Komputasi Stat Kelas

# Membuat data sumbu x
x <- seq(-4, 4, by = 0.01)

# Menghitung nilai fungsi densitas normal
y <- dnorm(x, mean = 0, sd = 1)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi Normal Standar",
     xlab = "Nilai X",
     ylab = "Densitas")
grid()

# Parameter distribusi
mu <- 10
varians <- 2
sigma <- sqrt(varians)

# Membuat data sumbu x
x <- seq(mu - 4*sigma, mu + 4*sigma, by = 0.01)

# Menghitung nilai densitas normal
y <- dnorm(x, mean = mu, sd = sigma)

# Membuat kurva distribusi normal
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi Normal",
     xlab = "X",
     ylab = "Densitas")

# Menambahkan garis rata-rata
abline(v = mu,
       col = "red",
       lty = 2,
       lwd = 2)

grid()

# Parameter pertama
mu1 <- 10
varians1 <- 2
sigma1 <- sqrt(varians1)

# Parameter kedua
mu2 <- 12
varians2 <- 2
sigma2 <- sqrt(varians2)

# Sumbu x
x <- seq(2, 20, by = 0.01)

# Kurva pertama
plot(x,
     dnorm(x, mean = mu1, sd = sigma1),
     type = "l",
     lwd = 2,
     col = "blue",
     ylim = c(0, 0.30),
     main = "Kurva Distribusi Normal Bertumpuk",
     xlab = "Nilai X",
     ylab = "Densitas")

# Kurva kedua (bertumpuk)
lines(x,
      dnorm(x, mean = mu2, sd = sigma2),
      col = "red",
      lwd = 2)

# Garis rata-rata
abline(v = mu1, col = "blue", lty = 2)
abline(v = mu2, col = "red", lty = 2)

# Legenda
legend("topright",
       legend = c(expression(mu==10~","~sigma^2==2),
                  expression(mu==12~","~sigma^2==2)),
       col = c("blue", "red"),
       lwd = 2,
       lty = 1)

grid()

# Membuat data sumbu x
x <- seq(-4, 4, by = 0.01)

# Menghitung nilai fungsi densitas normal
y <- dnorm(x, mean = 2, sd = 1)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi Normal Standar",
     xlab = "Nilai X",
     ylab = "Densitas")
grid()

# Membuat data sumbu x
x <- seq(-4, 4, by = 0.01)

# Menghitung nilai fungsi densitas normal
y <- dnorm(x, mean = 5, sd = 5)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi Normal Standar",
     xlab = "Nilai X",
     ylab = "Densitas")
grid()

# Membuat data sumbu x
x <- seq(-4, 4, by = 0.01)

# Menghitung nilai fungsi densitas normal
y <- dnorm(x, mean = 10, sd = 3)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi Normal Standar",
     xlab = "Nilai X",
     ylab = "Densitas")
grid()

# Membuat data sumbu x
x <- seq(-4, 4, by = 0.01)

# Menghitung nilai fungsi densitas normal
y <- dnorm(x, mean = 0.1, sd = 0.1)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi Normal Standar",
     xlab = "Nilai X",
     ylab = "Densitas")
grid()

# Kurva/Garvik 1
curve(dnorm(x, mean = 0, sd = 1),
      from = -5, to = 15,
      col = "purple",
      lwd = 2,
      main = "Simulasi Distribusi Normal",
      xlab = "Nilai X",
      ylab = "Densitas")

# Kurva/Garvik 2
curve(dnorm(x, mean = 2, sd = 1),
      from = -5, to = 15,
      col = "blue",
      lwd = 2,
      add = TRUE)

# Kurva/Garvik 3
curve(dnorm(x, mean = 5, sd = 5),
      from = -5, to = 15,
      col = "red",
      lwd = 2,
      add = TRUE)

# Kurva/Garvik 4
curve(dnorm(x, mean = 10, sd = 3),
      from = -5, to = 15,
      col = "green",
      lwd = 2,
      add = TRUE)

# Kurva/Garvik 5
curve(dnorm(x, mean = 1.5, sd = 0.1),
      from = -5, to = 15,
      col = "orange",
      lwd = 2,
      add = TRUE)

# Keterangan
legend("topright",
       legend = c("μ=0, σ=1",
                  "μ=2, σ=1",
                  "μ=5, σ=5",
                  "μ=10, σ=3",
                  "μ=1.5, σ=0.1"),
       col = c("purple", "blue", "red", "green", "orange"),
       lwd = 2)

# 1. Plot kurva pertama sebagai dasar grafik (mengatur rentang sumbu x dan y)
curve(dnorm(x, mean = 0, sd = 1), from = -10, to = 22, ylim = c(0, 4),
      col = "blue", lwd = 2, 
      main = "Perbandingan 5 Kurva Distribusi Normal", 
      xlab = "Nilai X", ylab = "Densitas")

# 2. Tambahkan kurva 2 sampai 5
curve(dnorm(x, mean = 2, sd = 1), add = TRUE, col = "red", lwd = 2)
curve(dnorm(x, mean = 5, sd = 5), add = TRUE, col = "green", lwd = 2)
curve(dnorm(x, mean = 10, sd = 3), add = TRUE, col = "purple", lwd = 2)
curve(dnorm(x, mean = 1.5, sd = 0.1), add = TRUE, col = "orange", lwd = 2)

# 3. Legenda
legend("topright", 
       legend = c("Kurva 1 (Mu=0, SD=1)", 
                  "Kurva 2 (Mu=2, SD=1)", 
                  "Kurva 3 (Mu=5, SD=5)", 
                  "Kurva 4 (Mu=10, SD=3)", 
                  "Kurva 5 (Mu=1.5, SD=0.1)"), 
       col = c("blue", "red", "green", "purple", "orange"), 
       lwd = 2, cex = 0.8)

# Parameter
df <- 10

# Membuat data sumbu x
x <- seq(-5, 5, by = 0.01)

# Menghitung densitas distribusi t
y <- dt(x, df = df)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "blue",
     main = "Kurva Distribusi t",
     xlab = "Nilai t",
     ylab = "Densitas")

abline(v = 0, lty = 2)
grid()

# Parameter
df <- 5

# Membuat data sumbu x
x <- seq(0, 25, by = 0.01)

# Menghitung densitas Chi-Square
y <- dchisq(x, df = df)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "red",
     main = "Kurva Distribusi Chi-Square",
     xlab = expression(chi^2),
     ylab = "Densitas")

grid()

# Parameter
df1 <- 5
df2 <- 10

# Membuat data sumbu x
x <- seq(0, 5, by = 0.01)

# Menghitung densitas distribusi F
y <- df(x, df1 = df1, df2 = df2)

# Membuat grafik
plot(x, y,
     type = "l",
     lwd = 2,
     col = "darkgreen",
     main = "Kurva Distribusi F",
     xlab = "Nilai F",
     ylab = "Densitas")

grid()