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 […]

**Teaching**category.

## 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 […]

## My course on Statistical Communication and Graphics

We will study and practice many different aspects of statistical communication, including graphing data and fitted models, programming in Rrrrrrrr, writing for specialized and general audiences, lecturing, working with students and colleagues, and combining words and pictures in different ways. You learn by doing: each week we have two classes that are full of student […]

## I didn’t say that! Part 2

Uh oh, this is getting kinda embarrassing. The Garden of Forking Paths paper, by Eric Loken and myself, just appeared in American Scientist. Here’s our manuscript version (“The garden of forking paths: Why multiple comparisons can be a problem, even when there is no ‘fishing expedition’ or ‘p-hacking’ and the research hypothesis was posited ahead […]

## In defense of stories and classroom activities, from a resubmission letter from 1999

I was going through my files looking for some old data (which I still haven’t found!) and came across a letter from 1999 accompanying the submission of a revision of this article with Glickman. Here’s a part of the letter, a response to some questions of one of the reviewers: With regard to the comment […]

## Are Ivy League schools overrated?

I won’t actually answer the above question, as I am offering neither a rating of these schools nor a measure of how others rate them (which would be necessary to calibrate the “overrated” claim). What I am doing is responding to an email from Mark Palko, who wrote: I [Palko] am in broad agreement with […]