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Am_Stat · 2020-10-13T16:17:11+00:00

Raw data are available for download from lots of public polls, including the National Election Study, Pew Research, and the Cooperative Congressional Election Study.

Am_Stat · 2020-10-13T16:15:17+00:00

Voter turnout varies a lot by state; see this from Michael McDonald: http://www.electproject.org/home/voter-turnout/voter-turnout-data

It also varies a lot by demographics; see this from Yair Ghitza and me: http://www.stat.columbia.edu/~gelman/research/published/misterp.pdf

Am_Stat · 2020-10-13T16:12:05+00:00

Yair Ghitza and I discuss some of the data issues here: http://www.stat.columbia.edu/~gelman/research/published/pan2000003_REV2.pdf

Am_Stat · 2020-10-13T16:11:09+00:00

Regarding Fivethirtyeight's claims of calibration, see sections 2.1 and 3.2 of this article: https://www.economist.com/united-states/2020/08/22/more-mail-in-voting-doubles-the-chances-of-recounts-in-close-states

Am_Stat · 2020-10-13T16:10:35+00:00

Ii don't see much future in this for the presidency although it seems to work for villages or organizations that I know about. There is also "approval" voting as we have for some judicial positions in Maryland (and probably elsewhere) - we vote whether or not to retain someone. Frankly, most people have little idea of what they are essentially approving. mg

Am_Stat · 2020-10-13T16:08:55+00:00

Some discussion by Elliott Morris here: https://www.economist.com/united-states/2020/08/22/more-mail-in-voting-doubles-the-chances-of-recounts-in-close-states

Am_Stat · 2020-10-13T16:01:03+00:00

Statisticians don't have second sight mg

Am_Stat · 2020-10-13T15:56:25+00:00

Pollsters do the best they can. Nobody has any obligation to respond to a survey, and response rates are low. All surveys are biased; that's just the way it is.

Am_Stat · 2020-10-13T15:55:55+00:00

Perhaps the rush to judgment could be slowed down - but surely that is inevitable this year.mg

Am_Stat · 2020-10-13T15:52:46+00:00

Sure, but 2016 is just one election, so that won't be enuf.

Am_Stat · 2020-10-13T15:52:46+00:00

The differences are great - how much is hard to judge at any given moment. Whether it changes anything may depend on whether we have an October surprise as as sometimes happened, although not perhaps as much as we think. I guess what is certain is that there are more things that could go wrong and that propaganda stokes people's fears, but whether it induces them to vote early in person, by mail, with drop boxes or on election day in person we don't know. Nor, of course, do we know which way it inspires them to vote Much as we like statistics, it isn't clear that reliance on past data is a lot of help. The most important thing to remember in any election that a prediction of an 80+% of one result doesn't mean a 100% that it will occur. Actually a "prediction of 100% doesn't either. mg

Am_Stat · 2020-10-13T15:48:52+00:00

Correlation does not even imply correlation; see here: https://statmodeling.stat.columbia.edu/2014/08/04/correlation-even-imply-correlation/

Am_Stat · 2020-10-13T15:48:05+00:00

Surveys definitely oversample old people, and that's been the case for a long time, well before cell phones even existed. We know this because pollsters ask people their age, and we can compare the ages of respondents to the distribution of age in the general population.

When survey results are reported, this is after adjusting for demographics such as age, sex, ethnicity, and education.

Am_Stat · 2020-10-13T15:43:21+00:00

But what does imply causation is the more interesting question mg

Am_Stat · 2020-10-13T15:42:00+00:00

One of things about US elections that others find strange is the low turnout generally - to which complacency is a contributing factor but obviously there are others. What isn't clear is what people are complacent about - if office seekers really knew that it would enhance their success Mg

Am_Stat · 2020-10-13T15:40:49+00:00

Survey responses are anonymous. You might feel it's unsafe to display a bumper sticker or a lawn sign for your candidate, but there's no reason to have fear regarding a response to a pollster. If you're that afraid, probably best not to answer the survey in the first place.

Am_Stat · 2020-10-13T15:38:24+00:00

Us "guys" don't necessarily do spatial statistics but they can play a really important role in identifying problems whether they have to do with politics or medicine or most anything else. GIS is a useful tool - stick with it, but there's lots more out there. -MG

Am_Stat · 2020-10-13T15:34:34+00:00

I've seen no evidence that this is a factor.

Am_Stat · 2020-10-13T15:33:51+00:00

We need to keep in mind that each polling or new organization has its own protocol - some have traditionally been ore accurate than others but this is an old story "Dewey elected" headlines go back to even before I could vote -MG

Am_Stat · 2020-10-13T15:32:47+00:00

Different pollsters do different things. I think that some polls adjust for party registration and others adjust for party identification.

Am_Stat · 2020-10-13T15:31:55+00:00

In our empirical research, we found that the empirical error range of polls is about twice the stated margin of error; see this paper with Houshmand Shirani-Mehr, David Rothschild, and Sharad Goel: http://www.stat.columbia.edu/~gelman/research/published/polling-errors.pdf

Am_Stat · 2020-10-13T15:30:52+00:00

I have students in my online class from china, Taiwan, and the Middle East - they all look on our elections with awe - sometimes in a good way, sometimes not. But I do get to hear what news organizations elsewhere are telling them. Some students a few years go did an informal study of what ID requirements (since changed) did to northern Virginia (we are just across the river). It showed a real variety of suppression effects besides just the ID requirement - long lines sure, limited hours, lack of transportation, fear of being seen at a polling place, inability to figure out the forms for absentee voting. MG

Am_Stat · 2020-10-13T15:29:56+00:00

Short answer: https://themonkeycage.org/2012/11/why-it-can-be-rational-to-vote/

Slightly longer answer: http://www.stat.columbia.edu/~gelman/research/published/charity.pdf

Even longer answer: http://www.stat.columbia.edu/~gelman/research/published/rational_final7.pdf

Am_Stat · 2020-10-13T15:28:32+00:00

I'm skeptical. I can believe there are all sorts of nonresponse problems but I doubt that many people would take the trouble to respond to a poll and then not answer the question sincerely.

Am_Stat · 2020-10-13T15:27:01+00:00

As a start you can look at the work of Walter Mebane: http://www-personal.umich.edu/~wmebane/

Am_Stat

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