BSTA 6652
Take-home Final Exam
Winter 2012
Instruction: This is an exam. You CANNOT discuss the problems with anyone except
the instructor. Breaking this rule is considered as cheating and thus the score of this exam
will be zero. This exam is due on March 21 (Wed) by 6:00 pm. You must submit your
paper to the instructor’s office NS 318 or mailbox in NS 229.
Data:
Multiple myeloma is a malignant disease characterized by the accumulation of abnormal
plasma cells, a type of white blood cell, in the bone marrow. The aim of a study carried
out at the Medical Center of the University of West Virginia was to examine the
association between the values of certain covariates and the survival time of patients.
In this study, the primary response variable was the time, in months, from diagnosis until
death from multiple myeloma. The data file MMA.txt contains the data collected from 48
female patients. Some patients had not died by the end of study and so these patients
contribute right-censored survival times. At the time of diagnosis, the values of several
covariates were recorded for each patient. The table below describes all variables in
MMA.txt including descriptions along with their codes and values.
Variable
id
time
status
age
gender
Bun
Ca
Hb
Pcells
Protein
Description
Patient identification code
Survival time
Status of last follow-up
Patient’s age at diagnosis
Gender
The levels of blood urea nitrogen
Serum calcium
Haemoglobin
% of plasma cells in the bone
marrow
Indicator of presence of BenceJones protein in the urine
Codes/Values
1–48
In months
0 = censored, 1 = uncensored
In years
1 = male, 2 = female
0 = absent, 1 = present
Use the statistical methods learned in the course to study how these covariates (age,
gender, Bun, Ca, Hb, Pcells, and Protein) affect the survivorship. Your report should
consist of a typed summary of at most 3 pages (letter font size of 12) with an appendix of
at most 3 pages. There should be at least three sections in your report: 1) summary of
your finding, 2) statistical analysis, and 3) conclusion or discussion. In the section of
statistical analysis, you must describe how you select your final model, assess the
adequacy of the model, write and interpret the fitted final model.
Grading policy: 50% for presentation; 50% for statistical analysis