Here’s question 2 of our exam: 2. A multiple-choice test item has four options. Assume that a student taking this question either knows the answer or does a pure guess. A random sample of 100 students take the item. 60% get it correct. Give an estimate and 95% confidence interval for the percentage in the […]

## Question 1 of our Applied Regression final exam

As promised, it’s time to go over the final exam of our applied regression class. It was an in-class exam, 3 hours for 15 questions. Here’s the first question on the test: 1. A randomized experiment is performed within a survey. 1000 people are contacted. Half the people contacted are promised a $5 incentive to […]

## New! from Bales/Pourzanjani/Vehtari/Petzold: Selecting the Metric in Hamiltonian Monte Carlo

Ben Bales, Arya Pourzanjani, Aki Vehtari, and Linda Petzold write: We present a selection criterion for the Euclidean metric adapted during warmup in a Hamiltonian Monte Carlo sampler that makes it possible for a sampler to automatically pick the metric based on the model and the availability of warmup draws. Additionally, we present a new […]

## “Data is Personal” and the maturing of the literature on statistical graphics

Traditionally there have been five ways to write about statistical graphics: 1. Exhortations to look at your data, make graphs, do visualizations and not just blindly follow statistical procedures. 2. Criticisms and suggested improvements for graphs, both general (pie-charts! double y-axes! colors! labels!) and specific. 3. Instruction and examples of how to make effective graphs […]

## Why edit a journal? More generally, how to contribute to scientific discussion?

The other day I wrote: Journal editing is a volunteer job, and people sign up for it because they want to publish exciting new work, or maybe because they enjoy the power trip, or maybe out of a sense of duty—but, in any case, they typically aren’t in it for the controversy. Jon Baron, editor […]

## My (remote) talk this Friday 3pm at the Department of Cognitive Science at UCSD

It was too much to do one more flight so I’ll do this one in (nearly) carbon-free style using hangout or skype. It’s 3pm Pacific time in CSB (Cognitive Science Building) 003 at the University of California, San Diego. This is what they asked for in the invite: Our Friday afternoon COGS200 series has been […]

## Concurve plots consonance curves, p-value functions, and S-value functions

Andrew Vigotsky writes: Now that abandoning significance and embracing uncertainty is in the air, we think this package, which runs in R or Stata, may be of interest to both you and your readers. Concurve plots consonance curves, p-value functions, and S-value functions to allow readers and researchers to get a better feel of the […]

## Let’s publish everything.

The other day someone pointed me to this article by James Kaufman and Vlad Glǎveanu in a psychology journal which begins: How does the current replication crisis, along with other recent psychological trends, affect scientific creativity? To answer this question, we consider current debates regarding replication through the lenses of creativity research and theory. Both […]

## What pieces do chess grandmasters move, and when?

The above image, from T. J. Mahr, is a cleaned-up version of this graph: which in turn is a slight improvement on a graph posted by Dan Goldstein (with R code!) which came from Ashton Anderson. The original, looks like this: This is just fine, but I had a few changes to make. I thought […]

## They’re working for the clampdown

This is just disgraceful: powerful academics using their influence to suppress (“clamp down on”) dissent. They call us terrorists, they lie about us in their journals, and they plot to clamp down on us. I can’t say at this point that I’m surprised to see this latest, but it saddens and angers me nonetheless to […]

## Crystallography Corner: The result is difficult to reproduce, but the result is still valid.

Joel Bernstein writes: I just finished reading your oped article on reproducibility in science. As an experimental scientist – more precisely a chemical crystallographer – I have had to deal with this kind of situation a number of times, and at least two examples may serve as the possible exceptions to your rules. One of […]

## Donald J. Trump and Robert E. Lee

The other day the president made some news by praising Civil War general Robert E. Lee, and it struck me that Trump and Lee had a certain amount in common. Not in their personalities, but in their situations. Lee could’ve fought on the Union side in the Civil War. Or he could’ve saved a couple […]

## John Le Carre is good at integrating thought and action

I was reading a couple old Le Carre spy novels. They have their strong points and their weak points; I’m not gonna claim that Le Carre is a great writer. He’s no George Orwell or Graham Greene. (This review by the great Clive James nails Le Carre perfectly.) But I did notice one thing Le […]

## Pushing the guy in front of the trolley

So. I was reading the London Review of Books the other day and came across this passage by the philosopher Kieran Setiya: Some of the most striking discoveries of experimental philosophers concern the extent of our own personal inconsistencies . . . how we respond to the trolley problem is affected by the details of […]

## Going beyond the rainbow color scheme for statistical graphics

Yesterday in our discussion of easy ways to improve your graphs, a commenter wrote: I recently read and enjoyed several articles about alternatives to the rainbow color palette. I particularly like the sections where they show how each color scheme looks under different forms of color-blindness and/or in black and white. Here’s a couple of […]

## (from Yair): What Happened in the 2018 Election

Yair writes: Immediately following the 2018 election, we published an analysis of demographic voting patterns, showing our best estimates of what happened in the election and putting it into context compared to 2016 and 2014. . . . Since then, we’ve collected much more data — precinct results from more states and, importantly, individual-level vote history records […]

## What are some common but easily avoidable graphical mistakes?

John Kastellec writes: I was thinking about writing a short paper aimed at getting political scientists to not make some common but easily avoidable graphical mistakes. I’ve come up with the following list of such mistakes. I was just wondering if any others immediately came to mind? – Label lines directly – Make labels big […]

## Neural nets vs. regression models

Eliot Johnson writes: I have a question concerning papers comparing two broad domains of modeling: neural nets and statistical models. Both terms are catch-alls, within each of which there are, quite obviously, multiple subdomains. For instance, NNs could include ML, DL, AI, and so on. While statistical models should include panel data, time series, hierarchical […]

## Abortion attitudes: The polarization is among richer, more educated whites

Abortion has been in the news lately. A journalist asked me something about abortion attitudes and I pointed to a post from a few years ago about partisan polarization on abortion. Also this with John Sides on why abortion consensus is unlikely. That was back in 2009, and consensus doesn’t seem any more likely today. […]