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.
At a conference last week, a presenter showed SAS statements that compute the logarithm of a probability density function (PDF). The log-PDF is a a common computation because it occurs when maximizing the log-likelihood function. The presenter computed the expression in SAS by using an expression that looked like y
Who was the oldest person elected president of the United States? How about the youngest? Who was the oldest when he left office? Let's look at some data. Wikipedia has a page that presents a table of the presidents of the US by age. It lists the dates for which
If you obtain data from web sites, social media, or other unstandardized data sources, you might not know the form of dates in the data. For example, the US Independence Day might be represented as "04JUL1776", "07/04/1776", "Jul 4, 1776", or "July 4, 1776." Fortunately, the ANYDTDTE informat makes it
