In his 2004 book, The Wisdom of Crowds, James Surowiecki argues that a random group of independently deciding persons is likely to make predictions better than any single member belonging to that group could have done. Amongst the many anecdotes to buttress his argument, he talks of how the crowd at a county fair accurately guessed the weight of an ox when they averaged the guesses of its individual members (the average was closer to the ox's true weight than the estimates of most crowd members).
I had a glimpse of this when I was a jury member in an Inter B-School Stock Market Contest. The participants received access to the NSE terminal, gleaned it between 945 am and 11 am, at the end of which they predicted the NIFTY points at the closing bell, namely 345 pm. Yes, they were making their prediction 5 hours in advance. The winner would be the one whose prediction came closest to the actual closing points. If you averaged the several predictions of the 27 teams, the number turned out to be the winner!
Armed with this information, I proceeded to check if collectively the exit pollsters came with an outcome closest to the actual result. I picked the case of UP where the BJP swept the polls, Punjab where the Congress had an early Holi, and Goa that saw a hung assembly.
My sense is that pollsters can say whatever they like, but their strike rates in the past few years have been pathetic. There was a time, many years ago when Prannoy Roy predicted to a seat the victory of the DMK in the late 1980s and almost to a seat the Congress tally in 1989. That possibly hooked the country to the idea of exit polls. But over the years with the pollsters making a hash of things, intentionally or otherwise, the idea of poll of polls emerged. And this time around, that too has been hit for a six.
Exit polls can engage us with some tamasha. They would have been valid if your results were to be announced several days after the conclusion of the final phase of polling. Otherwise, it might just as well be that we wait for the real stuff. And in that sense one is terribly happy with the Election Commission for banning opinion polls. Given the divisive polity that we today live in, given the short memory of the public, these opinion polls can have a slant and influence voters. Those who said that voters must have information while they vote should remember that you don’t need information on whom the other person is going to vote for. It’s like copying in the exams.