Analisis Data Ecotrack

# ==========================================
# INPUT DATA AWAL 'ECOTRACK'
# ==========================================
menit <- c(22, 25, 19, 30, 24, 21, 45, 23, 20, 26, 24, 22, 18, 27, 23)

# ==========================================
# VERIFIKASI NOMOR 1: MEAN, MEDIAN, MODUS
# ==========================================
# Hitung Mean (Rata-rata)
mean(menit)

## [1] 24.6

# Hitung Median (Nilai Tengah)
median(menit)

## [1] 23

# Membuat fungsi khusus modus (karena R tidak punya fungsi bawaan, sesuai slide 8)
modus <- function(x) {
  u <- unique(x)
  tab <- tabulate(match(x, u))
  u[tab == max(tab)]
}
modus(menit)

## [1] 22 24 23

# ==========================================
# VERIFIKASI NOMOR 2: KUARTIL & IQR
# ==========================================
# Menghitung Q1 dan Q3 menggunakan type = 6 (rumus posisi manual sesuai slide 18)
quantile(menit, probs = c(0.25, 0.75), type = 6)

## 25% 75% 
##  21  26

# Menghitung Interquartile Range (IQR)
IQR(menit, type = 6)

## [1] 5

# ==========================================
# VERIFIKASI NOMOR 3: VARIANS & SD SAMPEL
# ==========================================
# Menghitung Varians Sampel
var(menit)

## [1] 41.54286

# Menghitung Standar Deviasi Sampel
sd(menit)

## [1] 6.445375

# ==========================================
# VERIFIKASI NOMOR 4: SKEWNESS (KEMENCENGAN)
# ==========================================
# Aktifkan package 'moments' terlebih dahulu (sesuai slide 26)
# Catatan: jalankan install.packages("moments") jika package belum terpasang
library(moments)

# Menghitung nilai skewness berbasis software
skewness(menit)

## [1] 2.212573