Rick Wicklin, PhD, is a distinguished researcher in computational statistics at SAS and is a principal developer of SAS/IML software. 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.
The SAS analytical documentation has a new look. Beginning with the 14.2 release of the SAS analytical products (which shipped with SAS 9.4m4 in November 2016), the HTML version of the online documentation has moved to a new framework called the Help Center. The URL for the online documentation is
This article shows how to solve mixed integer linear programming (MILP) problems in SAS. In a mixed integer problem, some of the variables in the problem are integer-valued whereas others are continuous. The objective function is a linear function of the variables and the variables can be subject to linear
For SAS programmers, the PUT statement in the DATA step and the %PUT macro statement are useful statements that enable you to display the values of variables and macro variables, respectively. By default, the output appears in the SAS log. This article shares a few tips that help you to
Last week I wrote about the 10 most popular articles from The DO Loop in 2016. The popular articles tend to be about elementary topics that appeal to a wide range of SAS programmers. Today I present an "editor's choice" list of technical articles that describe more advanced statistical methods
In the beginning, SAS created procedures and output. The output was formless and void. Then SAS said, "Let there be ODS," and there was ODS. Customers saw that ODS was good, and SAS separated the computation from the display and management of output. The preceding paragraph oversimplifies the SAS Output
“La Quinta” is Spanish for “next to Denny’s.” -- Mitch Hedberg, comedian Mitch Hedberg's joke resonates with travelers who drive on the US interstate system because many highway exits feature both a La Quinta Inn™ and a Denny's® restaurant within a short distance of each other. But does a
I wrote 105 posts for The DO Loop blog in 2016. My most popular articles were about data analysis, SAS programming tips, and elementary statistics. Without further ado, here are the most popular articles from 2016. Data Analysis and Visualization Start with a juicy set of data and an interesting
How can you generate data that contains outliers in a simulation study? The contaminated normal distribution is a simple but useful distribution you can use to simulate outliers. The distribution is easy to explain and understand, and it is also easy to implement in SAS. What is a contaminated normal
In some applications, you need to optimize a linear objective function of many variables, subject to linear constraints. Solving this problem is called linear programming or linear optimization. This article shows two ways to solve linear programming problems in SAS: You can use the OPTMODEL procedure in SAS/OR software or
Out of the bosom of the Air, Out of the cloud-folds of her garments shaken, Over the woodlands brown and bare, Over the harvest-fields forsaken, Silent, and soft, and slow Descends the snow. "Snow-flakes" by Henry Wadsworth Longfellow Happy holidays to all my readers! In my last post I showed
