Tugas Pertemuan 4

# Data awal
data <- c(22, 25, 19, 30, 24, 21, 45, 23, 20, 26, 24, 22, 18, 27, 23)

# Soal Nomor 1
mean_val <- mean(data)
median_val <- median(data)

get_mode <- function(v) {
   uniqv <- unique(v)
   freq <- tabulate(match(v, uniqv))
   uniqv[freq == max(freq)]
}
mode_val <- get_mode(data)

# Tampilkan Hasil Langsung
mean_val

## [1] 24.6

median_val

## [1] 23

mode_val

## [1] 22 24 23

# Soal Nomor 2
# Menghitung Kuartil dengan type = 6 (Sesuai rumus posisi manual (n+1)*p)
q1 <- quantile(data, 0.25, type = 6)
q3 <- quantile(data, 0.75, type = 6)
iqr_val <- q3 - q1

# Tampilkan Hasil Langsung
q1

## 25% 
##  21

q3

## 75% 
##  26

iqr_val

## 75% 
##   5

# Soal Nomor 3
var_val <- var(data)
sd_val <- sd(data)

# Tampilkan Hasil Langsung
var_val

## [1] 41.54286

sd_val

## [1] 6.445375

# Soal Nomor 4
# 1. Pearson Skewness (Manual Formula di R)
skew_pearson <- 3 * (mean_val - median_val) / sd_val

# 2. Skewness menggunakan package 'moments'
library(moments)
skew_moments <- skewness(data)

# Tampilkan Hasil Langsung
skew_pearson

## [1] 0.7447201

skew_moments

## [1] 2.212573