he total number of doors open in the ten settings is
thirty-five, and since in each of the ten settings one door is
describable as the right door, the probable ratio, apart from the
effects of training, of right to wrong first choices is 1 to 2.50. It is
evident, therefore, that Skirrl in his first series of trials closely
approximated expectation in the number of mistakes.

TABLE 1

Results for Skirrl, _P. irus_, in Problem 1

========+==========+=========+=========+===========+=============+===========+===========+===========+=============+===========+===========+===+===+========
| No. | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | | | Ratio
Date | of | | | | | | | | | | | R | W | of
| trials | 1.2.3 | 8.9 | 3.4.5.6.7 | 7.8.9 | 2.3.4.5.6 | 6.7.8 | 5.6.7 | 4.5.6.7.8 | 7.8.9 | 1.2.3 | | | R to W
--------+----------+---------+---------+-----------+-------------+-----------+-----------+-----------+-------------+-----------+-----------+---+---+--------
April | | | | | | | | | | | | | |
19 | 1- 10 | 1 | 9.8 | 6.7.3 | 9.7 | 6.2 | 7.8.6 | {6.7.7.7 | 4 | 7 | 2.3.3.1 | 3 | 7 | 1:2.33
| | | | | | | | {6.5 | | | | | |
| | | | | | | | | | | | | |
20 | 11- 20 | 3.2.1 | 9.8 | 5.3 | 7 | 4.2 | 8.8.6 | 5 | 8.4 | 7 | 3.1 | 3 | 7 | 1:2.33
21 | 21- 30 | 3.1 | 8 | 3 | 8.7 | 6.2 | 6 | 5 | 6.4 | 9.7 | 1 | 5 | 5 | 1:1.00
22 | 31- 40 | 1 | 9.8 | 3 | 7 | 6.2 | 6 | 6.7.5 | 5.8.4 | 9.8.9.8.7 | 2.1 | 4 | 6 | 1:1.50
23 | 41- 50 | 2.3.1 | 8 | 5.7.3 | 7 | 4.2 | 6 | 5 | 7.8.4 | 7 | 3.1 | 5 | 5 | 1:1.00
24 | 51- 60 | 1 | 8