UK 2015 – Forecast – 16th March


This is the latest of our forecasts for the UK General Election in 2015. To see our methodology click here. To read a note on our updated forward looking projection methodology, click here.

Forecast

  • Our forecast sees a levelling in the Conservative midpoint position, but a clear reduction in their probability of forming a majority government.
  • The SNP position continues to strengthen in Scotland (our probability of Labour being beaten in the seat count in Scotland is now 100%) and this dampens any expectation of a Labour plurality despite the Labour vote holding up.
  • The support for UKIP continues to fall (and as we have shown here, is the only statistically significant trend since the start of 2015).
  • A Wales Barometer poll has given us a more robust view of the position in the Principality.

Our mid point and confidence interval forecast for seats is as follows.

Party Seats – Most Likely Outcome Seats 50% CI Seats 95% CI
Conservatives 306 301 – 311 295 – 321
Labour 269 261 – 275 244 – 288
Liberal Democrats 7 5 – 8 3 – 12
UKIP 1 0 – 1 0 – 12
SNP 44 41 – 48 34 – 52
PC 3 3 – 4 1 – 4
Others inc. Green (GB) 2 2 – 4 0 – 6
Irish 18 n/a n/a

Our mid point and confidence interval forecast for votes (mainland GB) and our centre point for seats is as follows.

Party Vote% – Mid Point Vote% 50% CI Vote% 95% CI
Conservatives 34.0 33.4 – 34.6 32.4 – 35.8
Labour 32.7 31.7 – 33.8 29.7 – 35.8
Liberal Democrats 10.3 9.9 – 10.8 9.0 – 11.8
UKIP 13.0 11.8 – 14.3 9.1 – 17.0
Green 4.7 3.5 – 5.9 1.3 – 8.2

Our probability of different outcomes is as follows.

Event Probability
Conservative Majority 0.5%
Conservative Minority 98.6%
Exact Tie Labour and Conservative 0.2%
Labour Minority 0.7%
Labour Majority 0.0%
UKIP more votes than Liberal Democrats 88.8%
Greens more votes than Liberal Democrats 0.1%
Greens more votes than UKIP 0.0%
Green > LD > UKIP (votes) 0.0%
LD > Green > UKIP (votes) 0.0%
LD > UKIP > Green (votes) 11.2%
UKIP > Green > LD (votes) 0.1%
UKIP > LD > Green (votes) 88.7%
UKIP get more votes than Labour 0%
SNP largest party in Scotland (seats) 99.9%

What are the main points of your forecast?

We identify the following events / features.

  • We continue to see a decline in the support for UKIP
  • Although the Conservatives lose seats to Labour, Labour lose a significant number in Scotland to the SNP, all but destroying their chance of a workable plurality. We are now treating the SNP surge in Scotland as consistent and lasting.
  • The Liberal Democrats will struggle to poll significantly above 12%. This will have a dramatic effect on their attempts to retain seats. Furthermore, recent constituency level polling indicates that the expected Liberal Democrat incumbency effect is not as strong as has been thought. This aspect of our forecast differs from other similar forecasts and we will continue to not add any significant incumbency effect for the Liberal Democrats until we see constituency level polling evidence to the contrary.

The key aspect of our forecast is uncertainty. We now show a variance of possibilities from a Labour majority to a Conservative majority. We still believe the most likely outcome is a Conservative minority government.

What improvements are you hoping to implement next?

At the moment the model isn’t taking into account polling in individual seats. As such data becomes richer and more available we will attempt to use it.

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