A2 Markdown

library(readxl)
library(ggplot2)


DatasetA2 <- read_excel("C:/Users/Admin/Downloads/DatasetA2.xlsx")

table(DatasetA2$FavoriteDrink)

## 
## Coffee   Soda    Tea  Water 
##     26     29     28     17

ggplot(DatasetA2, aes(x = FavoriteDrink, fill = FavoriteDrink)) +
  geom_bar() +
  labs(
    x = "FavoriteDrink",
    y = "Frequency",
    title = "Distribution of FavoriteDrink"
  ) +
  theme(
    text = element_text(size = 14),       
    axis.title = element_text(size = 14),  
    axis.text = element_text(size = 14),  
    plot.title = element_text(size = 14),  
    legend.position = "none"              
  )  

observed <- c(26, 29, 28, 17) 
expected <- c(0.25, 0.25, 0.25, 0.25)
chisq.test(x = observed, p = expected)

## 
##  Chi-squared test for given probabilities
## 
## data:  observed
## X-squared = 3.6, df = 3, p-value = 0.308

# A chi-square goodness-of-fit test indicated that the observed frequencies were not significantly different from the expected frequencies, χ²(2) = 3.6, p = .308. Hence, the Cohen's W (Effect Size) was not calculated.