Posts Tagged ‘ statistics ’

Forecasting Presidential Elections

January 7, 2009
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Forecasting Presidential Elections

Because of Andrew Gelman’s strong, repeated recommendations, I’ve been reading “Forecasting Presidential Elections” by Steven J. Rosenstone for the last two days. It’s quite a remarkable book and complex enough that I’m sure I’ll return t...

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The most popular programming languages in 2008

October 26, 2008
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TIOBE has released the newest ranking for the most popular programming language here. Java remains the top popular programming language. C and C++ follow with Java. I dont' see R in this ranking. Maybe it doesn't belong to this group! Maybe I should ...

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Group-level variances and correlations

September 23, 2008
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This is just a sum-up of what we should do when we try to estimate the group-level variances and correlations but the software failed to do so. As a R and lmer() user, I found this happens often.If this is the case, there are three potential problems...

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Design Flaws in R #2 — Dropped Dimensions

August 19, 2008
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Design Flaws in R #2 — Dropped Dimensions

In a comment on my first post on design flaws in the R language, Longhai remarked that he has encountered problems as a result of R’s default behaviour of dropping a dimension of a matrix when you select only one row/column from that dimension. This was indeed the design flaw that I was going to

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Design Flaws in R #1 — Reversing Sequences

August 6, 2008
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Design Flaws in R #1 — Reversing Sequences

The R language for statistical computing has become the standard for academic statistical research, for the very good reason that it’s better than the alternatives. It’s far from perfect however. I could come up with a long “wish list” of desired features it lacks, but that’s not what I’ll do in this series of posts.

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How to Recover the Missing X(1) for the USL Scalability Model

July 29, 2008
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How to Recover the Missing X(1) for the USL Scalability Model

When it comes to assessing application scalability, controlled measurements of the type that can be obtained with tools like Grinder or LoadRunner, are very useful because they provide a direct measurement of the throughput, X(N), as a function of the...

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Guerrilla Data Analysis Class – Seats Still Available

July 14, 2008
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Guerrilla Data Analysis Class – Seats Still Available

Most operating systems are capable of collecting hundreds of system and performance metrics every second. Even if you only record them once an hour, after a week you will have more than 50,000 samples; after a month you will be staring at almost a quar...

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Get your R on

July 14, 2008
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Get your R on

useR! CONFERENCE, AUGUST 12-14 2008, DORTMUND GERMANYImpressive statistical computing types like Andrew Gelman, Gary King, and others will be presenting at this year’s useR! conference. Decision Science News might just have to hop over and check it out. The program looks great. Those interested in learning R might be interested in our Decision Science News

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An R Wiki

April 21, 2008
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An R Wiki

It’s been ages since I visited the R website, so I don’t know how long they’ve had a wiki. It’s built using DokuWiki, one of my personal favourites. This is a great leap forward for R documentation, which is somewhat notorious for being (a) difficult to find and (b) difficult to understand when you find

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Heuristics for statistics

January 28, 2008
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Heuristics for statistics

SIMPLE WAYS TO DETECT AND COMMUNICATE STATISTICAL EFFECTSDecision Science News is fond of heuristics and the Simonian view that for many problems organisms face, optimization is a fiction and satisficing makes us smart. Statistics is an area in which it is easy to see precision that isn’t there and find “optima” in problems that

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