Catherine Shreves weighs in:
>Minneapolis also has its own research department which has been
>documenting the gains in achievement of those stduents who have been
>with the MPS for their entire school career, and therefore benefiting
>from the lower class size. For example, 79.4% of students who had 7
>years of lower class size have passed the Minnesota Basic Standards Test
>(Reading) compared with 53.5% of students who have had 1-3 years of
>lower class size, and 42.3% of students who had no years of lower class
>size.
I get so little work out of my statistics degree, I have to use it when I
can....
In the above comparison, were the groups' other variables controlled? In
other words, are we talking about roughly the same demographic population in
each group? It's possible kids with seven years in smaller classes were,
say, wealthier (or at least better-connected), or from more stable homes, or
superior in other demographic attributes that have predicted achievement...
While I trust Catherine completely (this is not sarcasm), I'm always
suspicious of an overall stat without seeing how it was derived. Guess they
taught me too well to show my work in public-school math-class. It's not
Catherine's responsibility to do this, I'm just curious for more
information.
David Brauer
King Field - Ward 10
