Noted psychology researchers and methods skeptics Leif Nelson and Uri Simonsohn write: A recent Psych Science (.pdf) paper found that sports teams can perform worse when they have too much talent. For example, in Study 3 they found that NBA teams with a higher percentage of talented players win more games, but that teams with […]

**Teaching**category.

## I (almost and inadvertently) followed Dan Kahan’s principles in my class today, and that was a good thing (would’ve even been more of a good thing had I realized what I was doing and done it better, but I think I *will* do better in the future, which has already happened by the time you read this; remember, the blog is on a nearly 2-month lag)

As you might recall, the Elizabeth K. Dollard Professor says that to explain a concept to an unbeliever, explain it conditionally. For example, if you want to talk evolution with a religious fundamentalist, don’t try to convince him or her that evolution is true; instead preface each explanation with, “According to the theory of evolution […]

## Princeton Abandons Grade Deflation Plan . . .

. . . and Kaiser Fung is unhappy. In a post entitled, “Princeton’s loss of nerve,” Kaiser writes: This development is highly regrettable, and a failure of leadership. (The new policy leaves it to individual departments to do whatever they want.) The recent Alumni publication has two articles about this topic, one penned by President […]

## “Patchwriting” is a Wegmanesque abomination but maybe there’s something similar that could be helpful?

Reading Thomas Basbøll’s blog I came across a concept I’d not previously heard about, “patchwriting,” which is defined as “copying from a source text and deleting some words, altering grammatical structures, or plugging in one synonym for another.” (See here for further discussion.) As Basbøll writes, this is simply a variant of plagiarism, indeed it’s […]

## Solution to the sample-allocation problem

See this recent post for background. Here’s the question: You are designing an experiment where you are estimating a linear dose-response pattern with a dose that x can take on the values 1, 2, 3, and the response is continuous. Suppose that there is no systematic error and that the measurement variance is proportional to x. You […]

## Solution to the problem on the distribution of p-values

See this recent post for background. Here’s the question: It is sometimes said that the p-value is uniformly distributed if the null hypothesis is true. Give two different reasons why this statement is not in general true. The problem is with real examples, not just toy examples, so your reasons should not involve degenerate situations such as […]

## Solution to the helicopter design problem

See yesterday’s post for background. Here’s the question: In the helicopter activity, pairs of students design paper ”helicopters” and compete to create the copter that takes longest to reach the ground when dropped from a fixed height. The two parameters of the helicopter, a and b, correspond to the length of certain cuts in the […]

## Some questions from our Ph.D. statistics qualifying exam

In the in-class applied statistics qualifying exam, students had 4 hours to do 6 problems. Here were the 3 problems I submitted: In the helicopter activity, pairs of students design paper ”helicopters” and compete to create the copter that takes longest to reach the ground when dropped from a fixed height. The two parameters of the […]

## Three ways to present a probability forecast, and I only like one of them

To the nearest 10%: To the nearest 1%: To the nearest 0.1%: I think the National Weather Service knows what they’re doing on this one.

## Statistical Communication and Graphics Manifesto

Statistical communication includes graphing data and fitted models, programming, writing for specialized and general audiences, lecturing, working with students, and combining words and pictures in different ways. The common theme of all these interactions is that we need to consider our statistical tools in the context of our goals. Communication is not just about conveying […]