Both show the lack of correlation between a teachers’ score on the exceedingly complex Teaching and Learning Framework classroom observation scores on the one hand, and their scores on the Individual Added-Value measurement scheme either in math or reading or both, depending on what subject(s) and grade levels that they taught.
Gary’s graph is, of course, populated by lots of bright red triangles; mine has little blue squares. His grid is missing vertical lines, so mine is clearly better. (joke !) But look even more carefully – you can see that the individual triangles and squares are in the identical places.
This shows that Excel, when given the same data, will produce much the same graph.
It’s really easy to do, by the way. You should try it. Here is the original data table.