## VIS 2015 – Wednesday

October 28, 2015
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The second full day of VIS 2015 brought lots of papers on applications and design studies, and also a panel on solved problems in visualization. As on the first day, I have some observations and thoughts. Here are two things I keep noticing and it baffles me that so many people don’t seem to be … Continue reading VIS 2015 – Wednesday

## Discussion of the Theranos Controversy with Elizabeth Matsui

October 28, 2015
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Theranos is a Silicon Valley diagnostic testing company that has been in the news recently. The story of Theranos has fascinated me because I think it represents a perfect collision of the tech startup culture and the health care culture and how combining them together can generate unique problems. I talked with Elizabeth Matsui, a

## Graphical Modeling Mimics Selective Attention: Customer Satisfaction Ratings

October 28, 2015
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As shown by the eye tracking lines and circles, there is more on the above screenshot than we can process simultaneously. Visual perception takes time, and we must track where the eye focuses by recording sequence and duration. The "50% off" ...

## The HAC Emperor has no Clothes

October 28, 2015
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Well, at least in time-series settings. (I'll save cross sections for a later post.)Consider a time-series regression with possibly heteroskedastic and/or autocorrelated disturbances, $$y_t = x_t' \beta + \varepsilon_t$$. A popular ap...

## Fooled by the big bad digital marketing data

October 28, 2015
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My latest piece in HBR (link) deals with the uncomfortable truth that digital marketing is just as wasteful as off-line advertising. This waste is a result of the prevalence of fake data. Because so much money is channeled into digital these days--all the big Web companies are essentially advertising agencies, scammers are everywhere siphoning off the advertisers' dollars. As I demonstrate in the piece, these scammers can make a good…

## Balancing profit and learning in A/B testing

October 28, 2015
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A/B testing, or split testing, is commonly used in web marketing to decide which of two design options performs better. If you have so many visitors to a site that the number of visitors used in a test is negligible, conventional randomization schemes are the way to go. They’re simple and effective. But if you […]

## Hi-tech hoops: Characterizing the spatial structure of defensive skill in professional basketball

October 28, 2015
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Joshua Vogelstein points me to this article by Alexander Franks, Andrew Miller, Luke Bornn, and Kirk Goldsberry and writes: For some reason, I feel like you’d care about this article, and the resulting discussion on your blog would be fun. Hey—label your lines directly! Cool! Ummm . . . no. No. Really, really, really, really […] The post Hi-tech hoops: Characterizing the spatial structure of defensive skill in professional basketball…

## Monte Carlo simulation for contingency tables in SAS

October 28, 2015
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The FREQ procedure in SAS supports computing exact p-values for many statistical tests. For small and mid-sized problems, the procedure runs very quickly. However, even though PROC FREQ uses efficient methods to avoid unnecessary computations, the computational time required by exact tests might be prohibitively expensive for certain tables. If […] The post Monte Carlo simulation for contingency tables in SAS appeared first on The DO Loop.

## VIS 2015 – Tuesday

October 28, 2015
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IEEE VIS 2015 started today. The first sessions included network visualization and projections, as well as a panel on the use of color in visualization. As usual, this is very selective: only the things I happened to see, and of those only the ones I felt strongly enough to mention here. You can follow the conference … Continue reading VIS 2015 – Tuesday

## Piecewise linear trends

October 28, 2015
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I prepared the following notes for a consulting client, and I thought they might be of interest to some other people too. Let denote the value of the time series at time , and suppose we wish to fit a trend with correlated errors of the form     where represents the possibly nonlinear trend […]

## Super-topical NBA post!!!

October 27, 2015
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Paul Alper writes: Now that his team has won the NBA Championship, I am surprised that you have not commented on Curry and his mouthguard. The link is from May 8, 2015. Notice that mouthguard out is mouthguard chewed! From the article: Curry says his mouthguard routines are completely random, but apparently he’s now well […] The post Super-topical NBA post!!! appeared first on Statistical Modeling, Causal Inference, and Social…

## Non-linear growth curves with Stan

October 27, 2015
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I suppose the go to tool for fitting non-linear models in R is nls of the stats package. In this post I will show an alternative approach with Stan/RStan, as illustrated in the example, Dugongs: "nonlinear growth curve", that is part of Stan's document...

