Changes

==History of Polling==

==History of Polling==

The first known example of an opinion poll was a local straw vote conducted by a newspaper ''The Harrisburg Pennsylvanian'' in 1824; it showed [[Andrew Jackson]] leading [[John Quincy Adams]] by 335 votes to 169 in the contest for the presidency. Such straw votes—unweighted and unscientific— gradually became more popular; but they remained local, usually city-wide phenomena. In 1916, the large-circulation U.S. magazine ''[[Literary Digest]]'' embarked on a national survey (partly as a circulation-raising exercise) and correctly predicted Woodrow Wilson's election as president. Mailing out millions of postcards and simply counting the returns, the ''Digest'' correctly called the following four presidential elections.

The first known example of an opinion poll was a local straw vote conducted by a newspaper ''The Harrisburg Pennsylvanian'' in 1824; it showed [[Andrew Jackson]] leading [[John Quincy Adams]] by 335 votes to 169 in the contest for the presidency. Such straw votes—unweighted and unscientific— gradually became more popular; but they remained local, usually citywide phenomena. In 1916, the large-circulation U.S. magazine ''[[Literary Digest]]'' embarked on a national survey (partly as a circulation-raising exercise) and correctly predicted Woodrow Wilson's election as president. Mailing out millions of postcards and simply counting the returns, the ''Digest'' correctly called the following four presidential elections.

In 1936, however, the ''Digest'' came unstuck. Its 2.3 million "voters" constituted a huge sample; however they were generally more affluent Americans who tended to have Republican sympathies. The ''Literary Digest'' saw the bias but did not know how to correct it. The week before election day, it reported that [[Alf Landon]] was far ahead of Franklin D. Roosevelt. At the same time, [[George Gallup]] conducted a far smaller, but more scientifically-based survey, in which he polled a demographically representative sample. Gallup correctly predicted Roosevelt's landslide victory. The ''Literary Digest'' went out of business soon afterwards, while the polling industry started to take off .

In 1936, however, the ''Digest'' came unstuck. Its 2.3 million "voters" constituted a huge sample; however they were generally more affluent Americans who tended to have Republican sympathies. The ''Literary Digest'' saw the bias but did not know how to correct it. The week before election day, it reported that [[Alf Landon]] was far ahead of Franklin D. Roosevelt. At the same time, [[George Gallup]] conducted a far smaller, but more scientifically-based survey, in which he polled a demographically representative sample. Gallup correctly predicted Roosevelt's landslide victory. The ''Literary Digest'' went out of business soon afterwards, while the polling industry started to take off .

By providing information about voting intentions, opinion polls can sometimes influence the behaviour of electors. The various theories about how this happens can be split up into two groups: bandwagon/underdog effects, and strategic ('tactical') voting.

By providing information about voting intentions, opinion polls can sometimes influence the behaviour of electors. The various theories about how this happens can be split up into two groups: bandwagon/underdog effects, and strategic ('tactical') voting.

A [[Bandwagon effect]] occurs when the poll prompts voters to back the candidate shown to be winning in the poll. The idea that voters are susceptible to such effects is old, stemming at least from 1884; Safire (1993: 43) reported that it was first used in a political cartoon in the magazine Puck in that year. It has also remained persistent in spite of a lack of empirical corroberation until the late 20th century. [[George Gallup]] spent much effort in vain trying to discredit this theory in his time by presenting empirical research. A recent meta-study of scientific research on this topic indicates that from the 1980s onward the Bandwagon effect is found more often by researchers (Irwin & van Holsteyn 2000).

A [[Bandwagon effect]] occurs when the poll prompts voters to back the candidate shown to be winning in the poll. The idea that voters are susceptible to such effects is old, stemming at least from 1884; Safire (1993: 43) reported that it was first used in a political cartoon in the magazine Puck in that year. It has also remained persistent in spite of a lack of empirical corroberation until the late 20th century. George Gallup spent much effort in vain trying to discredit this theory in his time by presenting empirical research. A recent meta-study of scientific research on this topic indicates that from the 1980s onward the Bandwagon effect is found more often by researchers (Irwin & van Holsteyn 2000).

The opposite of the bandwagon effect is the [[Underdog effect]]. It is often mentioned in the media. This occurs when people vote, out of sympathy, for the party perceived to be 'losing' the elections. There is less empirical evidence for the existence of this effect than there is for the existence of the Bandwagon effect (Irwin & van Holsteyn 2000).  

The opposite of the bandwagon effect is the [[Underdog effect]]. It is often mentioned in the media. This occurs when people vote, out of sympathy, for the party perceived to be 'losing' the elections. There is less empirical evidence for the existence of this effect than there is for the existence of the Bandwagon effect (Irwin & van Holsteyn 2000).