The Dim-Post

May 29, 2012

A teacher rants about class sizes

Filed under: education — danylmc @ 3:44 pm

A teachers’ lament. Forwarded to me for anonymous publication:

Treasury have said that they want to raise class sizes so that they can pay for fewer teachers, so they can allocate that money to other things for education.

For a start, whenever anyone suggests monkeying about with education, the litmus test I use is: what would happen if you did it to doctors? For example: If a hospital had the best and most state-of-the-art equipment but almost no doctors to use it, most people would call that a bad idea. Most people would ask, I imagine, why the hospital couldn’t have the fancy equipment AND a large staff of highly-trained doctors. Actually, a lot of people have been asking that question for a very long time now. Especially those on waiting lists. Of course, the moment it stops being about something important (your health) and starts being about something that doesn’t matter in the slightest (your children) then all of a sudden the stakes don’t seem so high.

The government (you remember those guys) has said that it will not under any circumstances discuss class-size – even on the rare occasion it is willing to offer us more money and non-contact time. They often throw John Hattie’s research on the table; specifically the bit that says class size makes no difference to achievement. What doesn’t get thrown around so freely is how those sorts of statistics get compiled. Here’s a scenario for you…

My school has 75 kids starting this year. (We have many more, but I’m being hypothetical here…) We are going to divide them into three classes, called The Smart Class, The Average Class, and The Dumb Class. (There’s a longer discussion about the fun euphemisms schools use to describe these things – but be honest; whatever they were called, you knew which one you were in when you were in high school, didn’t you? So we’ll be damningly truthful about the titles for now and you can yell at me later.) Each of these three classes should have around 25 students. Except of course, the students in The Dumb Class need more help than their more able counterparts. They need more one-on-one time and more personalised assistance In addition to this being basic common sense, it’s also been proved in studies quoted by the Ministry of Education (which they follow with studies that say increasing class size won’t matter, which is sort of cognitive dissonance, but who am I to judge?). In order to make sure that the lower ability students are properly catered for – and have a chance to achieve at the same level as their peers – we take certain steps, such as giving a teacher-aide to that class. The main step we take is to ensure that the class only has fifteen students in it.

To accomplish this, of course, we have to move the ten most able of the bottom-end up to The Average Class. Which now has 35 students. So we have to move the five most able of them into the Smart Class.

I start the year with The Smart Class and The Dumb Class – The Average Class is taught by some other poor doomed soul, so they leave our narrative for now. I spend all of Monday explaining the work, and they have Tuesday’s period to complete the task.

Here’s how that goes in The Dumb class: Fifteen students in an average period of one hour have myself and the teacher-aide to sit with them, explain the task, help them with it etc. The maths works out as each student having eight minutes of one-on-one time with an adult to assist them with their work. (60÷15×2) Also, if one of the students is disruptive, I can move them away from their peers (probably right up near me – you remember how that works). If they continue to be really disruptive, I can take them out into the corridor for a while, while the teacher-aide watches the rest of the class, and I do my student-whisperer act to calm them down.

Next period, The Smart Class of 30 comes in and I try that again. The absence of a teacher-aide means that this class has only two minutes each of one-on-one time with an educator to help them. (60÷30×1) Of course one hopes that members of The Smart Class need less one-on-one time to understand the work. But 75% less? Sure, they might not need eight minutes, but what if they need three? This is particularly pressing because, you’ll remember, five (at least) of these students aren’t actually high-ability – they are (cue menacing music) Average, but have been shunted uphill to even-out the class numbers. They’ll start drowning if I go too fast, but the rest of class will lose interest if I slow it down too much. If one of the students is disruptive (and yes, The Smart Class has less of this than The Dumb Class, but when you cram 30 teenagers into a stuffy room in the February heat, oddly enough they’re not all on their best behaviour) I can’t easily move them – there are 30 desks in my class and no one is away that day. In order to move the naughty student, I have to look into the eager eyes of the Good Student who volunteered to sit next to my desk and say “Oi you, the hard working one who’s always eager to please and wants to do well academically. Go sit up the back with a pack of hooligans who hate you, because I want their ringleader to sit in your seat. Off you toddle.” Also, if one of them is really disruptive, I have to think long and hard before taking them out of class, because that would mean leaving 29 others (who are all het-up and excited that one of their number is getting in trouble) on the other side of a door without direct supervision for five minutes, which is enough time for some of my students to get into extinction-level trouble.

