Via Peter Suber, I am delighted to find that Stuart Shieber has started a weblog, and even more delighted that in one of his first entries he has turned my long-ago author-side fees DOAJ hack into an actual, readily reproducible study:

Here are the results computed by my software, as of May 26, 2009:

Charges.......................951  (23.14%)
No charges....................2889 (70.29%)
Information missing...........270  (6.57%)
Hybrid........................1519 (26.99%)
Total.........................5629

The numbers are consistent with those of Hooker's study some 16 months earlier.

It's great to have the numbers confirmed, and even better to be able to make regular updates and construct time series. Thanks to Stuart for doing it right, and for making the code freely available.

(Note, had to reformat the quoted table into ugly text, because I still can't get MT to play nice. Grrr.)