Optional Homework Exercises, Set #5, for IRT Thetahat class #2:

1. Prepare documentation for the IRT08ss class public variables and functions.
(See the NEWMAT10 documentation, or various of the C++ books in 358 or
elsewhere, for examples of what such documentation might look like.)

2. (Very challenging) Add a third option to IRTScore, to read item response data
from a file on the disk, compute one or more of the IRT scale scores for each
person (line) in that data file, and write the results back out to another
disk file.