You have to use statistical software to answer these questions however, please indicate what software you're using (STATA or Rstudio), and show your work!

Consider the mistudy that you have analyzed in past homework assignments (mistudy.dta file is uploaded). Suppose that we are interested in time to drop-out (i.e., time to censoring) from the study as the event of interest.

(a) (10 points) Is time to drop-out censored in this study? Please explain why or why not, and if so, by what is it censored?

(b) (10 points) Please estimate the distribution of time to drop out, i.e., P(D > t),where D denotes time to drop out. Please include 95% confidence intervals of any type and please identify which type of approximation you are presenting. Please include the code that you used to estimate this.

(c) (10 points) Suppose you want to compare time to drop-out for those who are obese versus those who are not obese. Please display the Kaplan Meier estimates for each group and using a test of your choosing, formally test whether the distributions differ between these groups.

For this question: "Consider the MI study that you have analyzed in past homework assignments.

Suppose that we are interested in time to drop-out (i.e., time to censoring) from the

study as the event of interest.

(a) (10 points) Is time to drop-out censored in this study? Please explain why or why

not, and if so, by what is it censored?"

The drop-out (i.e., censoring) is what is captured in the variable dthtime for those who don't die, it is in the mistudy.dta file.