options(scipen = 999) library(dplyr) library(car) library(lmtest) library(stargazer) library(sandwich) library(lmtest) setwd("C:/Users/irina/Documents/DND/EOHI/eohi1") df <- read.csv("ehi1.csv") data <- df %>% select(eohiDGEN_mean, ehi_global_mean, demo_sex, demo_age_1) %>% filter(demo_sex != "Prefer not to say") str(data) colSums(is.na(data)) sapply(data, class) # Create dummy variable for sex (0 = Male, 1 = Female) data$sex_dummy <- ifelse(data$demo_sex == "Female", 1, 0) # Verify the dummy coding print(table(data$demo_sex, data$sex_dummy))