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SSPA Blog: Back to school on CDISC topics!!!

By Michael Carniello posted 08-19-2013
I'm excited to share the details about two great CDISC-related webinars our section is sponsoring in September! Helping Data Work Together: Harmonizing CRF Design with CDISC SDTM Standards • Tuesday, September 10, 2013, 12:00 p.m. - 1:30 p.m. (Eastern) • Presented by industry experts Steve Kirby, Erica Greer, and Mario Widel. • Focuses on strategies to build a clear path from clinical data collection to SDTM data submission. Preparing to Share CDISC SDTM Data: A Practical Look at How to Conduct and Document Review of SDTM Data and Documentation • Tuesday, September 24, 2013, 12:00 p.m. - 1:30 p.m. (Eastern) • Presented by Steve Kirby, Mario ...

Error in glmnet

By Guy-vanie Miakonkana posted 06-23-2013
Greetings! I am trying to run the "cv.glmnet "function in R. It runs successfully when alpha=0.5 or 0. See below cv.glmnet(x=x,y=f,family="poisson", alpha=0.5 , offset=rep(log(poffset), length(f))) cv.glmnet(x=x,y=f,family="poisson", alpha=0 , offset=rep(log(poffset), length(f))) However when I specify alpha =1 cv.glmnet(x=x,y=f,family="poisson", alpha=1 , offset=rep(log(poffset), length(f))) I get the following error message: Error: Matrices must have same number of columns in .local(x, y, ...) Any help on this ? Thanks!

Adative elastic net in R

By Guy-vanie Miakonkana posted 06-08-2013
Greetings! I know that the package "glmnet" performs elastic net for Poisson, Logistic and multinomial regressions. Does any one know a package or a way to fit adaptive elastic net in R ? Thanks!

SSPA Blog: Mixing Statistical Models without Expensive Kitchen-Aid Tools

By Michael Carniello posted 04-10-2013
Please forgive the silly subject line above; I was trying to draw you into this post, which highlights an upcoming webinar sponsored by the Section for Statistical Programmers and Analysts. Donald Hedeker, at the University of Illinois at Chicago, will be presenting a short workshop on "Mixed Models for Longitudinal Categorical Outcomes." The webinar will be held Tuesday, April 30, 2013, from 12:00 p.m. - 1:30 p.m. Eastern Time. This workshop will focus on analysis of longitudinal data using mixed models, specifically with a non-continuous outcome.　 When responses are repeatedly measured on the same individual or clustered within a group of similar individuals ...

SSPA Blog: Upcoming Webinar on Missing Value Imputation

By Rick Wicklin posted 03-27-2013
The ASA Section for Statistical Programmers and Analysts (SSPA) is proud to present the next topic in its webinar training series: Title: Issues and Guidelines of Multiple Imputation in Practice Presenter: Aya Mitani, MPH, Stanford University Department of Medicine Date and Time: Wednesday, April 17, 2013, 12:00 p.m. - 1:30 p.m. Eastern time Registration Deadline: Monday, April 15, at 12:00 p.m. Eastern time Multiple imputation (MI) is a simulation-based method for handling missing data. While in theory MI yields valid results when data are missing at random (MAR), in practice the story is more nuanced. This webinar will discuss common issues ...

SSPA Blog: Upcoming Webinar on SAS Statistical Graphics

By Rick Wicklin posted 03-20-2013
The ASA Section for Statistical Programmers and Analysts (SSPA) is proud to present the next topic in its webinar training series: Creating Statistical Graphics in SAS Warren F. Kuhfeld, PhD (SAS Institute) Tuesday, March 26, 2013, 12:00 p.m. - 1:30 p.m. Eastern time Registration Deadline: Friday, March 22, at 12:00 p.m. Eastern time Effective graphics are indispensable in modern statistical analysis. SAS provides statistical graphics through ODS Graphics. This tutorial is intended for statistical users and covers the use of ODS Graphics from start to finish in statistical analysis. If you haven't seen SAS graphs lately, then you haven't seen ...

