Notes Toward an Improbable Result: Grade Points per Pound

Inside Higher Ed has an article on grade inflation this morning, which reminds me of my improbable research theory.

Academic scolds are always talking about grade inflation, saying that the average grade years ago used to be lower than it is now. Medical scolds are always talking about the obesity epidemic, saying that average weights used to be lower than they are now.

Has anyone ever considered that the two might be related? That is, might it be that the grade points per pound has remained constant over the years?

Using some government reports on weight, and totally bias free GPA trends from gradeinflation.com, it looks like the average weight has increased by 15-17% from 1960 to the present. Meanwhile, the average GPA for public schools has increased from roughly 2.5 to roughly 3.0, an increase of 20%.

These are tantalizingly close, suggesting that perhaps the two are linked. The GPA per pound has remained constant to within 5%, well within the uncertainty in these figures, which were estimated by eye from online graphs. And that is surely enough evidence to demand a very expensive investigation into a link between high grades and obesity.

Might it be that the average weight of American students is increasing because their brains are getting huge? It might. (See also the “Flynn Effect”) It would explain a lot.

If anybody wants to sling a large amount of grant money my way, I’ll be happy to give this question the thorough investigation it demands.