So, because The Dumb Class are all working at roughly the same level and the school has gone to great efforts to create a positive and constructive learning environment, they all get a grade of Achieved – basically a C in oldspeak. This is a minor miracle, as most of them have never gotten such a high mark in their lives, and proves that I’m a great teacher. Let’s have a look at The Smart Class’ results…

Because at any given point over fifteen percent of the class was struggling to keep up with the work, and the learning environment was one where not only did I have difficulty catching them up, but where I had almost no one-on-one time with the students and where behaviour problems escalated rather than diminished, most of these students do remarkably badly. These top-end, Merit/Excellence students only get grades of Achieved. This means that I – and the school – have failed them. Instead of pushing them to bigger and better things, they have ended Year 9 roughly as clever and with approximately the same amount of knowledge as they began it.

So, after all this has been done, Ministry Faktdrones™ come in and look at one piece of paper that has all of our grades on it. They don’t look at the students as humans, don’t look at any of our processes, and often don’t even look at previous results which would let them know things like value-added results. They look at one sheet of results and say “Look here – the class with 30 all got Achieved, and the class with 15 all got Achieved too. That means, statistically, class size doesn’t make a difference. Let’s cram forty of the little firestarters in there next year!”

Something I constantly and tiresomely have to harp on about when I’m talking to (at?) people about this and other education issues, is that the students are not statistics, and sometimes can’t be pigeonholed to fit a statistically clean model. That means in order to explain the truth behind the “clean” stats presented by the Ministry, I have to ramble on for pages just to get a simplified version out (and let me tell you – the above was a lot of smooth lines compared to the dirty reality of timetabling) but the Ministry can point to one page of clean, fresh statistics and say “Look, it says here they all got the same marks – pay no attention to the raving hippy.” That means – simply in terms of PR and getting the message out – that their job is easier, and their message is more palatable and easy for the public to understand. Doesn’t make it true, though. And it sure as hell doesn’t help the students, which is what they tell me is the point of this whole exercise in the first place…


Filed under: Politics — danylmc @ 2:01 pm

In much the same way that astronomers look for extra-solar planets through indirect measurements, like variations in the velocity or light intensity of the sun it’s orbiting; we occasionally get indirect indications on how the governments’ policies are going down in the electorate as measured by their overnight tracking polls by their desperate backpedaling and frantic blaming of officials every time they botch the introduction of some new policy.

‘Fixing’ the education system by increasing class sizes was the brain-child of Treasury – the public service wing of the ACT Party – so it wasn’t hard to predict that it would meet with overwhelming public revulsion, or that if implemented it will be an expensive failure.

May 26, 2012

More poll chart porn

Filed under: polls — danylmc @ 9:38 am

Peter Green put together an R script that generates an svg file showing historical polling trends. It estimates polling bias and factors it into the trend-line. Unfortunately WordPress won’t let me post svg files, so here’s a screen-capture of the result below. If you download the actual file and open it in a browser that isn’t Internet Explorer you can click on individual polls and highlight trends from different pollsters. The yellow lines below the x axis are significant political events. If this was an svg file you could click on them and find out what they were. Peter’s explanation of the statistics below the jump:


May 24, 2012

Low hanging rotten fruit

Filed under: economics,Politics — danylmc @ 9:27 am

Today the Dom-Post has the results of an (unscientific) poll showing that National’s return to surplus has overwhelming public support. It’s an indication of how utterly our public debate and understanding of these issues is dominated by National’s rhetoric. Getting out of debt is important to do if you’re an individual and you’re going to retire and have no income at a fixed point in time, and it’s nice if you’re a corporation, because surplus helps you maximize shareholder returns – but if you’re a nation-state with a robust economy then being in debt really doesn’t matter very much.

Put it this way: it would be nice to have a surplus – but it’s not more important than:

  • reducing our massive private debt
  • reducing our superannuation liability
  • reducing unemployment
  • reducing the loss of skilled workers to Australia
  • increasing our anemic wage growth
  • improving business productivity
  • improving our capital markets
  • improving our savings rate
  • adding value to our exports

And that’s without getting into ‘ideological territory’ like reducing inequality or addressing carbon emissions. So while getting back into surplus is a nice thing to do, it’s probably not even the tenth most urgent problem the government needs to address.

