Procedure for quantitatively comparing the syntactic coverage of English grammars

The problem of quantitatively comparing the performance of different broad-coverage grammars of English has to date resisted solution. Prima facie, known English grammars appear to disagree strongly with each other as to the elements of even the simplest sentences. For instance, the grammars of Steve Abney (Bellcore), Ezra Black (IBM), Dan Flickinger (Hewlett Packard), Claudia Gdaniec (Logos), Ralph Grishman and Tomek Strzalkowski (NYU), Phil Harrison (Boeing), Don Hindle (AT&T), Bob Ingria (BBN), and Mitch Marcus (U. of Pennsylvania) recognize in common only the following constituents, when each grammarian provides the single parse which he/she would ideally want his/her grammar to specify for three sample Brown Corpus sentences:The famed Yankee Clipper, now retired, has been assisting (as (a batting coach)).One of those capital-gains ventures, in fact, has saddled him (with Gore Court).He said this constituted a (very serious) misuse (of the (Criminal court) processes).