In an interview with the BBC on his new book ‘The Signal and the Noise: why so many predictions fail, but some don’t” - Nate Silver suggests that there is a big gap between what we think we know in politics and what we actually do know.
It is easier, he says, to predict the outcome of baseball than a presidential election as there is a lot more data available on baseball (162 games are played every year) than there is for an event which only happens every 4 years. In elections, we are trying to make inferences about what will happen in the future based on a small amount of historical data. Outcomes are inferred from various sources of data including factors such as the state of the economy and levels of unemployment at the time of the election (the assumption is usually that there is a direct relationship between these and election results – invariably, not the case in US elections).
Today, there is more data than ever to draw on to predict election outcomes but “in some ways having more data can get you into more trouble if you don’t know what to do with it”.
There’s a wider point about our knowledge gap when it comes to politics. Baseball apart, there are few occasions when data is quite so abundant and the public’s interest in the information in data stronger than during an election. But how well do we grasp the information in data ? How well-equipped are we as voters to handle the ‘noise’ …the cacophony of data we experience ? Do we scrutinise the statistics in manifestos and in the content of pre-election ‘fact-flinging’ debates?. How good are the media at reporting that data?
And politicians’ ‘knowledge gap?. how often are candidates really comparing like with like? how often do they exaggerate numbers, how much real data underpins the big promises they make? and then how evidence-informed is the subsequent media coverage?
Perhaps, we should then ask ourselves how much impact the ability of candidates to use statistics accurately and appropriately in the run-up to an election has on the final election results?. Few would disagree that evidence-informed debate and policy-making should be the norm in parliaments everywhere, let’s not overlook the need for evidence-informed electioneering too.