Some preliminary results
n A study of 60 classes around the country by
Dick Hake* shows that across a wide range of
initial states the fraction of the possible gain is
similar for classes of a similar structure.
n For traditional classes he finds
     h » 0.20 ± 0.05
* R. R. Hake, Am. J. Phys. 66:1, 64-74 (1998)
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