Northern Ireland

Poll results may vary in a science that is far from exact

Elections can throw up results that don't fit with our expectations. Picture by Rui Vieira/PA Wire
Elections can throw up results that don't fit with our expectations. Picture by Rui Vieira/PA Wire Elections can throw up results that don't fit with our expectations. Picture by Rui Vieira/PA Wire

If politicians could request one super power it would surely be to know exactly what the public is thinking. In the absence of such magical insights, however, politicians, like market researchers, are reliant on surveys, or what are known in the political sphere as opinion polls. 

Ideally canvassing a random sample that is big enough to be representative of the overall population, such research aims to accurately reflect public opinion and political preferences at a particular time. Compared longitudinally, ie over time, these snapshots can identify trends and transformations in attitudes.

Ipsos MORI, YouGov, and Red C in the Republic are among the most reliable polling organisations and therefore the most respected. Such exercises are expensive and, even for the seasoned pollsters, never entirely foolproof. Huge resources are required to conduct surveys that are scientifically rigorous, while there's always the possibility that the person being interviewed isn't telling the truth or exaggerates their opinion in a performative manner.

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The way questions are phrased can also influence the answer, while the respondent may be asked to offer an opinion on an issue of which they have no knowledge or considered viewpoint. Surveys conducted at the same time and addressing the same issues may therefore produce different outcomes. Each poll has a margin of error, expressed in percentage terms. The larger the margin of error, the less confident we can be in the results. 

Most if not all surveys throw up outliers and statistics that appear at variance with common sense but even in official elections, as in life, there are quirks and results that don't fit with our expectations.

On rare occasions opinion polls can be spot on but they will never be completely accurate. The results should therefore be taken with a small pinch of salt and some qualification. Yet if conducted using recognised methodology and a representative sample, the results should reflect trends and people's overall tendencies and preferences. These may not always be to your liking – but don't shoot the messenger.

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