Uncategorized

Rick Wicklin 0
Efficient acceptance-rejection simulation

A few days ago on the SAS/IML Support Community, there was an interesting discussion about how to simulate data from a truncated Poisson distribution. The SAS/IML user wanted to generate values from a Poisson distribution, but discard any zeros that are generated. This kind of simulation is known as an

Learn SAS
Kathy Council 0
More eBooks for everyone

SAS Publishing has been offering eBooks through partners like Amazon, Apple, and Google, for a number of years. Our content is also available through subscription-based companies like Books 24x7, Safari, and EBSCO. We have learned that taking content developed for hardcopy and turning it into an ebook is not a

Rick Wicklin 0
Inverse hyperbolic functions in SAS

I was recently asked, "Does SAS support computing inverse hyperbolic trigonometric functions?" I was pretty sure that I had used the inverse hyperbolic trig functions in SAS, so I was surprised when I read the next sentence: "I ask because I saw a Usage Note that says these functions are

Learn SAS
0
Early praise for PROC DOCUMENT by Example Using SAS

Hot off the press and debuting at NESUG is Michael Tuchman's new book, PROC DOCUMENT by Example Using SAS. Tuchman's book demonstrates the practical uses of the DOCUMENT procedure, a part of the Output Delivery System, in SAS 9.3. The DOCUMENT procedure allows general SAS users to store and manage

Mike Gilliland 0
Simple methods and ensemble forecasting of elections

Two enduring principles of forecasting are that simple methods can work as well as fancy methods, and that combining (averaging)  forecasts, also known as "ensemble forecasting," will usually result in more accurate predictions than the individual methods being averaged. We saw a good demonstration of these principles in Tuesday's election

Learn SAS
Shelly Goodin 0
SAS author's tip: The basics of decision trees

This week's SAS tip is from Barry de Ville and his book Decision Trees for Business Intelligence and Data Mining: Using SAS Enterprise Miner.  Barry is a technical and analytical consultant at SAS. To learn more about Barry and his forthcoming new edition of the book, following this week's excerpt, visit his author

Shelley Sessoms 0
A snapshot of SCSUG 2012

I’ve just returned from my third regional conference this year…SCSUG in Houston. We had great attendance; 207 folks registered for the event! And several of our authors were there: Kirk Lafler, Sanjay Matange and Cynthia Zender. SAS’ very own Paul Kent gave the keynote address on big data and high

Mike Gilliland 0
The predictive power of nonsense

The 2012 US Presidential race comes to a close today (thankfully), and there is no shortage of wacky indicators predicting the winner: Iowa Electronic Markets FiveThirtyEight PollyVote University of Colorado In primitive times a diviner could foretell the future by poisoning a chicken -- whether it lived or died provided

Rick Wicklin 0
Constructing common covariance structures

I recently encountered a SUGI30 paper by Chuck Kincaid entitled "Guidelines for Selecting the Covariance Structure in Mixed Model Analysis." I think Kincaid does a good job of describing some common covariance structures that are used in mixed models. One of the many uses for SAS/IML is as a language

Advanced Analytics
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

0
3 things you should know about The Little SAS Book, Fifth Edition

You’ve known it, you’ve loved it. Your copy’s pages are worn, torn, or coffee-stained, and yet it’s still as beloved as ever. It’s your Little SAS Book. It belongs on every SAS programmer’s bookshelf, and it’s now even better. Susan Slaughter and Lora Delwiche have worked to help you improve

1 224 225 226 227 228 281