Quota sampling, herding, socio-economic profiling and weighting – just some of the essential parts that make up the mysterious world of opinion polling. An old political dictum states that one should always ignore the polls, especially if you’re the one running for office. However, in reality they are plastered all over the media, online and print, so who can help but take note.

Amid the hustle and bustle of Manchester’s metro mayor race (well covered by Iceni here and here) other, more exciting, elections are being left at the wayside. West Midlands is the election everyone should be talking about. Not only are the opportunities across the region as enticing as the Northern Powerhouse but the race to become Mayor is on a knife edge.

With 6 unitary authorities, new Metro Mayors, County Councils as well as Welsh and Scottish elections all in May there has never been a better time to demystify the question on everyone’s pre-election lips – What is Purdah?