Question

# Data were obtained on the reduction in cholesterol count (in mg per 100 ml of blood

serum) for a sample of

15 male subject participating in a study to test if a lowcholesterol

diet reduces serum cholesterol. Each subject participated in the study

for four weeks. The response variable was the reduction in cholesterol. It was also

anticipated that the reduction in cholesterol might depend on the subject’s age. You

can cut and paste the data into R. In case you have dicuy cutting from this pdf le

I also put the data into a text le on SmartSite

x=c(45,43,46,49,50,37,34,30,31,26,22,58,60,52,27)

y=c(30,52,45,38,62,55,25,30,40,17,27,44,61,58,45)

(a) Make a scatter plot of the data. Don’t print the graph until you have added the

regression line (part e).

(b) Calculate the slope of the regression line.

(c) Calculate the intercept of the regression line.

d) Add the regression line to the scatter plot and turn in the graph with your homework.

We add the line by calculating the predicted values of y at the minimum

value of x (which is 22) and the maximum value of x (which is 60).

Statistics and Probability