distribusi normal

# Parameter distribusi normal
mu <- 10      # Rata-rata (mean)
sigma <- 2   # Standar deviasi (sd)

# Membuat kurva distribusi normal
curve(dnorm(x, mean = mu, sd = sigma), 
      from = -4, to = 4, 
      col = "navy", 
      lwd = 2,
      main = "Kurva Distribusi Normal Standar",
      xlab = "Nilai X (Z-score)", 
      ylab = "Kerapatan (Density)")

# Menambahkan garis vertikal di titik rata-rata (mean)
abline(v = mu, col = "red", lty = 2, lwd = 1.5)

# Load library
library(ggplot2)

# Data parameter dari tabel pada gambar
data_simulasi <- data.frame(
  No = 1:5,
  mu = c(0, 2, 5, 10, 1.5),
  sd = c(1, 1, 5, 3, 0.1),
  Label = c("1: mu=0, sd=1", 
            "2: mu=2, sd=1", 
            "3: mu=5, sd=5", 
            "4: mu=10, sd=3", 
            "5: mu=1.5, sd=0.1")
)

# Menentukan rentang sumbu-X yang mencakup seluruh distribusi
x_min <- -10
x_max <- 25

# Membuat plot kurva distribusi normal
p <- ggplot(data.frame(x = c(x_min, x_max)), aes(x = x)) +
  # Kurva 1
  stat_function(fun = dnorm, args = list(mean = 0, sd = 1), 
                aes(color = "1: mu=0, sd=1"), linewidth = 1) +
  # Kurva 2
  stat_function(fun = dnorm, args = list(mean = 2, sd = 1), 
                aes(color = "2: mu=2, sd=1"), linewidth = 1) +
  # Kurva 3
  stat_function(fun = dnorm, args = list(mean = 5, sd = 5), 
                aes(color = "3: mu=5, sd=5"), linewidth = 1) +
  # Kurva 4
  stat_function(fun = dnorm, args = list(mean = 10, sd = 3), 
                aes(color = "4: mu=10, sd=3"), linewidth = 1) +
  # Kurva 5
  stat_function(fun = dnorm, args = list(mean = 1.5, sd = 0.1), 
                aes(color = "5: mu=1.5, sd=0.1"), linewidth = 1) +
  # Pengaturan Warna Kurva
  scale_color_manual(
    name = "Simulasi Normal",
    values = c(
      "1: mu=0, sd=1"    = "#1F77B4",  # Biru
      "2: mu=2, sd=1"    = "#FF7F0E",  # Oranye
      "3: mu=5, sd=5"    = "#2CA02C",  # Hijau
      "4: mu=10, sd=3"   = "#D62728",  # Merah
      "5: mu=1.5, sd=0.1"= "#9467BD"   # Ungu
    )
  ) +
  # Judul & Label Sumbu
  labs(
    title = "Simulasi Distribusi Normal",
    subtitle = "Perbandingan 5 Kurva dengan Rata-rata (mu) dan Simpangan Baku (sd) Berbeda",
    x = "Nilai X",
    y = "Kerapatan (Density)"
  ) +
  theme_minimal() +
  theme(
    plot.title = element_text(face = "bold", size = 14),
    legend.position = "right"
  )

# Tampilkan grafik
print(p)