Course 613.. Assignments

McGill University, Department of Epidemiology, Biostatistics and Occupational Health

EPIB 613: Introduction to Statistical Software (Fall 2005)

Assignment 5, due November 14

Working in teams of two...


These two files contain PSA values [pre-] and [post-] treatment of prostate cancer *.

(a) Create a 'wide' PSA file of 25 log-base-2 PSA values per man (some will be missing, if PSA not measured 25 times). Print some excerpts.

(b)From the dataset created in (a), create a long file, with just the observations containing the non-missing log-base-2 PSA values [OUTPUT statement in DATA step]. Print and plot some excerpts.

(c) From the dataset created in (b), create a wide file [ RETAIN, first. and last. helpful here; or use PROC TRANSPOSE ]. Print some excerpts.

* The order of the variables is given in this
sas program . Some of the code in the program may also be of help.


Put all of the program steps and output into a single .txt file. JH will use a mono-spaced font such as Courier to view it -- that way the alignment should be ok. Interleave DATA and PROC statements with output and conclusions, and use helpful titles (produced by SAS, but to your specifications) over top of each output. Get SAS to set up the output so that there are no more that 65 horizontal characters per line -- that way, lines won't wrap-around even when the font used to view your file is increased. Show relevant excerpts rather than entire listings of datafiles. Annotate liberally. Submit the text file electronically (i.e., by email) to JH by 9 am on Monday Nov 14.

(updated Nov 8, 2005)