Slice, Dice, and TABULATE: A Webinar for Statistical Programmers

By Rick Wicklin posted 01-22-2013
The ASA Section for Statistical Programmers and Analysts (SSPA) is proud to present the next topic in its webinar training series : Maximizing the Use of SAS PROC TABULATE Sunil Gupta (Gupta Programming) Wednesday, February 27, 12:00 p.m. - 1:30 p.m. Eastern time Registration Deadline: Monday, February 25, at noon Eastern time The TABULATE procedure enables you to slice and dice your data, and present summary statistics in a single compact table. The TABULATE procedure is most powerful when you have multiple classification variables, possibly nested within each other. If you have been using PROC MEANS and SUMMARY to compute ...

Using R Effectively to Conduct Linear Regression Analyses

By Michael Carniello posted 01-02-2013
I'm posting this note in the ASA's Blog Space to share beyond our Section for Statistical Programmers and Analysts (SSPA) ... there's an exciting webinar on R set for next week: Using R Effectively to Conduct Linear Regression Analyses Isabella R. Ghement, Ph.D. (Ghement Statistical Consulting Co.) Wednesday, January 9, 12:00 p.m. - 1:30 p.m. Eastern time Registration Deadline: Monday, January 7, at noon Eastern time http://www.amstat.org/sections/sspa/webinarseries.cfm This webinar demonstrates the effective use of R for performing linear regression analyses, while also emphasizing good practices to be followed when implementing ...

SSPA Blog: We're Sexy and We Know It

By Michael Carniello posted 09-20-2012
The work we do as programmers and analysts has just been described as the "sexiest job" going, according the Harvard Business Review (HBR)! Check out the article here (by Thomas Davenport and D.J. Patil). This concept is not new; in 2009, Hal Varian, the chief economist at Google was quoted in the McKinsey Quarterly as saying "I keep saying the sexy job in the next ten years will be statisticians." The focus of the HBR story is on "big data," but it's relevant to all of us, no matter if we work in industry, academia or government. I definitely think this article is worth your time to read. Deep in the story, the author claims: "Start with ...

SSPA Blog: Support for Students and Recent Graduates to Attend Conferences

By Rick Wicklin posted 09-12-2012
The American Statistical Association (ASA) has made it a priority to attract and retain statistical practitioners in a wide variety of fields. As Bob Rodriguez said in his Presidential address, the ASA needs to be the “Big Tent” for all statisticians . One area that the ASA has been working on is providing reasons for statistical programmers to become part of the ASA. The Section for Statistical Programmers and Analysts (SSPA) was founded in 2009 to support programmers. The section has worked hard to provide webinars on topics such as CDISC standards and job interview skills , which appeal to those of us “down in the trenches.” Another ...

SSPA Blog: A webinar on The Job Interview!

By Michael Carniello posted 06-19-2012
This blog post is about an exciting webinar being offered by our section: "Critical Interview Strategies and Skills" (Noon to 1:30 Eastern, July 10 2012). I wish I had taken this webinar earlier in my career! My initial set of job interviews resulted in no job offers; it took me too long to understand that it was me - not them! This is a great opportunity for ASA members to learn: * How to manage the stages of an interview * Critical strategies to engage the interviewer * How to distinguish yourself from other candidates * The key to an influential conversation that positions you for the hire * What you MUST do at the end of every ...

SSPA Blog: Insight into the Graph Building Process

By Michael Carniello posted 05-15-2012
As statistical programmers, we're frequently asked to create graphs depicting some sort of statistical summary of data. Sometimes we have few options - the instructions imposed upon us are quite clear and unambiguous. Other times, though, we have some freedom to decide how to best present the information. Insight into what the New York Times does is archived on this site: http://chartsnthings.tumblr.com/ which is managed by the NYT graphics staff (although it's a tumblr site, not on nytimes.com). I don’t necessarily agree with all of their choices. However, it's fascinating to watch a graph evolve from some initial sketches on paper ...

SSPA Blog: The Learning Never Stops

By Michael Carniello posted 04-09-2012
The other day at work, a statistical topic came up in a discussion (as happens frequently when one is a statistical analyst). I was not that well-versed in the subject area, so looked around the internet for some knowledge help. One link led to another, and soon I was rifling through a variety of sites associated with college courses in statistics and programming. I think spending some time on these sites is a great way to to learn something new - there are typically lecture notes, book references, homework problems and homework solutions. This reminds of auditing a class in college in the old days; you could sit in on the lectures, do the readings and ...

