Test Case 2: Four practical Natural Language grammars from (Tomita 1986, pages 171 to 184 Appendix F)

The grammars used were: G1 (8 rules), G2 (40 rules), G3
(220 rules), and G4 (400 rules). We used two sets of input:
a) the two most-ambiguous inputs from Tomita's sentence set 1
(page 185 App. G) of lengths 19 and 26 which
we parsed with G3 (as did Tomita), and
b) three inputs of lengths 4, 10, and 40, with systematically
increasing ambiguity, from Tomita's sentence set 2.


Input  No. of     Our method            Tomitas
length Parses     G1    G2    G3    G4| G1    G2    G3    G4
-------------------------------------------------------------
Input from Tomitas sentence set 1
-------------------------------------------------------------
19      346                  0.02                   4.79
26    1,464                  0.03                   8.66
-------------------------------------------------------------
Input from Tomitas sentence set 2
-------------------------------------------------------------
22      429   | 0.02  0.02  0.03  0.03|2.80   6.40  4.74  19.93
31   16,796   | 0.02  0.02  0.05  0.08|6.14  14.40 10.40  45.28
40  742,900   | 0.02  0.06  0.08  0.09|11.70 28.15 18.97  90.85