December 20, 2013

Best? Worst? It’s all just numbers

From the Herald, based on a survey by a human resource company that’s lost its shift key

“New Zealand lags behind other Asia-Pacific countries in wage equality”

From the Ministry of Women’s Affairs, based on the Quarterly Employment Survey

New Zealand’s gender pay gap is the equal lowest in the OECD (along with Ireland). The gender pay gap at 10.1 percent (2013) is the lowest in the Asia-Pacific region.

It’s not that Herald personnel don’t know about the Government figures: about a month ago they ran a story describing the small but worrying increase in the governments estimate of the pay gap.

Now, it could be that both these things are true — perhaps they define the pay gap in different ways, or maybe the gap is much larger in some industries (and, necessarily, smaller in others).  But if you’re going to run a dramatically different estimate of such an important national statistic, it would be helpful to explain why it is different and how it was estimated, and say something about the implications of the difference.

Especially as once you find the company on the web (quite hard, since their name is “font”), you will also find they run an online salary survey website that provides self-reported salaries for a self-selected sample.  I hope that isn’t where the gender pay gap information is coming from.



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 »