SSPA Conference Grant Program for Students and Recent Graduates

By Rick Wicklin posted 03-22-2012
The ASA Section for Statistical Programmers and Analysts (SSPA) has a small grant program to pay the primary registration fees for section members who have recently graduated and who want to attend an ASA conference. Eligibility • The applicant is a current student or has graduated from a college or university within the previous three years with a degree in statistics, biostatistics, applied mathematics, or a related field. • The applicant must be a member of the SSPA in the year for which funds are requested. • The conference must be an ASA-sponsored conference such as the Joint Statistical Meetings (JSM) or the ASA Conference on Statistical Practice. ...

SSPA Blog: New programming languages and new statistical techniques: Irrelevant or necessary?

By Rick Wicklin posted 03-08-2012
I like to think of myself as "current" regarding statistical programming, but when I read blogs and attend talks by younger researchers, I am amazed by the number of newer computer languages that are in vogue. Of course, "newer" depends on how old you are! For many programmers, "newer" means either "since I left school" or "since I arrived at my current job." For me, newer languages include Groovy, Haskell, Julia, and Lua, just to name a few. Crista Videira Lopes, an academic researcher in programming languages, recently wrote a long but interesting essay on recent programming languages . She makes several interesting claims: Lopes claims that ...

SSPA Blog: Conferences and workshops: Too hot, too cold, or just right?

By Rick Wicklin posted 01-11-2012
I almost didn’t see it. On the library bookshelf, wedged between heftier hardback tomes, was a little paperback booklet titled How to Test Normality and Other Distributional Assumptions , by Samuel S. Shapiro. It was so thin that the title didn’t fit on the book’s spine. Nevertheless, I picked it up, thumbed through it, and immediately wished I had found this book ten years ago. Although written in 1980 and therefore somewhat outdated, this booklet neatly summarizes a wealth of facts, examples, and references that I have seen over the years into a concise desk reference. It is clearly meant for practitioners such as an engineer on the floor of a manufacturing ...

SSPA Blog: Analyzing the analyst

By Michael Carniello posted 12-12-2011
I’ve recently been using statistical programming recently to analyze … statistical programming! I thought I’d share a couple of thoughts on this topic. The Unix server which handles statistical programming where I work is used by dozens of programmers, analysts and statisticians. Throughout the course of a normal day, there are occasions of slow processing times. At least, that’s the perception I have. I was wondering why this might be – I suspected either an increase in programming jobs, or an increase in the “depth” of particular programming jobs (eg, complex statistical models perhaps, or large simulations). To analyze what was going on, I needed ...

SSPA Blog: Testing statistical software: Ways to minimize the pain

By Rick Wicklin posted 11-28-2011
I love to write programs. Statistical programming is my job, but for my blog I write programs for fun. Testing? Not so much fun, but a necessary part of my job. To me, programming is like eating candy or a mouth-watering dessert. Testing is like brushing my teeth afterwards. If I eat sweets and don’t brush, my teeth will decay and fall out of my mouth. My teeth will yellow and my breath will stink. If I try to chew something, a tooth might actually break and need expensive repairs. In the same way, testing enables me to take preventive steps to ensure that my programs don’t fall apart. I can make sure that ...

SSPA Blog: Le Tour de France - Is it easier now than in the past?

By Patrick Rhodes posted 11-07-2011
The cyclists are staring straight ahead into the abyss - the ’10,000 mile stare’ that arrives at the end of the second week of racing the Tour de France (henceforth noted as TdF). Their legs are wooden from having already pushed the pedals over a quarter of a million rotations. Riders’ hearts are weary, having beat an additional half a million times more than otherwise. Like Roman chariot drivers, team managers flog their racers over radios, pushing them to go on, "Attack! Go to the front! Faster!" Hunched low over the handlebars, sweat cascading down their gaunt faces, their bodies strain under the broiling French summer sun. Several torturous hours go by and ...

SSPA Blog: Bayes Theorem and the News

By Michael Carniello posted 10-19-2011
This post does not deal with the programming aspect of our work, but interesting enough to pass along, I think: Statistical methods are frequently used in a variety of court cases; this story concerns a case in which Bayes' theorem was ruled invalid. According to the article in The Guardian (UK), the judge: decided that Bayes' theorem shouldn't again be used unless the underlying statistics are "firm". The decision could affect drug traces and fibre-matching from clothes, as well as footwear evidence, although not DNA. The article describes a murder case in which the theorem was used to compute the probability that a particular set of shoeprints ...