Two useful posts by Whale on a couple of polls.
First he comments on the Horizon poll that the Maori Party is encouraging their activists to sign up for the poll. It is quite possible they are not the only minor party to be doing so. This is one of the weaknesses in allowing people to sign up for a poll.
It can make a lot of sense for a minor party to do this. If the poll is of 1,000 people, then just 10 activists can get you an extra 1% if they are all selected for the poll. This is why it is desirable to have a huge sample size for your online panel (YouGov in the UK have hundreds of thousands), so you can minimise impacts like this.
Whale also comments on the poll done that alleges Colin Craig is leading in Rodney. I had been critical of this reported poll also as the report published by the Conservatives does not include the actual question asked. Anyway, Whale reveals that the director of the firm which did the polling is a candidate for the Conservatives. This should have been revealed at the time, in my opinion.
This does not mean that the poll results are or are not valid. As I said, validity is based on knowing the question asked and the methodology. You can poll for an organisation you are involved with. For example, Curia does an annual poll for the Republican Movement on whether people want NZ to become a republic when the Queen dies. Now I am on the Council of the Movement, but this doesn’t influence the results. The key thing is I have publicly disclosed my involvement. Incidentally we found this year a quite large drop in support for becoming a republic – I suspect a consequence of the royal wedding. So poll results are not always pleasing to the client.