Mark Palko points to this report and writes: Putting aside my concerns with the “additional years of learning” metric (and I have a lot of them), I have the feeling that there’s something strange here or i’m missing something obvious. That jump from 3-year impact to 4-year seems excessive. The press release links to a […]

**Teaching**category.

## Regression: What’s it all about? [Bayesian and otherwise]

Regression: What’s it all about? Regression plays three different roles in applied statistics: 1. A specification of the conditional expectation of y given x; 2. A generative model of the world; 3. A method for adjusting data to generalize from sample to population, or to perform causal inferences. We could also include prediction, but I […]

## Define first, prove later

This post by John Cook features a quote form a book “Calculus on Manifolds,” by Michael Spivak which I think was the textbook for a course I took in college where we learned how to prove Stokes’s theorem, which is something in multivariable calculus involving the divergence and that thing that you get where you […]

## New time unit needed!

We need a time unit that’s bigger than a minute but smaller than an hour. I thought of it when writing this comment in which I referred to “2100 valuable minutes of classroom time” during the semester (that’s 75 minutes per class, twice a week, for 14 weeks). A minute of class time is pretty […]

## Stock-and-flow and other concepts that are important in statistical modeling but typically don’t get taught to statisticians

Bill Harris writes: You’ve written about causality somewhat often, and you, along with perhaps everyone who has done anything with statistics, have written that “correlation is not causation.” When you say that correlation is not causation, you seem to be pointing out cases where correlation exists but causality does not. While that’s important, there’s another […]

## “A small but growing collection of studies suggest X” . . . huh?

Lee Beck writes: I’m curious if you have any thoughts on the statistical meaning of sentences like “a small but growing collection of studies suggest [X].” That exact wording comes from this piece in the New Yorker, but I think it’s the sort of expression you often see in science journalism (“small but mounting”, “small […]

## “Academics should be made accountable for exaggerations in press releases about their own work”

Fernando Martel Garcia points me to this news article by Ben Goldacre: For anyone with medical training, mainstream media coverage of science can be an uncomfortable read. It is common to find correlational findings misrepresented as denoting causation, for example, or findings in animal studies confidently exaggerated to make claims about treatment for humans. But […]

## Statistical Significance – Significant Problem?

John Carlin, who’s collaborated on some of my recent work on Type S and Type M errors, prepared this presentation for a clinical audience. It might be of interest to some of you. The ideas and some of the examples should be familiar to regular readers of this blog, but it could be useful to […]

## “Peer assessment enhances student learning”

Dennis Sun, Naftali Harris, Guenther Walther, and Michael Baiocchi write: Peer assessment has received attention lately as a way of providing personalized feedback that scales to large classes. . . . By conducting a randomized controlled trial in an introductory statistics class, we provide evidence that peer assessment causes significant gains in student achievement. The […]

## Discussion with Steven Pinker connecting cognitive psychology research to the difficulties of writing

Following up on my discussion of Steven Pinker’s writing advice, Pinker and I had an email exchange that cleared up some issues and raised some new ones. In particular, Pinker made a connection between the difficulty of writing and some research findings in cognitive psychology. I think this connection is really cool—I’ve been thinking and […]

## Why I keep talking about “generalizing from sample to population”

Someone publishes some claim, some statistical comparison with “p less than .05” attached to it. My response is: OK, you see this pattern in the sample. Do you think it holds in the population? Why do I ask this? Why don’t I ask the more standard question: Do you really think this result is statistically […]

## Documenting a class-participation activity

Tian Zheng implemented my candies demo using Legos: Also lots of details on the results. The point here is not exactly what happened (but, yes, the demo did work) but rather the idea that you can use photos and graphs to document what worked in class. We should be able to do this sort of […]

## Six quick tips to improve your regression modeling

It’s Appendix A of ARM: A.1. Fit many models Think of a series of models, starting with the too-simple and continuing through to the hopelessly messy. Generally it’s a good idea to start simple. Or start complex if you’d like, but prepare to quickly drop things out and move to the simpler model to help […]

## First day of class update

I got to class on time. The class went ok but I spent too much time talking, which is what happens when I don’t put a lot of effort ahead of time into making sure I don’t spend too much time talking. My first-day-of-class activity was ok but I think I needed another activity for […]

## Just in case

Hi, R. Could you please prepare 50 handouts of the attached draft course plan (2-sided printing is fine) to hand out to students? I prefer to do this online but it sounds like there’s some difficulty with that, so we can do handouts on this first day of class. Also: My Amtrak is rescheduled and […]

## The (hypothetical) phase diagram of a statistical or computational method

So here’s the deal. You have a new idea, call it method C, and you try it out on problems X, Y, and Z and it works well—it destroys the existing methods A and B. And then you publish a paper with the pithy title, Method C Wins. And, hey, since we’re fantasizing here anyway, […]

## Tell me what you don’t know

We’ll ask an expert, or even a student, to “tell me what you know” about some topic. But now I’m thinking it makes more sense to ask people to tell us what they don’t know. Why? Consider your understanding of a particular topic to be divided into three parts: 1. What you know. 2. What […]

## “What then should we teach about hypothesis testing?”

Someone who wishes to remain anonymous writes in: Last week, I was looking forward to a blog post titled “Why continue to teach and use hypothesis testing?” I presume that this scheduled post merely became preempted by more timely posts. But I am still interested in reading the exchange that will follow. My feeling is […]

## Plans for reboot of Statistical Communication class

At the end of my course on Statistical Communication and Graphics last semester, I enlisted some of the students to help plan for the new version of the course (which starts next week). I took a bunch of notes on the blackboard and then a student took pictures for me. I had the idea that […]

## Workshop on science communication for graduate students

Nathan Sanders writes: