In a previous post, I used statistical data analysis to estimate the probability that my grocery bill is a whole-dollar amount such as $86.00 or $103.00. I used three weeks' grocery receipts to show that the last two digits of prices on items that I buy are not uniformly distributed.
I am just now returning to the office, having spent 3 days in Austin, Texas, attending the South Central SAS Users Group (SCSUG) Educational Forum. The conference was a big success, and I could literally feel the energy in the air. Thanks to the dedication of the executive committee, conference
In a previous post, I discussed computing regression coefficients in different polynomial bases and showed how the coefficients change when you change the basis functions. In particular, I showed how to convert the coefficients computed in one basis to coefficients computed with respect to a different basis. It turns out
Are you afraid of big commitments? Do you like to shop around thoroughly before making a purchase decision? I can't help you with most of Life's Big Choices, but I can help you in one way: I can show you how to learn more about your data set before you
Some of you will remember that in the very early versions of SAS Enterprise Guide, we introduced a unique approach to helping you to learn SAS: an animated "agent" who could suggest your next steps within your project. We furloughed the agent (who appeared usually as a wizard, genie, or
I am pleased to announce that the fine folks at SAS Press have made Chapter 2 of my book, Statistical Programming with SAS/IML Software available as a free PDF document. The chapter is titled "Getting Started with the SAS/IML Matrix Programming Language," and it features More than 60 fully functional
The other day I was at the grocery store buying a week's worth of groceries. When the cashier, Kurt (not his real name), totaled my bill, he announced, "That'll be ninety-six dollars, even." "Even?" I asked incredulously. "You mean no cents?" "Yup," he replied. "It happens." "Wow," I said, with
Chris started a tradition for SAS Press authors to post a photo of themselves with their new book. Thanks to everyone who helped with the production of Statistical Programming with SAS/IML Software.
Dear Readers, You might visit this blog for many reasons, chief among them to learn useful information about SAS. You know that I often post tips about SAS Enterprise Guide, and sometimes people go so far as to call this a "SAS Enterprise Guide" blog*. But for all of the
Suppose that you compute the coefficients of a polynomial regression by using a certain set of polynomial effects and that I compute coefficients for a different set of polynomial effects. Can I use my coefficients to find your coefficients? The answer is yes, and this article explains how. Standard Polynomial
You don't have to wait for Black Friday to save this season...SAS Global Forum Registration opens today! I would definitely recommend checking out the Early Bird Registration Rates.
Let's face it: ever since cats learned how to access the Internet, they've managed to besmirch their prestigious status as the "smarter-if-a-bit-aloof" pet. They've starred in many demeaning YouTube videos, bringing shame to their species for the sake of some cheap laughs. But I'm here to tell you: there are
I just got back from a great conference in San Diego at the 2010 meeting of the Western Users of SAS Software (WUSS) where I gave several presentations on PROC IML and SAS/IML Studio. If you didn't make it to San Diego, you can still read my 2010 paper on
Sampling with replacement is a useful technique for simulations and for resampling from data. Over at the SAS/IML Discussion Forum, there was a recent question about how to use SAS/IML software to sample with replacement from a set of events. I have previously blogged about efficient sampling, but this topic
I recently returned from the 117th Annual Conference of the International Association of Chiefs of Police (IACP) held in Orlando, Florida. It was a tad surreal to be back with the association members and colleagues with whom I worked so closely for almost eight years when I called IACP my
Before the two most recent SAS Global Forums, I wrote posts introducing you to SAS presenters and SAS user presenters. In 2009 (my first SAS Global Forum), I wrote the SAS Presenters Series and introduced SAS professionals including I-Kong Fu, Chris Hemedinger and Daniel Jahn. In 2010, the introductions included
This post is about an estimate, but not the statistical kind. It also provides yet another example in which the arithmetic mean is not the appropriate measure for a computation. First, some background. Last week I read a blog post by Peter Flom that reminded me that it is wrong
Let's pretend for a moment that you don't have SAS installed on all of your office computers. But you've got some great content locked away inside SAS data sets. Is there a way to get to the content of that data, without having to push the data through a SAS
Increase the odds of winning for you and your company in 2011 by attending SAS Global Forum at Caesar’s Palace, April 4-7, in Las Vegas. For the past 36 years, this conference has attracted over 3,000 SAS users and over 400 SAS professionals from across the globe. It’s a sure
Today I'm in San Diego at the 2010 meeting of the Western Users of SAS Software (WUSS). I am giving several presentations on SAS/IML and SAS/IML Studio: A tutorial workshop on SAS/IML Studio for the SAS/STAT User. The material in this tutorial is a small sampling of Chapters 4–11 of
In this blog and in the book Statistical Programming with SAS/IML Software, I present tips and techniques for writing efficient SAS/IML programs for data analysis, simulation, matrix computations, and other topics of interest to statistical programmers. When I was writing my book, one of the reviewers commented that he wasn’t
Many forecasting software packages support hierarchical forecasting. You define the hierarchical relationship of your products and locations, create forecasts at one or more levels, and then reconcile the forecasts across the full hierarchy. In a top-down approach, you generate forecasts at the highest level and apportion it down to lower
How can you change a programming trick into a programming treat? Try this algorithm: If you develop a clever snippet of code, squirrel it away. This snippet is a "trick." If you use the trick a second time, copy and modify the code. The trick has become a "treat." If
Are you up to date on your hotfixes for SAS Enterprise Guide 4.1? If you're not certain of the answer, you'll find out next week when you might see this message appear: This version of SAS Enterprise Guide will expire on December 1st, 2010. If you've applied any SAS Enterprise
The SAS/IML language provides the QUAD function for evaluating one-dimensional integrals. You can also use the QUAD function to compute a double integral as an iterated integral. A One-Dimensional Integration Suppose you want to evaluate the following integral: To evaluate this integral in the SAS/IML language: Define a function module
~Contributed by Sara Jones~ It’s October and there’s a chill in the air. In North Carolina that means State Fair time. Now, for those who are not from the U.S., or for those who are, but don’t live in “the South” -- you may not know what this means. Think
We've just pushed out the localized versions of the Getting Started with SAS Enterprise Guide 4.3 tutorial. This is the tutorial that you'll see when you select Help->Getting Started Tutorial from within SAS Enterprise Guide. Here is a list of the supported languages, and links to the tutorial content: English
I was recently asked how to create a tridiagonal matrix in SAS/IML software. For example, how can you easily specify the following symmetric tridiagonal matrix without typing all of the zeros? proc iml; m = {1 6 0 0 0, 6 2 7 0 0, 0 7 3 8 0,
The question came up on the SAS Enterprise Guide discussion forum: which do you prefer, List Report Wizard (PROC REPORT) or Summary Tables (PROC TABULATE)? And as with most SAS-related questions, the proper response is: "it depends." If you put these two PROCs in the ring with a Google Fight,
Facebook now uses technology to help detect instances of cyberbullying before it gets out of hand. I heard this report on CNN last week, and the Facebook spokesman described their detection techniques as "background technology that I can't really talk about." We don't know for certain what techniques Facebook employs
