## Open-source tools for running online field experiments

July 10, 2014
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Dean Eckles points me to this cool new tool for experimentation: I [Eckles] just wanted to share that in a collaboration between Facebook and Stanford, we have a new paper out about running online field experiments. One thing this paper does is describe some of the tools we use to design, deploy, and analyze experiments, […] The post Open-source tools for running online field experiments appeared first on Statistical Modeling,…

## Around the blogosphere

July 10, 2014
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A number of folks have reacted to various blogs and talks I have recently given. I'm glad that my writing has inspired others, and I recommend reading these wonderful responses. *** Diane Ravitch, the eminent scholar of New York education and author of several great books, found my 2011 post about Bill Gates's view of education. Here is her reaction: How refreshing to know that statisticians like Kaiser Fung are…

## Return of the barrel

July 10, 2014
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Back in 2008, I wrote about this unfortunate chart by the Guardian (link): The barrel imagery interferes with communicating the data. The green portion looks about the same size as the red portion when the number is four times smaller....

## “P.S. Is anyone working on hierarchical survival models?”

July 9, 2014
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Someone who wishes to remain anonymous writes: I’m working on building a predictive model (not causal) of the onset of diabetes mellitus using electronic medical records from a semi-panel of HMO patients. The dependent variable is blood glucose level. The unit of analysis is the patient visit to a network doctor or hospitalization in a […] The post “P.S. Is anyone working on hierarchical survival models?” appeared first on Statistical…

## Two unsolved problems of Big Data studies: confirmation and controls

July 9, 2014
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A postscript on the post about ProPublica's display of ambulance spending data on Junk Charts. This chart (of which I excerpted the top) is used in support of an article exposing potential fraud by ambulance operators in New Jersey. But the chart by itself is not convincing evidence of fraud. It presents a symptom, and that's really all exploratory analysis of observational data can realistically achieve. The ProPublica investigation is…

## A small step for interactivity

July 9, 2014
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Alberto links to a nice Propublica chart on average annual spend per dialysis patient on ambulances by state. (link to chart and article) It's a nice small-multiples setup with two tabs, one showing the states in order of descending spend...

## Scatter plots with logarithmic axes…and how to handle zeros in the data

July 9, 2014
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If you are trying to visualize numerical data that range over several magnitudes, conventional wisdom says that a log transformation of the data can often result in a better visualization. This article shows several ways to create a scatter plot with logarithmic axes in SAS and discusses some of the […]

## Are Consumer Preferences Deep or Shallow?

July 8, 2014
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John Hauser, because no one questions his expertise, is an excellent spokesperson for the viewpoint that consumer preferences are real, as presented in his article "Self-Reflection and Articulated Consumer Preferences." Simply stated, preferences are e...

## Automatic bias correction doesn’t fix omitted variable bias

July 8, 2014
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Page 94 of Gelman, Carlin, Stern, Dunson, Vehtari, Rubin “Bayesian Data Analysis” 3rd Edition (which we will call BDA3) provides a great example of what happens when common broad frequentist bias criticisms are over-applied to predictions from ordinary linear regression: the predictions appear to fall apart. BDA3 goes on to exhibit what might be considered … Continue reading Automatic bias correction doesn’t fix omitted variable bias → Related posts: Frequentist…

## Higgs Discovery two years on (1: “Is particle physics bad science?”)

July 8, 2014
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July 4, 2014 was the two year anniversary of the Higgs boson discovery. As the world was celebrating the “5 sigma!” announcement, and we were reading about the statistical aspects of this major accomplishment, I was aghast to be emailed a letter, purportedly instigated by Bayesian Dennis Lindley, through Tony O’Hagan (to the ISBA). Lindley, according […]

## Just wondering

July 8, 2014
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It would be bad news if a student in the class of Laurence Tribe or Alan Dershowitz or Ian Ayres or Edward Wegman or Matthew Whitaker or Karl Weick or Frank Fischer were to hand in an assignment that is obviously plagiarized copied from another source without attribution. Would the prof have the chutzpah to […] The post Just wondering appeared first on Statistical Modeling, Causal Inference, and Social Science.

