data <- matrix(scan(),ncol=4,byrow=TRUE) 1 1 4 15.5 1 2 2 33.9 1 3 3 13.2 1 4 1 29.1 2 1 2 16.3 2 2 3 26.6 2 3 1 19.4 2 4 4 22.8 3 1 3 10.8 3 2 1 31.1 3 3 4 17.1 3 4 2 30.3 4 1 1 14.7 4 2 4 34. 4 3 2 19.7 4 4 3 21.6 data Gas1 <- data.frame(data) colnames(Gas1) <- c("driver","car","gas","mileage") Gas1$driver <- as.factor(Gas1$driver) # to make sure that driver is a factor, not numeric Gas1$gas <- as.factor(Gas1$gas) # to make sure that gas is a factor, not numeric Gas1$car <- as.factor(Gas1$car) # to make sure that car is a factor, not numeric rm(data) Gas1 summary(lm(mileage ~ driver + car + gas, data = Gas1)) anova(lm(mileage ~ driver + car + gas, data = Gas1)) par(mfrow=c(2,2)) plot(lm(mileage ~ driver + car + gas, data = Gas1)) par(mfrow=c(1,1)) rm(Gas1)