Imagine British Prime Minister Tony Blair's confusion on picking up the newspapers on Monday, June 2. The conservative Daily Telegraph ran a headline "Half of Voters Feel Misled." Underneath, was a report that a YouGov poll shows that 44% of those surveyed think he has deceived them about Iraq's possession of weapons of mass destruction (WMD).
That's not quite half; but never mind. The left-wing Guardian newspaper of the same day begged to differ: 63% of people polled by -- you guessed it, YouGov -- believe he misled them over weapons of mass destruction.
Confused? No doubt so was the prime minister. Does he have to convince 44% or 63% of the public? Since this suggests a 19 percentage point margin of error, is it possible that even more, or fewer, are feeling misled? As a leader who has been accused of being the master of spin by the press, he could be forgiven for asking: who's spinning whom?
London School of Economics Visiting Professor Robert M. Worcester, chairman of the polling agency Mori, explains how the question can tip the answer. Asking a question in the positive, for example "Do you agree that the death penalty should be reintroduced for a convicted child rapist and murderer who while trying to escape killed a prison guard?" normally adds five to 10 points to the response, says Mr.
YouGov posed the following question for the Daily Telegraph in the poll the paper commissioned: "Before the war, President Bush and Tony Blair sought to justify taking military action on the grounds that Saddam Hussein possessed WMD. When they said that, do you believe they were saying what they believed to be true or were they simply trying to justify the war even though they did not actually believe Iraq possessed WMDs?" A majority of 51% said the WMD claims were what the government believed to be true. But 44% surmised that the leaders were simply trying to justify their decision to go to war.
The Mail on Sunday put their question somewhat differently. They asked, "Do you feel that Tony Blair misled the British public on Iraq's possession of WMD?" They then offered four possible answers: Did mislead but not deliberately (36%), deliberately misled (27%), did not mislead (29%), don't know (8%).
So the Daily Mail's poll can be used to show either 65% believed that Mr. Blair acted honorably in that he believed his own arguments -- good for Mr. Blair -- or that 63% believe that Mr. Blair misled them -- bad for Mr. Blair. This helps explain why the Guardian, given a choice of quoting from either poll, chose to use the Daily Mail poll in its story noted above.
But as Peter Kellner, chairman of YouGov acknowledged in a phone interview, those who answered in the Mail poll that Mr. Blair misled them but not deliberately probably would have opted for the first alternative in the Telegraph poll, which put the question in a more positive light. According to Mr. Kellner, the newspapers are themselves involved in formulating the questions and choices in the YouGov polls. Is it surprising then that the Guardian, a newspaper that opposed the war, would "discover" such intense distrust of the prime minister? Prof. Worcester said he insists that MORI alone set the questions and that the full question be published with the responses.
Vacillating, confusing or just plain wrong predictions are often the only consistency in the polling business -- and it doesn't seem to matter in which country the polls are conducted. Opinion polls before the French election famously left voters believing Lionel Jospin would be facing Jacques Chirac in the second round. This caused many voters to stay at home, leaving Mr. Jospin to be knocked out in the first round.
What a difference a few words can make. As David Moore, stating the obvious, said in 1996 when he was the vice president of the Gallup Poll, polls "are very much influenced by the polling process itself."
A national poll from 1985 in the U.S. offered a classic example: When asked if the country was spending enough on "welfare," 19% agreed it was not. When the question was rephrased containing the phrase "assistance to the poor" instead of "welfare," 63% said the government was not spending enough. Small difference, big change.
More art than science, the vagaries of polling leave opinion surveys open to manipulation -- not least by the newspapers that commission them. It is quite likely that the lack of a major WMD discovery has damaged Mr. Blair's credibility. But it is too early to say how much, and even that could depend on which paper you read.