Programming Tips
17
How to compute Mahalanobis distance in SAS

I recently blogged about Mahalanobis distance and what it means geometrically. I also previously showed how Mahalanobis distance can be used to compute outliers in multivariate data. But how do you compute Mahalanobis distance in SAS? Computing Mahalanobis distance with built-in SAS procedures and functions There are several ways to

85
What is Mahalanobis distance?

I previously described how to use Mahalanobis distance to find outliers in multivariate data. This article takes a closer look at Mahalanobis distance. A subsequent article will describe how you can compute Mahalanobis distance. Distance in standard units In statistics, we sometimes measure "nearness" or "farness" in terms of the

Programming Tips
12
Rounding up, rounding down

SAS has several ways to round a number to an integer. You can round a number up, round it down, or round it to the nearest integer. If your data contain both positive and negative values, you can also round numbers toward zero, or away from zero. The functions that

Programming Tips
95
Loops in SAS

Looping is essential to statistical programming. Whether you need to iterate over parameters in an algorithm or indices in an array, a loop is often one of the first programming constructs that a beginning programmer learns. Today is the first anniversary of this blog, which is named The DO Loop,