More Teachers ≠ More Graduates

It is Spring and VDOE has posted the teacher data it has had since September.  So let’s look at the relationship between those numbers and the graduation rates.

First, the “Federal” graduation rate, i.e., the sum of standard + advanced diplomas in the 4-year cohort divided by the cohort size.


The fitted line might suggest that hiring more teachers leads to lower graduation rates but the tiny R-squared value tells us the two variables are quite uncorrelated.

Richmond is the gold square there.  The red diamonds are the peer cities, from the left Newport News, Hampton, and Norfolk.  Charles City is green; Lynchburg, blue.

As we have seen, VDOE has inflated the federal graduation rate by using “credit accommodations” that permit counting Modified Standard Diplomas as “Standard.”  They do an even better job of cooking the data by defining an “On Time” rate; in 2017 that deception raised Richmond’s federal rate of 70.1% to a bogus 76.8%.

Here is the happier picture painted by this manipulation:


Again the two variables are not correlated.  The inflated numbers make Richmond (and the Board of “Education”) look a bit better but do no good at all for the Richmond students whom the system has failed to educate.

Interesting note: For Charles City, both rates are 92.6%.