t-test-animation.R

library(magick)
library(purrr)
library(ggplot2)

# Define variables
FRAMES <- 30
MEAN1 <- 0  # Mean of the first group
MEAN2 <- 0.2  # Mean of the second group
FROM <- 2
TO <- 1500

set.seed(1)

images_list <- seq(FROM, TO, length.out = FRAMES) |>
  map(\(n) {
    n  <- as.integer(n)    
    data1 <- rnorm(n, mean = MEAN1, sd = 1)
    data2 <- rnorm(n, mean = MEAN2, sd = 1)
    t_test <- t.test(data1, data2)
    p_value <- t_test$p.value
    plot_data <- data.frame(
      value = c(data1, data2),
      group = factor(rep(c("Normal(0, 1)", "Normal(0.2, 1)"), each = n))
    )

    img <- image_graph(600, 400, res = 96)
    plot <- ggplot(plot_data, aes(x = value, fill = group)) +
      geom_density(alpha = 0.3) +
      labs(
        title = "Comparison of Means",
        subtitle = paste0("T-test p-value: ", round(p_value, 4), " (n = ", n, ")"),
        x = "Value",
        y = "Density",
        fill = ""
      ) +
      scale_fill_manual(values = c("blue", "red")) +
      theme_bw() +
      theme(legend.position = "top") 
    print(plot)
    dev.off()
    img
  })
animation <- image_animate(image_join(images_list), delay = 200, optimize = TRUE, loop = 0)
print(animation)
image_write(animation, "T_Test_Comparison.gif")