The DO Loop
Statistical programming in SAS with an emphasis on SAS/IML programs![Simulation and sampling in Las Vegas](https://blogs.sas.com/content/iml/files/2011/08/tipsheet.png)
If you haven't signed up for SAS Global Forum 2011 in Las Vegas, you'd better get moving: February 28 is the last day for early registration and the discounted hotel prices. You should also sign up for the pre-conference statistical tutorials, which are filling up fast! I was tempted to
![Bias and covariance explained to an 11-year-old](https://blogs.sas.com/content/iml/files/2011/08/target.png)
I was inspired by Chris Hemedinger's blog posts about his daughter's science fair project. Explaining statistics to a pre-teenager can be a humbling experience. My 11-year-old son likes science. He recently set about trying to measure which of three projectile launchers is the most accurate. I think he wanted to
![SAS/IML operations compared with PROC SQL: Part 1](https://blogs.sas.com/content/iml/files/2011/08/t_sql_mono.png)
I don't know much about the SQL procedure, but I know that it is powerful. According to the SAS documentation for the SQL procedure, "PROC SQL can perform some of the operations that are provided by the DATA step and the PRINT, SORT, and SUMMARY procedures." Recently, a fellow blogger,
![How to build a vector from expressions](https://blogs.sas.com/content/iml/files/2017/01/AdvancedAnalytics-2.png)
If you are a statistical programmer, sooner or later you have to compute a confidence interval. In the SAS/IML language, some beginning programmers struggle with forming a confidence interval. I don't mean that they struggle with the statistics (they know how to compute the relevant quantities), I mean that they
![Comedy vs. Drama: A comparative histogram of TV's top earners](https://blogs.sas.com/content/iml/files/2011/08/actorpay.png)
The Flowing Data blog posted some data about how much TV actors get paid per episode. About a dozen folks have created various visualizations of the data (see the comments in the Flowing Data blog), several of them very glitzy and fancy. One variable in the data is a categorical
![Converting matrix subscripts to indices](https://blogs.sas.com/content/iml/files/2011/08/t_sub2ind.png)
Suppose that you want to create a matrix in SAS/IML software that has a special structure, such as a tridiagonal matrix. How do you do it? Or suppose that you want to find elements of a matrix A such that A[i,j] satisfies a certain condition. How do you get the