January 1, 2014

I can haz public opinion?

Usually it’s a problem for opinion polls that respondents tend to answer based on political or group affiliation rather than their actual opinion about the real issue.  Today’s Herald has a poll where that’s basically the point. This is a real poll, not one of those bogus clicky things, but the question was “Who would you trust most to feed you cat over the holidays?”


Now, to start with, just over half of NZ households do not haz cat, so the question is pretty meaningless for them. Even for the 48% with feline overlords,  the answers supplied didn’t include anyone you might actually get to feed your cat over the holidays. (And isn’t the kitten in the photo a bit young to be left alone like that?)

The choices were one MP (out of 121), one big-city mayor (out of, say, four to six), one internet celebrity (out of an indeterminate set), and one former MP and climate-change denier. No women. No-one on the paper’s New Zealanders of the Year list. Unsurprisingly, one in three of the people they managed to get to answer the question looked at the options and said something along the lines of “Do not want”. 

It’s unusual for a statistician to say this, but sometimes getting a properly representative sample doesn’t really help all that much. The one person on the list who is actually known for his commitment to animal welfare came last.

(picture via @ChrisKeall)


Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »


  • avatar

    The key word in the question is undoubtedly “trust”. It probably wouldn’t matter if it was who to “trust to feed your pet”, “trust with the nuclear launch codes” or “trust to put a 10c piece in a charity box”, the outcome could well be similar. Put an emotive word in the question, everything else goes out the window.

    4 years ago

    • avatar
      Thomas Lumley

      That’s my point, I think. In real life you trust different people with different things — there are people I’d trust with feeding my hypothetical cat but not with keeping a secret, and vice versa.

      The poll just measures some sort of positive or negative emotion, partly because we don’t really know much about those people, and partly because that’s what polls are like. Usually it’s a bug, but in this case the Herald are trying to turn it into a feature.

      4 years ago

  • avatar
    Nick Iversen

    There is a poll in the Herald today (2 Jan) and my first reaction to it was – “Enough with the polls, Herald!” They don’t tell you anything useful and I’m a bit sick of them. The Herald’s new year resolution should be to do away with insignificant polls this year.

    Anyway, I was going to skip the page but the headline (again a misleading one) “trial speed limit” was enough of a hook. Turns out that it wasn’t about a change in speed limits. Just tolerances.

    The poll was bogus too. The two answers allowed were “fair cos it’s about safety” and “unfair cos it’s about revenue raising”

    Other options such as thinking they were fair or unfair but for different reasons weren’t allowed.

    4 years ago