I’m guessing whatever scale they’re using bottoms out at -2.5 grade levels, meaning a -2.9, a -3, a -6 all get counted as -2.5 creating that bump on the low end
Yeah, that is what’s happening on the chart, but it kind of means their arbitrarily chosen range from -2.5 to 2.5 was not the choice that the data would suggest.
I’m guessing whatever scale they’re using bottoms out at -2.5 grade levels, meaning a -2.9, a -3, a -6 all get counted as -2.5 creating that bump on the low end
yeah I want to know what’s going on with them
Yeah, that is what’s happening on the chart, but it kind of means their arbitrarily chosen range from -2.5 to 2.5 was not the choice that the data would suggest.