Skewness e1071 :", skewness(data), "\n")
## Skewness e1071 : 1.995046