CODE 6 : MTCAR DATA

CODE 6 : MTCAR  DATA

1.cars_data <- mtcars
  mean : a regression model with more than 1 independent variable
              and we need to create a dataset by use the data of mtcars

2.cars_data$log_mpg <- log(cars_data$mpg)
  cars_data$log_hp <- log(cars_data$hp)
   model1 <- lm(log_mg ~ log_hp ~ data= cars_data)
   summary(model1)

   mean : to satisfy the regression assumption, transform the mpg and hp
               by take log because the skewness of mpg and hp is positive

              and finally made summary in model 1

3.cor(car_data)
 mean : The relationship between the data in the car_data.

4.cor(car_data$hp, car_data$am)
mean : The relationship between the data hp with information that is relevant am or not .

5.hist(cars_data$am)
mean : made a histogram of car data as am

SECTION 2 :

 1.library(psych)
    describe(cars_data$am)
 mean : call package psych to describe cars_data$am

2. model 2 <- lm(log_mg ~ log_hp + am, data =cars_data)
    summary(model 2)
 
    anova( model 1, model 2)

mean : to check if the model 2 is statistically better than model 1