library(readxl)
library(ggpubr)
## Loading required package: ggplot2
A5Q1 <- read_excel("C:/Users/sanja/Downloads/A5Q1-1.xlsx")
observed <- table(A5Q1$flavor)
observed
## 
##  Chocolate      Mango Strawberry    Vanilla 
##         87         32         57         74
barplot(observed,
        main = "Flavor preference",
        xlab = "Flavor",
        ylab = "Count",
        col = rainbow(length(observed)))

expected <- c(.20,.20,.20,.40)
chi_result <- chisq.test(x = observed, p = expected)
chi_result
## 
##  Chi-squared test for given probabilities
## 
## data:  observed
## X-squared = 41.6, df = 3, p-value = 4.878e-09
w <- sqrt(as.numeric(chi_result$statistic) / sum(observed))
w
## [1] 0.4079216
# A Chi-Square Goodness of Fit test was conducted to determine if there was a difference between the observed [Flavor preference] frequencies and the expected frequencies.

# The results showed that there [was ] a difference between the observed and expected frequencies, χ²(3) = 41.6, p <.001

The difference was [ moderate ], (Cohen’s W = .40).