Since the end of October only one survey from a pollster other than YouGov has recorded a CON lead
All the others have had LAB leads or were tied
There’s a new poll reported in the Times today from YouGov which has a Conservative lead albeit a reduced one of 2%.
It has not yet been added to the Wikipedia table featured above of every published poll. When looking in detail at the list one thing is very striking and that is that the Conservatives leads are almost totally from YouGov. All the other polls bar one in early November from Kantar are either showing ties or LAB leads..
Because YouGov publishes more polls than anyone else this might be giving a distorted view of public opinion during what is quite a critical time politically in the UK.
At one stage I used to keep a table showing just the latest poll from each pollster and it might be a case for doing that to get a better and more rounded impression of what is going on.
Nate Silver in the US always talks about the “house effects” of different pollsters and records how particular firms can be out line with the others.
We saw before GE2015 how some pollsters would always record larger UKIP shares than others and there are many examples of what can be termed house effects.