## Professor Dorn Dodges the Point

"Forest?" We trees haven't seen one of those...

Sherman Dorn takes issue with Andrew Coulson’s spending/NAEP chart and my use of it. Just a reminder, here it is again:

Professor Dorn infers that Andrew took a present inflation adjusted spending per pupil figure and multiplied it by 13 to arrive the inflation adjusted cost per pupil instead of adding 13 seperate spending per figure numbers.

Because we spent less in the past than we do in the present, such a proceedure would be more appropriate for a projection of the future (with an inflator) rather than a documentation of the past. Dorn correctly notes that the per pupil numbers double rather than triple as implied by the chart pointing to the NCES source data. Unless Andrew is calculating some sort of net present value type of cost, Dorn seems to be on solid ground so far.

After that, Dorn’s post gets silly by taking the log function of spending data, etc. in a successful attempt to create a far more troublesome chart based on the same data.  Dorn however is missing the forest for the trees, even if he is right.

First note the absurdity of the phrase “only doubles” in practical terms. Let it breathe a bit, twirl it around in your glass, sample the aroma of it. When you partake of it, let it set in your palate for a bit before moving on.

What does a doubling of effort look like? Well, fortunately, all the charts in the post that Dorn ignored answer that question. Here they are again:

Yep, that looks closer to a doubling than a tripling all right, unless of course the real total cost of the average teacher has gone up rather than down over the decades. Teachers of course are a small issue compared to this:

Oh, but not to worry- all these extra employees per student have vastly improved the quality of learning for our students. Err, except…

Hey no fair! The reading scores for 17 year olds may have only gone up one point despite a doubling of spending, but the math score gains have been better!

Umm…like a two point instead of a one point gain!

Bottom line: we’ve bombed our students with extra school employees and have very little to show for it in terms of academic outputs.

Now you won’t be getting any “fake but accurate” arguments from me. Unless I get a solid explanation from Andrew, which I still might, I won’t make any further use of the chart. These other charts make the point just fine.

### 6 Responses to Professor Dorn Dodges the Point

1. Patrick says:

Using the NCES inflation adjusted data the total per pupil increase between 1970 and 2007 was 125 percent

Drop back to the 1949-50 school year and the total per pupil spending inrease through 2007 rises to 465 percent. Double the teachers per student and 5x the money.

The main point still stands – the cost of public education is rising far faster than productivity gains which appear flat, at least since 1970.

2. I’ve put my response in an addendum on the original post. The substantive question is fair — whether or what part of rising per-pupil spending has been a good social investment — but that is separate from my point about presentation of data.

Also, regarding the picture: I have more hair on my chin than hobbits, but less on my feet.

Duly noted…I’ll see if I can find a picture of Treebeard with Gimli…:-)