The reports in the press this morning ascribing the failure of the polls to predict the last election result to failing to connect with older or busy people don't quite, I think, capture the problems faced by opinion pollsters.
Primarily, the true reason for the failure of the polls must be cost. The cheapest way of carrying out a poll quickly is by telephone, using low paid call-centre staff. The most expensive is to send out 1,000 enumerators to door-knock across the land to get 1,200 opinions. Secondly, time of contact is critical; Labour voters may be expected to be less likely to respond during 'Emmerdale' and Tory voters during the 8pm to 9pm middle class dinner hour. Now often including the 7pm to 8pm Aperitif hour. To those persecuted by PPI calls, a pollster on the phone may simply be an opportunity to vent anger and frustration against a real person by telling them to 'bugger off'. In London, with over 30% single occupancy, and high employment rates, 7pm is the mean time that people open their front door. Answering a ringing phone before you've taken your coat off only to find that it's an opinion pollster also induces rage. Calling after 9pm is a no-no. So with our precious evenings out of reach of the telephone pollsters, one presumes their samples are restricted to the unemployed and bored housewives (if such things exist any more) before 6pm.
I don't think the opinion poll is dead - but probably that the phone poll to house-phones has reached its Dodo stage. Alternatives cost a great deal more. Clients should be prepared to pay if they want more accurate polls.