Author

Distinguished Researcher in Computational Statistics

Rick Wicklin, PhD, is a distinguished researcher in computational statistics at SAS and is a principal developer of PROC IML and SAS/IML Studio. His areas of expertise include computational statistics, simulation, statistical graphics, and modern methods in statistical data analysis. Rick is author of the books Statistical Programming with SAS/IML Software and Simulating Data with SAS.

5
Shorthand notation for row and column operations

The SAS/IML language enables you to perform matrix-vector computations. However, it also provides a convenient "shorthand notation" that enables you to perform elementwise operation on rows or columns in a natural way. You might know that the SAS/IML language supports subscript reduction operators to compute basic rowwise or columnwise quantities.

6
How to interpret SAS/IML error messages

Errors. We all make them. After all, “to err is human.” Or, as programmers often say, “To err is human, but to really foul things up requires a computer” (Farmer’s Almanac, 1978). This post describes how to interpret error messages from PROC IML that appear in the SAS log. The

3
Launching SAS/IML Studio

I give many presentations and workshops on how to use SAS/IML Studio, and more than once I have been asked about how to launch the program. Sometimes the inquiry hints at mild frustration, such as last week's "How do I RUN the \$%#@# THING!!!!" The email I got this week

2
Resampling and simulating my grocery bills

In a previous post, I used statistical data analysis to estimate the probability that my grocery bill is a whole-dollar amount such as \$86.00 or \$103.00. I used three weeks' grocery receipts to show that the last two digits of prices on items that I buy are not uniformly distributed.

0
Regression coefficients for orthogonal polynomials

In a previous post, I discussed computing regression coefficients in different polynomial bases and showed how the coefficients change when you change the basis functions. In particular, I showed how to convert the coefficients computed in one basis to coefficients computed with respect to a different basis. It turns out