Just to shake things up a bit, here's a post on a polling controversy from 1936.
Earlier this week, Investor's Business Daily ran a fascinating biographical profile of Dr. George Gallup, the founder of the Gallup poll and, for all practical purposes, the founder of political polling as we know it. The article includes some details that I had not heard before, such as the fact that Gallup's first application of market research to political campaigns was on behalf of his mother-in-law's successful campaign for secretary of state in Iowa. It is well worth a click.
That said, I want pass along some interesting commentary about the story posted earlier today on the members-only listserv of the American Association
for Public Opinion Research (and quoted with permission). The article opens by revisiting Gallup's bold prediction that Franklin Roosevelt would win reelection in 1936 in the face of well known polling by the Literary Digest magazine showing a big lead for Republican Alf Landon. The IBD story is correct that Roosevelt's ultimate victory "led to the death of the Literary Digest" and helped make Gallup "a household name." According to statistical consultant Dominic Lusinchi, however, the story "perpetuates two myths" about the infamous Literary Digest polls:
1) That Gallup "predicted" that the Digest poll would forecast a Landon victory and
2) That the Digest failed because its sampling frame was "skewed ... to the wealthy".
Myth 1: In a July 12, 1936 syndicated column "America Speaks", Gallup wrote:"If the Literary Digest were conducting its poll at the present time [my emphasis], following its usual procedure, Landon would be shown in the lead." (Wash. Post, Section III, p.2, col. 7, Sunday, July 12, 1936) It's one thing to say "at the present time" and another to say "when the Digest presents its final results".... It is only after the Digest poll debacle that this story morphed into a "prediction". What Gallup really predicted, at that time (7/12/1936), was that the election was going to be a close one: the title of his column "1936 Election Seen As Closest in Years".
Myth 2: The Digest poll failed because its original sample, composed mainly of telephone and/or car owners, was irretrievably skewed against Roosevelt. A close analysis of a May 1937 Gallup (yes, Gallup!) poll, which asked its respondents if they had received and returned a Digest ballot card, shows that the principal cause of the Digest poll's failure was non-response bias. As Peverill Squire wrote in POQ (vol. 52, 1988, p.125), "if all those who were polled had responded, the magazine would have, at least, correctly predicted Roosevelt the winner." In fact, its prediction (my analysis) would have been as good if not better than Gallup's - he was off by nearly 7 points of the two-party vote.
Why Gallup never referred to this May 1937 poll done by his organization when he commented (many many times) on the failure of the Digest poll...?
Well that would take too long... got to get back to work.
Thanks Dominic!
Update: These comments provoked a lengthy exchange with another knowledgeable AAPOR member who takes with Dominic Lusinchi's version of the history.