“Eppur si muove,” Galileo is reputed to have grumbled sotto voce as he formally recanted his claim that the earth orbited the sun instead of the other way around. He was on trial for heresy: these days, in Harper’s Canada™, you merely get shushed by your bosses. And sometimes your own integrity forces you to abandon your post.
The government’s war on data continues, with all of its quasi-religious fury. Senior managers at Statistics Canada are telling rebellious mathematicians to keep their opinions to themselves about the voluntary household survey that has replaced the long-form census.
The atmosphere at the at present has proven too much for Statistics Canada’s chief economic analyst, Philip Cross, who, like his former boss Munir Sheikh, has finally decided to pack it in:
Mr. Cross is concerned that the free exchange of ideas at the agency is diminishing, and that internal dissent is no longer being tolerated by senior managers – particularly when it comes to discussions about the 2011 census and new national household survey.
…Survey response rates are his chief concern – the 69.3-per-cent response rate from the household survey is based on distribution to a third of households, meaning it’s actually based on answers from a fifth of the population. And it’s still unclear, he said, which segments of the population are missing from the sample.
“The focus on response rates ignores questions about the quality and distribution of the responses, but discussion of the latter issues is limited by management’s insistence on being ‘on-message’ all the time about [2011] census and NHS being a success.”
You don’t need a PhD in stats to know that a voluntary survey will always yield skewed data—check out those bizarre on-line media “polls” if you doubt this. The element of self-selection introduces sampling bias that vitiates the value of the data collected. But the word has come down from the Harper government: until further notice, the sun revolves around the earth. And if you don’t like it, shut up or leave.
[H/t drmarcspooner]