# Question

A clinical trial admits subjects suffering from high cholesterol, who are then randomly assigned to take a drug or a placebo for a 12-week study. For the population, without taking any drug, the correlation between the cholesterol readings at times 12 weeks apart is 0.70. The mean cholesterol reading at any given time is 200, with the same standard deviation at each time. Consider all the subjects with a cholesterol level of 300 at the start of the study, who take placebo.

a. What would you predict for their mean cholesterol level at the end of the study?

b. Does this suggest that placebo is effective for treating high cholesterol? Explain.

a. What would you predict for their mean cholesterol level at the end of the study?

b. Does this suggest that placebo is effective for treating high cholesterol? Explain.

## Answer to relevant Questions

For a class of 100 students, the teacher takes the 10 students who performed poorest on the midterm exam and enrolls them in a special tutoring program. Both the midterm and final have a class mean of 70 with standard ...Use software to analyze the U.S. Statewide Crime data file on the text CD on y = violent crime rate and x = percentage of single parent families. a. Construct a scatter-plot. What does it show? b. One point is quite far ...Repeat the previous exercise using x = number of daughters the woman had, for which the slope estimate was 0.44 (se = 0.29). Previous exercise a. Interpret the sign of the slope. Is the effect of having more boys good, or ...For the Georgia Student Survey file on the text CD, let y = exercise and x = watch TV. One student reported watching TV an average of 180 minutes a day and exercising 60 minutes a day. This person’s residual was 48.8 and ...For prediction intervals, an important inference assumption is a constant residual standard deviation of y values at different x values. In practice, the residual standard deviation often tends to be larger when μy is ...Post your question

0