#GE2015 Forecast from Elections ETC

No real change in our forecast this week.
Despite the flurry of attention around a few polls that give the Conservatives a slight lead (such as this month’s Ipsos MORI and last night’s YouGov), our polling average still has Labour ahead by 1 point (33% to 32%) for a simple reason: there have still been more polls with a Labour lead over the past week and many more over the last two weeks.
The lack of change in the polling average means there’s very little movement in our forecast too. We still make the Conservatives slight favourites to win the most seats next May (with a 54% chance to Labour’s 46%), and make a Hung Parliament slightly more likely than a single-party majority, with a 56% chance.
Our central forecast remains for the Tories to win 300 seats to Labour’s 292 and the Lib Dems’ 28. That’d leave David Cameron’s party 26 seats short of a majority.

Date of forecast: 14 November 2014
Days till the election: 174
Inputted current average poll shares
Con: 32%
Lab: 33%
LD: 8%
Others (inc. UKIP): 27%
– UKIP: 15%
Forecast Election Day Shares (with 95% Prediction Intervals)
Con: 34.5% (±6.8, i.e. 28% – 41%)
Lab: 30.8% (±5.1, i.e. 26% – 36%)
LD: 11.0% (±7.0, i.e. 4% – 18%)
Implied point estimate shares for:
– Others (inc. UKIP): 23.7%
– UKIP: 13.2%
Forecast Election Day Seats (with approximate 95% Prediction Intervals)
Con: 300 (226 – 382)
Lab: 292 (213 – 361)
LD: 28 (23 – 34)
(Prediction intervals assume LD & others shares at central forecast, Con & Lab shares vary as per prediction intervals)
Central forecast: Con largest party, but short of a majority by 26
Approximate probabilities of key outcomes
Con largest: 54%
… with a majority: 25%
Lab largest: 46%
… with a majority: 19%
Hung Parliament: 56%
… with Con largest: 29%
… with Lab largest: 27%
(probabilities may not sum due to rounding)