## Workshop on replication in economics

October 26, 2015
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Jan Hoffler sends along this information: YSI workshop with Richard Ball, Johannes Pfeifer, Edward Miguel, Jan H. Höffler, and Thomas Herndon January 6 – 7, San Francisco, Mozilla Science Lab The workshop will take place right after the Annual Meeting of the American Social Sciences Associations, which includes the Annual Meeting of the American Economic […] The post Workshop on replication in economics appeared first on Statistical Modeling, Causal Inference,…

## Think Bayes: Bayesian Statistics Made Simple

October 26, 2015
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By some piece of luck, I came upon the book Think Bayes: Bayesian Statistics Made Simple, written by Allen B. Downey and published by Green Tea Press [which I could relate to No Starch Press, focussing on coffee!, which published Statistics Done Wrong that I reviewed a while ago] which usually publishes programming books with […]

## Think Bayes: Bayesian Statistics Made Simple

October 26, 2015
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By some piece of luck, I came upon the book Think Bayes: Bayesian Statistics Made Simple, written by Allen B. Downey and published by Green Tea Press [which I could relate to No Starch Press, focussing on coffee!, which published Statistics Done Wrong that I reviewed a while ago] which usually publishes programming books with […]

## Think Bayes: Bayesian Statistics Made Simple

October 26, 2015
By

By some piece of luck, I came upon the book Think Bayes: Bayesian Statistics Made Simple, written by Allen B. Downey and published by Green Tea Press [which I could relate to No Starch Press, focussing on coffee!, which published Statistics Done Wrong that I reviewed a while ago] which usually publishes programming books with […]

## More chart drama, and data aggregation

October 26, 2015
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Robert Kosara posted a response to my previous post. He raises an important issue in data visualization - the need to aggregate data, and not plot raw data. I have no objection to that point. What was shown in my...

## Don’t miss this one: “Modern Physics from an Elementary Point of View”

October 26, 2015
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I was googling *back of the envelope* for a recent post and I came across these lecture notes by Victor Weisskopf from 1969. I can no longer really follow this sort of thing—I really really wish this had been my textbook back when I was studying physics. If they’d taught us this stuff, I might’ve […] The post Don’t miss this one: “Modern Physics from an Elementary Point of View”…

## Theranos and ethics

October 26, 2015
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I have to admit I missed the hype about Elizabeth Holmes, and only learned about her from the Wall Street Journal hit job that came out last week (link). It feels like I arrived to the party after the police has shut the fun down! Holmes had been profiled in all the important places--no doubt many of her interviewers are feeling a bit red-faced. She dropped out of Stanford to…

## On deck this week

October 26, 2015
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Lotsa hoops this week: Mon: Don’t miss this one: “Modern Physics from an Elementary Point of View” Tues: Super-topical NBA post!!! Wed: Hi-tech hoops: Characterizing the spatial structure of defensive skill in professional basketball Thurs: You won’t be able to stop staring at this original Hot Hand preprint Fri: Stop screaming already: Exaggeration of effects […] The post On deck this week appeared first on Statistical Modeling, Causal Inference, and…

## On deck this week

October 26, 2015
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Lotsa hoops this week: Mon: Don’t miss this one: “Modern Physics from an Elementary Point of View” Tues: Super-topical NBA post!!! Wed: Hi-tech hoops: Characterizing the spatial structure of defensive skill in professional basketball Thurs: You won’t be able to stop staring at this original Hot Hand preprint Fri: Stop screaming already: Exaggeration of effects […] The post On deck this week appeared first on Statistical Modeling, Causal Inference, and…

## Exact tests in PROC FREQ: What, when, and how

October 26, 2015
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Did you know that the FREQ procedure in SAS can compute exact p-values for more than 20 statistical tests and statistics that are associated with contingency table? Mamma mia! That's a veritable smorgasbord of options! Some of the tests are specifically for one-way tables or 2 x 2 tables, but many apply […] The post Exact tests in PROC FREQ: What, when, and how appeared first on The DO Loop.

## When Details Hide the Story

October 26, 2015
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Kaiser Fung doesn’t like this graphic that accompanied a recent story about the bird flu in the Wall Street Journal. His redesign shows a lot less overlap and a lot more detail; so much, in fact, that it obscures the point of the chart. Here is the offending graphic. The overlapping circles are hard to read with … Continue reading When Details Hide the Story