Pollsters puzzle over how they got predictions wrong

Pollsters yesterday defended themselves against critics attacking their credibility, academic merit and neutrality after most came up with inaccurate poll results that projected Pheu Thai Party candidate Pongsapat Pongcharoen beating Democrat Sukhumbhand Paribatra.

Most pollsters, except Nida Poll, gave wrong projections for both pre-election and exit polls over who would be the winner in the governor's race.

Bansomdej poll chief Sing Singkachorn also pointed out about error margins, saying according to academic statistics, exit polls carry an error margin, and the exit poll of the Sunday governor election had an error margin of 2 per cent.

In reality, the margin of the scores between Sukhumbhand and Pongsapat was 1.5 per cent.

Blame put on lack of time

He blamed time restrictions as the cause of error, saying the fact that exit polls collected data for only half of the day could result in inaccurate projections.

He said if pollsters used advanced technology so they could collect data longer, they might be able to reduce errors.

Nida poll chief Suwicha Pao-aree said the inaccurate exit poll results was a result of technical errors and not intentional.

First, the pollsters collected data for only the half-day, since they needed time to process the information.

Second, respondents did not give truthful answers because they did not trust the poll. He said this could be solved by avoiding face-to-face surveying and adopting phone-call surveys.

He said to restore public faith, pollsters who made wrong projections must review their methods and find out what went wrong.

Bangkok poll chief Kittisak Promrat defended his agency's neutrality and the academic merit of its polls during the Bangkok governor's race.

He said there were several factors that affected the accuracy of the poll, from the current political division to different cultures and norms.

He said he noticed that Pheu Thai Party supporters were more confident in expressing their political opinions, while the Democrat supporters were not so expressive.

Errors to be analysed

He said he would call a meeting of academics and lecturers at the Bangkok University to analyse any errors and consider whether exit polls were suitable with the Bangkok governor's election and national elections - or not.

Abac Poll chief Noppadon Kannikar said his agency did not need to overhaul the way it has been conducting polls, because it had followed correct procedures.

He blamed the media, saying they failed to report error margins that pollsters indicate in every poll.

Abac Poll didn't take an exit poll but he said the errors in the survey could result from two factors: errors caused by not choosing correct samples or respondents, and errors caused by respondents not giving truthful answers.