HOW TO DISPLAY A LINE PLOT WITH COUNT INFORMATION? In a previously-mentioned paper Sharad and your DSN editor are writing up, there is the above line plot with points. The area of each point shows the count of observations. It’s done in R with ggplot2 (hooray for Hadley). We ... [Read more...]

SOME EMPIRICAL BASES FOR CHOOSING CERTAIN RISK REPRESENTATIONS OVER OTHERS This week DSN posts some thoughts (largely inspired by the work of former colleagues Stephanie Kurzenhäuser, Ralph Hertwig, Ulrich Hoffrage, and Gerd Gigerenzer) about communicating risks to the general public, providing references and delicious downloads where possible. Representations to ... [Read more...]

HOMOPHILY + MAPS WITHOUT MAPPING SOFTWARE In the past, Decision Science News has posted about homophily (“birds of a feather shop together“) and cool, lightweight visualizations (“maps without map packages in R“). Today, both topics come together in Eric Fischer’s fascinating set of images on Flickr called “Race and Ethnicity”(*).  ... [Read more...]

PREDICTING CONSUMER BEHAVIOR FROM SOCIAL NETWORKS This week, Decision Science News is doing a special cross-posting with Messy Matters. The post below is by Sharad Goel and describes work that he and your Decision Science News editor Dan Goldstein are jointly undertaking at Yahoo! Do you know what the #$*! your ... [Read more...]

CHART CRITICS, GRAPHICS CURMUDGEONS, COME ONE COME ALL Once upon a time there was this graph (graph 1). Andrew Gelman went all graphics curmudgeon on it, calling it an “ugly, sloppy bit of data graphics“, so it became this graph (graph 2). Now the question is, which is better: graph 2 or graph 3? ... [Read more...]

[Read more...]

[Read more...]

LATITUDE + LONGITUDE + OVERPLOTTING FIX = MAPS Decision Science News is always learning stuff from colleague, physicist, mathlete, and all-around computer whiz Jake Hofman. Today, it was a quick and clean way to make nice maps in R without using any map packages: just plot the latitude and longitude of your data ... [Read more...]

PROS ARE NOT GETTING BETTER AT FREE THROWS Rick Larrick recently told Decision Science News that baseball players have been getting better over the years in a couple ways. First, home runs and strikeouts have increased. The careless or clueless reader might note that this is curious, for from the ... [Read more...]

COUNTERINTUITIVE PROBLEM, INTUITIVE REPRESENTATION Blog posts about counterintuitive probability problems generate lots of opinions with a high probability. Andrew Gelman and readers have been having a lot of fun with the following probability problem: I have two children. One is a boy born on a Tuesday. What is the probability ... [Read more...]

In baseball, what are the chances the winner will win again against the same opponent the very next day? [Read more...]

INCREDIBLY SIMPLE CALCULATIONS MADE SIMPLE Yes, we all know how to calculate 15% or 20% exactly, but it’s fun to use tipping heuristics and even more fun to make crowded graphs of how they compare to each other. (Sorry for the junky chart. Open for suggestions, in the words of Tom ... [Read more...]

How many observations should you have before constructing a confidence interval? [Read more...]

INCENTIVES TO STATE PROBABILITIES OF BELIEF TRUTHFULLY We have all been there. You are running an experiment in which you would like participants to tell you what they believe. In particular, you’d like them to tell you what they believe to be the probability that an event will occur. ... [Read more...]

THE VALUE OF NOT FOLLOWING INSTRUCTIONS As Shane Frederick has noted, if you say “A bat and a ball cost $1.10. The bat costs $1 more than the ball. How much is the ball?”, you will notice that the vast majority of your friends will say “10 cents” instead of the correct “5 cents”, ... [Read more...]

ALL ABOUT REVOLUTION COMPUTING’S R DISTRIBUTION Decision Science News was intrigued by a company called REvolution Computing that got some attention of late for spinning their own mix of the R language for statistical computing and giving it away for free. So DSN asked to interview them to see ... [Read more...]

NEW YORK TIMES STORY ON THE APPEAL OF R (click to view movie) It is no secret that Decision Science News is crazy about the R language for statistical computing. Find out why R is so great in this New York Times article. Then start to teach yourself R with ... [Read more...]

useR! CONFERENCE, AUGUST 12-14 2008, DORTMUND GERMANY Impressive 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 ... [Read more...]

SIMPLE WAYS TO DETECT AND COMMUNICATE STATISTICAL EFFECTS Decision 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 ... [Read more...]

READ TEXT FILES, RUN MODELS The Decision Science News R video tutorials continue with number 2. (If you missed that last one, you will want to watch R Video Tutorial Number 1 first.) The Goldstein pedometer dataset can be downloaded from http://www.dangoldstein.com/flash/Rtutorial2/pedometer.csv Topics covered this ... [Read more...]