The Literary Digest was an influential American general interest weekly magazine published by Funk & Wagnalls. Founded by Isaac Kaufmann Funk in 1890, it eventually merged with two similar weekly magazines, Public Opinion and Current Opinion.
Cover of the 19 February 1921 edition of The Literary Digest Beginning with early issues, the emphasis was on opinion articles and an analysis of news events. Established as a weekly newsmagazine, it offered condensations of articles from American, Canadian and European publications. Type-only covers gave way to illustrated covers during the early 1900s. After Isaac Funk's death in 1912, Robert Joseph Cuddihy became the editor.[1] In the 1920s, the covers carried full-color reproductions of famous paintings. By 1927, The Literary Digest climbed to a circulation of over one million. Covers of the final issues displayed various photographic and photo-montage techniques. In 1938, it merged with the Review of Reviews, only to fail soon after. Its subscriber list was bought by Time.[1] A column in The Digest, known as "The Lexicographer's Easy Chair", was produced by Frank Horace Vizetelly.[2] Ewing Galloway was assistant editor at the publication.[3] The Literary Digest is best-remembered today for the circumstances surrounding its demise.
From 1916, it conducted a poll regarding the likely outcome of the quadrennial presidential election. Prior to the 1936 election, the poll had always correctly predicted the winner.
In 1936, the poll concluded that the Republican candidate, Governor Alfred Landon of Kansas, was likely to be the overwhelming winner against incumbent President Franklin Delano Roosevelt.[4] In November, Roosevelt won the election in an unprecedented landslide, winning every state except Maine and Vermont while also winning the popular vote by 24.26%. The magnitude of the magazine's error - 19.54% for the popular vote for Roosevelt v Landon, and even more in some states - destroyed the magazine's credibility, and it folded within 18 months of the election.
In hindsight, the polling techniques employed by the magazine were faulty: although it had polled ten million individuals (of whom 2.27 million responded, an astronomical total for any opinion poll),[5] it had surveyed its own readers first, a group with disposable incomes well above the national average of the time (shown in part by their ability to afford a magazine subscription during the depths of the Great Depression), and two other readily available lists, those of registered automobile owners and that of telephone users, both of which were also wealthier than the average American at the time.
It is also notable that every other poll made at or around this time predicted Roosevelt would defeat Landon, albeit not to the extent that he ultimately did: most of these polls also expected Roosevelt to receive a maximum of 360 electoral votes.
Subsequent research concluded that as expected, this sampling bias was a factor, but non-response bias was the primary source of the error - that is, people who disliked Roosevelt had strong feelings and were more willing to take the time to mail back a response.[6][7] George Gallup's American Institute of Public Opinion achieved national recognition by correctly predicting the result of the 1936 election. Gallup also correctly predicted the (quite different) results of the Literary Digest poll to within 1.1%, using a much smaller sample size of just 50,000, [5] while Gallup's final poll before the election predicted Roosevelt would receive 56% of the popular vote and 481 electoral votes: the official tally saw Roosevelt receive 60.8% and 523.
This debacle led to a considerable refinement of public opinion polling techniques, and later came to be regarded as ushering in the era of modern scientific public opinion research.[8]
Wikimedia Commons has media related to The Literary Digest.
There is more than one way to select a sample badly, and great care is needed in both the design and the practical implementation of a sampling process to avoid biases arising. A sampling plan might be well designed, but if the plan is impractical in the field, the final sample will not be representative: it may be biased. Convenience samplesSome methods of obtaining participants are particularly bad; relying on volunteers is one of them. This can result in strong bias. Often people who volunteer for a sample are more likely to have a vested interest in the topic of the survey than people who don't volunteer. Recently, internet companies have begun recruiting people to join online survey panels; these are groups of people willing to answer online surveys, usually for some pay. When these people sign up for the panel, they do not have knowledge of the topics of the surveys they might be invited to participate in. However, they have agreed to answer surveys for reward, and this makes them a particular subset of the general population, and not a random selection.