But rushing back to surplus involves doing a bunch of stuff English wants to do anyway – privitise assets, slash the public sector, make the governments revenue base more regressive – which is why it’s his top priority and all of the serious, real issues facing the New Zealand economy are being completely ignored.

May 23, 2012

A question from a non-economist

Filed under: economics — danylmc @ 6:37 am

So tomorrow’s budget is going to be another ‘zero budget’, because it’s incredibly important for the government’s accounts to return to surplus before the next election  to maintain fiscal credibility. And Labour agrees that getting back into surplus real fast is real important.The contention between the two main parties is which one of them is responsible for all the current debt.

But looking at the principle features of our economy, we currently have:

  • A lot of unemployed people and record levels of workers migrating to Australia.
  • Close to zero economic growth
  • A huge amount of infrastructure that needs building or upgrading (including an entire city)
  • The government can currently auction its bonds at historically low rates

Doesn’t that combination of factors make this a really good time to borrow a lot of money and invest it, instead of hurrying to pay down debt? Are there sound reasons why we aren’t at least talking about that as an option?

I know the right-wing talking points: that householders and the private sector never run their finances that way, which is why nobody in New Zealand has a mortgage and the corporate bond market doesn’t actually exist; that borrowing and investing is ‘what happened in Greece’. (That is not what happened in Greece.) And, viz Matthew Hooton on RNZ last week, that it is literally impossible for the government to create jobs – so if it borrowed $350 million dollars to build a convention center in Auckland, say, the universe itself would intervene to prevent an increase of jobs in the construction or tourism sectors.

But are there actual, serious reasons the government doesn’t take advantage of current conditions? Would a policy of borrowing and investing to grow productivity really make creditors and the bond market cry?

May 22, 2012

How efficient!

Filed under: general idiocy — danylmc @ 1:52 pm

Via TV3:

The Government has launched a new smartphone and tablet application based around the release of the Budget on Thursday.

The new app will allow users to look at documents from the Budget, read press releases and watch video coverage of the Budget’s release.

The app was designed and built in four weeks by developer PaperKite and will be available for download tomorrow afternoon.

Finance Minister Bill English says the app, called NZ Budget, was funded through savings made in the printing process.

 He says the app is an example of the Government keeping up with the times.

Now when I’m in-between meetings – or simply waiting for the bus – and I want to know the 2016 forecasts for the governments depreciation and amortisation costs I can simply use this new NZ Budget app on my smart-phone instead of the web browser on my smartphone.

May 19, 2012

Tracking poll page

Filed under: polls — danylmc @ 7:00 am

I’ve created a permanent page for the tracking poll graphic. I’ll try to update it as new poll results come out.

I always knew in an intellectual sense that individual poll results were largely meaningless and that the long term trends were what counts, but – to me – this chart really hammers that home. The data is as noisy as hell. Take a look at some of the results just prior to the 2008 election: they showed a really close race, which wasn’t actually close at all.

So every time there’s a new poll out and the political editor publishing it breathlessly speculates on the reasons behind the ‘dramatic gains’ or whatever, it might help to remember this chart and the semi-random distribution of most of these individual results.

May 17, 2012

They write letters

Filed under: general idiocy — danylmc @ 11:31 am

May 16, 2012

I’ll be there for you . . .

Filed under: general idiocy — danylmc @ 9:51 am

Via the Herald:

Justice Minister Judith Collins told Fairfax Media authorities could apply to the High Court to have sex offenders housed in a “flatting situation” within prison grounds, with offenders able to ask for a review.

You’re all too late. I’ve already applied to NZ On Air for a $450,000 reality show documentary, ‘New Zealand’s Got Rapists!’

May 14, 2012

Big Picture

Filed under: polls — danylmc @ 8:58 am

Thanks to Bradluen who came through with the R code I begged for in my previous post. It’s available here. He comments:

Currently the lines don’t go through the actual election results. However, just upweighting the election results in the Loess gives weird results. In fact I kind of think Loess isn’t quite right here. Use another smoother?

Here’s the resulting chart from the Wiki polling data showing aggregated poll results since the 2005 General Election:

The black lines are election dates. Why is Labour trending down, even though most of their post-election polls have been improvements on their election result? My guess is all those low poll results just before the election are weighing the distribution. Should the polls be weighted by date? Update: changed the parameters of the script to generate a slightly different graph.

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