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Rick Wicklin 0
Compute the log-determinant of a matrix

The determinant of a matrix arises in many statistical computations, such as in estimating parameters that fit a distribution to multivariate data. For example, if you are using a log-likelihood function to fit a multivariate normal distribution, the formula for the log-likelihood involves the expression log(det(Σ)), where Σ is the

Data Visualization
Sanjay Matange 0
Violin Plots

Over the past month or more, I have been in a conversation with SAS user James Marcus, on creation of some new displays for visual communication of uncertainty.  These include display of densities using a "Violin" plot, "Density Strips" and more.   With his permission, I can share some of the

Learn SAS
Shelly Goodin 0
SAS author's tip: The concept of a sampling distribution

This week's tip is from Professor Willbann D. Terpening and his book Statistical Analysis for Business Using JMP. If you're intrigued by the following excerpt, visit Terpening's author page for additional bonus book content. And take a look at his previously featured tip The Student t-distribution, on this blog: The following excerpt is from

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