Exercise 4 You will often see invitations to participate in surveys on the television and on the internet. An example is an online poll for the magazine Cosmopolitan, which invited readers to take part in a survey with the title 'Do you abuse prescription drugs?'
Problems with the sample frameObtaining a suitable sample frame is important for avoiding biases in the results obtained from a sample chosen from that frame. This can be tricky, as discussed in the previous section; the population of interest might not be static in space or in time. Simply selecting a sample where it is convenient may be logistically easier, but it might not give a fair representation of the population of interest.
In the presidential election held in the United States in 1936, the candidates were the incumbent President Franklin Roosevelt (Democrat) and Alf Landon (Republican). The Literary Digest was a popular and widely read weekly magazine that ran a poll to predict the winner of the presidential race, and had done so correctly from 1920 to 1932. In 1936, The Literary Digest mailed a questionnaire to 10 million people to ask about their voting intentions. This extraordinary number of people included readers of The Literary Digest, registered car owners and people listed in the phone book. In one of the largest surveys ever (although not The Literary Digest's largest), 2.4 million voters replied. The response rate — the percentage of people responding of those invited to participate — was \(\dfrac{2\ 400\ 000}{10\ 000\ 000}\), or 24%. The Literary Digest claimed 'The country will know to within a fraction of one per cent the actual popular vote of forty million.' The prediction that The Literary Digest made based on their survey was that Franklin Roosevelt would receive only 43% of the vote; Landon was predicted to win in a landslide. As you may know, Roosevelt won — he obtained 62% of the vote of around 40 million voters.The failure of The Literary Digest's poll was an embarrassment, and The Literary Digest subsequently went out of business; eventually its subscriber list was bought by Time magazine. Why did The Literary Digest get the result so wrong? One problem was that the sample frame — the set of lists of names from which they recruited voters — was biased. Magazine readers, car club members and telephone subscribers tended to be relatively wealthy, and the wealthy at this time (during the great Depression) tended to be Republican voters. This is an example of a biased sample frame. The large number of people responding to the survey did not guarantee that the result would be accurate. You might also wonder why The Literary Digest failed in 1936 when its reputation had been built on successful predictions of the results of earlier presidential elections. One reason is that economic conditions in the US were in decline, and in 1936 voting patterns related more strongly to economic circumstances than they had in the past. Biases in the sample frame used mattered less in earlier elections.
In 1936, the American Institute of Public Opinion also carried out a poll asking voters about their intentions in the upcoming presidential election. The institute's founder, George Gallup, understood that a very large sample would not necessarily provide an accurate result. Gallup had worked out what kinds of personal characteristics (including state, urban/rural residence, gender, age and income) related to voting patterns, and used these in the design of his sample. He set quotas for the numbers of individuals needed for each type of respondent, so that the number surveyed would reflect the population distribution. Gallup's method of filling quotas is not a random sampling method. On 31 October 1936, Gallup reported the results of his final poll in his syndicated newspaper column 'America Speaks'; he predicted that Roosevelt would win the election with 56% of the vote. This prediction was 6% lower than the actual result, but much closer than The Literary Digest's prediction and, importantly, a correct prediction of a win for Roosevelt. Gallup's result was based on the responses of around 50 000 voters. Why did the American Institute of Public Opinion's poll do better than The Literary Digest's poll? First, they asked about voting patterns in face-to-face interviews as well as by mail; they employed hundreds of interviewers across the country with quotas to fill, and so the survey did not suffer the same biases as The Literary Digest's poll. Second, the intention was to avoid bias in the sampling of individuals to be interviewed, although details about how this was carried out are sketchy.
