Northern Ireland Polling Error Analysis

Click the button below to run 1000 simulations of the Northern Ireland Assembly election using randomised vote shares centred around the current polling average. It applies a layers of variation by tweaking every party's swing in every constituency based on local factors, including average income, urban/rural and whether it is east or west of the Bann.

We use the Monte Carlo method to demonstrate the degree of uncertainty that's inevitable in election projections and show how even small polling errors, and local factors can lead to significantly different outcomes. In many cases the difference between an excellent year for a party and a terrible year is well within a normal polling error.

Click the button below to run the analysis. Results are calculated using the latest polling data.

This simulation uses a normal distribution of errors from the polling average which means that parties are just as likely to overperform as they are to underperform their average. The vast majority of misses will have each party's vote share within 2.5% of the Nowcast but there will be some rare instances where the misses are much larger. The bigger the miss, the less likely it is to occur.