Politicisation of Statistics

I have updated my info page to reflect the fact that I am now a member of Young Nationals. Regard that information as you will.

So it’s fairly appropriate that I post about this topic. Of course, politicians of all stripes have used lies, damned lies and statistics. The whole debacle about what an “average” teacher gets paid is a fairly recent example. (I did find out what Kate Gainsford defines as an “average” teacher. I found an interview on RNZ Morning Report that she rejects the idea of an “average” teacher entirely). There have been more stories in the media about the PPTA strikes, but as usual, they lack the detail and appreciation of the context of the industrial action.

It is more than about pay but that’s what the stories centre around. On that note however, I will admit that my earlier prediction of there at least being three strikes before a circa 2.5 percent increase offer was off. It was only one strike and I don’t think the increase was as big as that.

What was rather disappointing to me was the butchering of the term “statistically significant” which has a specific meaning. But it’s not  surprising. Assisting students in understanding it is something I’ve had to do for hundreds of times as a tutor.

In question four of October 21 question time Bill English provides poor context and explanation of a statistically insignificant finding and David Cunliffe doesn’t let the technical meaning of term get in the way of trying to score political points.

Bill English said:

…The decline in median weekly income is $9, which Statistics New Zealand points out is not statistically significant. It could have dropped for any number of reasons, such as more children in the population, drops in interest rates—

A bit later David Cunliffe asked:

Does the Minister of Finance consider an income drop of $9 a week to be statistically significant to a family who, as Veda Advantage recently reported, are among the tens of thousands of New Zealanders who are finding they just cannot afford to pay their bills?

The word significance in statistics has a different meaning it has in ordinary language of meaningful or important. It relates to how strong the evidence is for making a conclusion based on the data available. In this context, there wasn’t enough evidence to conclude that there was an actual drop in the median income.

Bill English instead could have said something along the lines of Statistics NZ could not find conclusive evidence of a drop in median incomes. The reasons for a drop in his answer have nothing to do with “statistical significance”. A correct explanation in this case would have been far more suitable for him politically. He could have truthfully said “there is no evidence of a drop in median income”!

Despite lies, damned lies and statistics, Statistics NZ is a very trusted department. The Minister of Statistics in the past several years of government of both parties has been asked the fewest oral parliamentary questions. Hardly even patsy ones!

David Cunliffe outright butchers the term, using the words “statistically significant” well outside of its technical meaning, when he really meant the ordinary meaning of the word. He shouldn’t have used the $9 figure, but if he had to he should have asked whether Bill English considered “a median $9 to be unimportant” for the average family. (There’s that politically charged word “average” again…)

Secondary Teachers Contract Bargaining

The NZ Herald recently reported that a strike over pay and conditions is possible course of action. The government clearly has not impressed the PPTA with small offers of 1 and 1.5 percent increases on the bargaining table. I have heard that the government also wishes to claw back benefits like guaranteed non-contact time in a bid to save money. Faced with a strike (which looks likely in the current climate) I think the government will make a more realistic offer. It would seem that the government is quite intent on wearing down the resolve of the union and to drag things out for as long as possible. Why this is so I am unsure.

Nearly all sectors of government spending have been cut due to the recession, and there’s always the mentality “we agree that budget cuts are necessary, but not our sector…” which can easily take hold. Along with the likes of Health, Education is something a government is never allowed to spend less money on. Perhaps National are wary of the fact that PPTA can hold the government to ransom if they have to, with 95% plus of secondary teachers belonging to it. Even though they know they would come out poorly in a head to head confrontation they are dragging things out for as long as possible to attempt to portray themselves, not teachers as setting the agenda on education policy. It is not a good look for a government to have to beg teachers to carry out their policy, particularly election winning ones. Perhaps they are dragging things out for as long as possible so that the government can say “look, we tried to find a solution, but we couldn’t so sacking many teachers (or something else quite extreme) was inevitable” with some credibility. Maybe it’s a distraction that the government is willing to bear to take attention away from the opposition to National Standards in the primary sector.

Pay is always one of the more visible issues when it comes to teacher recruitment and retention. However, as far as pay and career progression goes, once you hit the top of the standard payscale, the only way to get more money is to do less teaching. The current secondary scale has 14 steps and most new teachers with a Bachelor’s degree and a teaching diploma would start on step 7 (current starting salary $45653 pa), and go up one step a year. Once the top is reached ($68980 pa) one can only get paid more by getting management units, as a department/faculty head, deputy principal duties, et cetera which entails more paperwork and less teaching.

One may think that it’s a fairly good salary considering that there are two week school holidays between terms and a fairly long summer break. The reality is though – teaching is a stressful job. It’s the most difficult thing I’ve tried to do in my entire life. Teachers get stressed, and also get ill quite easily from hanging around so many young people every day with all sorts of ailments. The hours are more than just during the 9am-3pm ish teaching day – many hours of preparation, marking, taking the rugby or debating team are a few of the many commitments teachers are expected to make. The skills teachers have often are better renumerated elsewhere, especially say those have skills in Mathematics.

Thursdays in Black

So the PPTA rejected the latest pay offer when negotiating a new collective agreement. I would have too, the rises of 1 percent and 1.5 percent are not very much! So what do the PPTA members do? Do something I associate more with useless tertiary student politics groups (useless because they have no real power or influence at all thus a waste of time) than a group of professionals and decide to wear black on Thursday.