George Gallup was relatively unknown before the 1936 presidential election. He had studied the polling methods used by The Literary Digest and thought he could do better. Gallup made a bold prediction of The Literary Digest's prediction of the election result before The Literary Digest made its own prediction! Gallup based his claim on a survey of 3000 people who were selected at random from the lists (sample frame) used by The Literary Digest. Gallup used the same method as The Literary Digest to collect information — by mail. Gallup predicted that The Literary Digest would call the result for Landon with Roosevelt obtaining only 44% of the vote. This was only 1% higher than the prediction The Literary Digest made. Gallup got enormous publicity. Why did this American Institute of Public Opinion survey result correspond so well to The Literary Digest's result? The population that Gallup and his colleagues wanted to survey was the population of voters who were to be surveyed by The Literary Digest. For this, they had a very well-defined sample frame: the lists of magazine readers, registered car owners and telephone subscribers. Gallup sampled randomly from this list. Problems with the response rateWhen sampling human populations in particular, the willingness of invited participants to respond to the invitation and participate in the study can be an important issue. Increasingly, targeted potential respondents are unwilling to participate. The response rate is the percentage of targeted potential respondents that actually respond. In sampling from a human population, there are many reasons why a sampled unit might not participate in the study. If the details in the sample frame are incorrect, the individual might not be able to be contacted. Contact details might be correct, but busy individuals may be hard to find. People might refuse to participate for a wide range of reasons: health, ethical issues relating to the study, lack of interest or insufficient time. This is an important issue in human surveys; it can be less problematic in surveys of other entities.
A common criticism of the 1936 Literary Digest poll is the low response rate of 24%. In Gallup's news report on 31 October 1936, where he gave the result of the final pre-election poll by the American Institute of Public Opinion, he stated that 'The number of ballots distributed in the poll was 312 551.' The final sample size for this poll is reported as 'around 50 000' (see the textbook listed in the References section). There is little information available about the response rate for the American Institute of Public Opinion poll. Lawrence E. Benson, an associate of the American Institute of Public Opinion, reported a \(17.3\%\) response rate for the institute's mail surveys in 1936. It seems that the response rate to the American Institute of Public Opinion election poll must have been lower than that for the Literary Digest poll. Gallup would have needed about 75 000 responses for a response rate comparable to that of The Literary Digest. Why is The Literary Digest's response rate so often highlighted as a concern? One reason is that, when there is a poor response rate, there is a potential for non-response bias. We discuss this next. Non-response biasPeople who have been randomly selected to be part of a survey but refuse the invitation to participate can be different from the people who agree to participate. Non-response bias occurs when the people who respond to the survey are different, on average, from those who do not. More generally, the units in a sample that cannot be contacted and the units in the sample that can be contacted may differ in important ways that relate to the purpose of the survey.Often, unfortunately, the possibility for non-response bias is ignored. The lower the response rate, the more scope there is for non-response bias. If a large proportion of a sample fails to respond, having a large sample will not help: the results should be regarded as unreliable.
Exercise 5 Consider carrying out a long-term study of drug and alcohol use in young men, where you select a random sample of boys aged 13 to 16 and intend to follow them up several times into adulthood.
There was a state election in Victoria in late 2010. The Age 
Exercise 6 Consider the 2010 The Age
The response rates for The Literary Digest and the American Institute of Public Opinion's polls of 1936 election were both relatively poor, allowing for the possibility of non-response bias. The purpose of both polls was to provide accurate estimates of the percentage of people voting for Roosevelt and for Landon. The Literary Digest's result was highly inaccurate; the American Institute of Public Opinion's poll was over 6% out. The voters responding to The Literary Digest's invitation to participate, in particular, tended to be Republican (Landon) voters; those who chose not to participate tended to be Democrat voters. Biases in the same direction are likely to have been operating in Gallup's pre-election poll, as his result underestimated the Democrat vote. Scholars still debate the extent to which the spectacular failure of the Literary Digest poll was due to non-response bias versus a biased sample frame. It is likely that both were contributing factors.
Exercise 7 The Literary Digest's presidential poll of 1936 obtained responses from 2 400 000 voters from 10 000 000 sampled. Recall that 43% of the respondents indicated they would vote for Roosevelt.
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Which of the following was a mistake in the literary digest poll of the 1936 presidential election?
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