July 8, 2014
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Recently we released googleVis 0.5.3 on CRAN. The package provides an interface between R and Google Charts, allowing you to create interactive web charts from R.Screen shot of some of the Google ChartsAlthough this is mainly a maintenance release, I'd...

## Video Tutorial – Calculating Expected Counts in Contingency Tables Using Marginal Proportions and Marginal Totals

A common task in statistics and biostatistics is performing hypothesis tests of independence between 2 categorical random variables.  The data for such tests are best organized in contingency tables, which allow expected counts to be calculated easily.  In this video tutorial in my Youtube channel, I demonstrate how to calculate expected counts using marginal proportions […]

## Variance of the Average of a Sequence

July 8, 2014
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$\{Y_1,\cdots,Y_n\}$

In the case where  are i.i.d. random variables, then Now, what if  are identically distributed, but no longer independent. What if we have an autoregressive process? Assume that Then can be written Here, we will express the variance as a function of  and , but it is possible to use also , since, in the context of an , Now, since  we get which can be simplified, since i.e. So, the variance of the mean can be…

## Chillin’ at UseR! 2014

July 8, 2014
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This year’s UseR! conference was held at the University of California in Los Angeles. Despite the great weather and a nearby beach, most of the conference was spent in front of projector screens in 18° c (64° f) rooms because there were so many i...

## The Oracle (8) – let’s go all the way!

July 7, 2014
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This is (may be) the final post in the series dedicated to the prediction of the World Cup results \$-\$ I'll try and actually write another to wrap things up and summarise a few comments, but this will probably be a bit later on. Finally, we've decided ...

## “Bayes Data Analysis – Author Needed”

July 7, 2014
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The following item came in over the Bayes email list: Hi, My name is Jo Fitzpatrick and I work as an Acquisition Editor for Packt Publishing ( www.packtpub.com ). We recently commissioned a book on Bayesian Data Analysis and I’m currently searching for an author to write this book. You need to have good working […] The post “Bayes Data Analysis – Author Needed” appeared first on Statistical Modeling, Causal…

## On deck this week

July 7, 2014
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Mon: “Bayes Data Analysis – Author Needed” Tues: Just wondering Wed: “P.S. Is anyone working on hierarchical survival models?” Thurs: Open-source tools for running online field experiments Fri: Hey—this is a new kind of spam! Sat, Sun:...

## Introduction to R for Life Scientists: Course Materials

July 7, 2014
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Last week I taught a three-hour introduction to R workshop for life scientists at UVA's Health Sciences Library.I broke the workshop into three sections:In the first half hour or so I presented slides giving an overview of R and why R is so awesome. Du...

## An easy way to expand data by using frequencies

July 7, 2014
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A few years ago I blogged about how to expand a data set by using a frequency variable. The DATA step in the article was simple, but the SAS/IML function was somewhat complicated and used a DO loop to expand the data. (Although a reader later showed how to avoid […]

## A Big "Thank You" to the NZAE

July 7, 2014
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I'd like to express my heart-felt thanks to the New Zealand Association of Economists for making me a Distinguished Fellow.The award took place last Thursday evening at the dinner for the 55th Conference of the Association, in Auckland. The award was m...

## Books to Read While the Algae Grow in Your Fur, December 2013

July 7, 2014
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Attention conservation notice: I have no taste. Julia Spencer-Fleming, Through Evil Days Continuation of the long-running series. Pulls off the trick of making domestic troubles, ice storms, and not-very-bright criminals equally threatening. (Previously.) Prudence Shen and Faith Erin Hicks, Nothing Can Possibly Go Wrong Comic-book mind candy: a school story about evil cheerleaders vs. combat robots. Delightful, though I don't usually care for such unalloyed social realism. G. E. R.…

## Books to Read While the Algae Grow in Your Fur, January 2014

July 7, 2014
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Attention conservation notice: I have no taste. William M. Arkin, American Coup Arkin has something to say about the self-perpetuating and dubiously-constitutional national security bureaucracy its dim views of actual democracy, and its apparent day...