6. A survey of New York City residents is performed using cluster sampling. The design effect is 3.0. From the survey, the estimated proportion who prefer the Mets to the Yankees is 0.42 with a standard error of 0.05. How many people were in the sample? Solution to question 5 From yesterday: 5. Which of [...]
Archive of entries posted by
Wikipedia author confronts Ed Wegman
Wegman: “It’s not reprinted 100 percent like you had it.” Wikipedia guy: “No, you added another paragraph at the end and you changed the headline. . . . You even copied the typos that I’ve corrected on my website. It was taken verbatim and reprinted in your paper.” The original author got a check for [...]
Question 5 of my final exam for Design and Analysis of Sample Surveys
5. Which of the following better describes changes in public opinion on most issues? (Choose only one.) (a) Dynamic stability: On any given issue, average opinion remains stable but liberals and conservatives move back and forth in opposite directions (the “accordion model”) (b) Uniform swing: Average opinion on an issue can move but the liberals [...]
A statistical research project: Weeding out the fraudulent citations
John Mashey points me to a blog post by Phil Davis on “the emergence of a citation cartel.” Davis tells the story:
Question 4 of my final exam for Design and Analysis of Sample Surveys
4. Researchers have found that survey respondents overreport church attendance. Thus, naive estimates from surveys overstate the percentage of Americans who attend church regularly. Does this have a large impact on estimates of time trends in religious attendance? Solution to question 3 From yesterday: 3. We discussed in class the best currently available method for [...]
I hate to get all Gerd Gigerenzer on you here, but . . .
Jonathan Cantor points me to an opinion piece by psychologist Reid Hastie, “Our Gift for Good Stories Blinds Us to the Truth.” I have mixed feelings about Hastie’s article. On one hand I do think his point is important. It’s not new to me, but presumably it’s new to many readers of bloomberg.com. I like [...]
Question 3 of my final exam for Design and Analysis of Sample Surveys
3. We discussed in class the best currently available method for estimating the proportion of military servicemembers who are gay. What is that method? (Recall the problems with the direct approach: there is no simple way to survey servicemembers at random, nor is it likely that they would answer such a question honestly.) Solution to [...]
Stolen jokes
Fun stories here (from Kliph Nesteroff, link from Mark Palko).
More on Uncle Woody
Here. See also here. He did Wacky Packs!
Question 2 of my final exam for Design and Analysis of Sample Surveys
2. Which of the following are useful goals in a pilot study? (Indicate all that apply.) (a) You can search for statistical significance, then from that decide what to look for in a confirmatory analysis of your full dataset. (b) You can see if you find statistical significance in a pre-chosen comparison of interest. (c) [...]
black and Black, white and White
I’ve always thought it looked strange to see people referred to in print as Black or White rather than black or white. For example consider this sentence: “A black guy was walking down the street and he saw a bunch of white guys standing around.” That looks fine, whereas “A Black guy was walking down [...]
Question 1 of my final exam for Design and Analysis of Sample Surveys
1. Suppose that, in a survey of 1000 people in a state, 400 say they voted in a recent primary election. Actually, though, the voter turnout was only 30%. Give an estimate of the probability that a nonvoter will falsely state that he or she voted. (Assume that all voters honestly report that they voted.) [...]
Are our referencing errors undermining our scholarship and credibility? The case of expatriate failure rates
Thomas Basbøll points to this ten-year-old article from Anne-Wil Harzing on the consequences of sloppy citations. Harzing tells the story of an unsupported claim that is contradicted by published data but has been presented as fact in a particular area of the academic literature. She writes that “high expatriate failure rates [with "expatriate failure" defined [...]
My final exam for Design and Analysis of Sample Surveys
We had 28 class periods, so I wrote an exam with an approximate correspondence of one question per class. Rather than dumping the exam in your lap all at once, I’ll post the questions once per day. Then each day I’ll post the answer to yesterday’s questions. So it will be 29 days in all. [...]
Now that’s what I call a lag!
I received the following email the other day: Dear Dr. Gelman, I am emailing to let you know that your accepted article for Economic Inquiry will be published in print in the forthcoming April 2012 Issue. You will be receiving hard copies of the journal from Wiley-Blackwell for distribution to yourself and the Co Authors. [...]
Varying treatment effects, again
This time from Bernard Fraga and Eitan Hersh. Once you think about it, it’s hard to imagine any nonzero treatment effects that don’t vary. I’m glad to see this area of research becoming more prominent. (Here‘s a discussion of another political science example, also of voter turnout, from a few years ago, from Avi Feller [...]
The first version of my “inference from iterative simulation using parallel sequences” paper!
From August 1990. It was in the form of a note sent to all the people in the statistics group of Bell Labs, where I’d worked that summer. To all: Here’s the abstract of the work I’ve done this summer. It’s stored in the file, /fs5/gelman/abstract.bell, and copies of the Figures 1-3 are on Trevor’s [...]
chartsnthings !
Yair pointed me to this awesome blog of how the NYT people make their graphs. This blows away all other stat graphics blogs (including this one). Lots of examples from mockup to first tries to final version. I recognize a lot of what they’re doing from my own experience. Also from my experience it’s hard [...]
Happy news on happiness; what can we believe?
Sharon Jayson writes: The conventional wisdom that’s developed over the past few decades — based on early research — has said parents are less happy, more depressed and have less-satisfying marriages than their childless counterparts. But now, two new studies presented as part of the Population Association of America’s annual meeting suggest that earlier findings [...]
The hare, the pineapple, and Ed Wegman
Commenters here are occasionally bothered that I spend so much time attacking frauds and plagiarists. See, for example, here and here. Why go on and on about these losers, given that there are more important problems in the world such as war, pestilence, hunger, and graphs where the y-axis doesn’t go all the way down [...]
Lists of Note and Letters of Note
These (from Shaun Usher) are surprisingly good, especially since he appears to come up with new lists and letters pretty regularly. I suppose a lot of them get sent in from readers, but still. Here’s my favorite recent item, a letter sent to the Seattle Bureau of Prohibition in 1931: Dear Sir: My husband is [...]
Picking on Stephen Wolfram
Shalizi. But this one is still my favorite.
Fun with google autocomplete
Aleks points us to this idea of labeling for news.
I’m skeptical about this skeptical article about left-handedness
I was flipping through the paper and noticed an opinion piece by linguist and science writer Rik Smits, “Lefties aren’t special after all”: Few truly insignificant traits receive as much attention as left-handedness. In just the last couple of generations, an orientation once associated with menace has become associated with leadership, creativity, even athletic prowess. [...]
Recently in the sister blog
Culture war: The rules You can only accept capital punishment if you’re willing to have innocent people executed every now and then The politics of America’s increasing economic inequality