TABLE 2

Results for Skirrl,P. irus, in Problem 2

========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+======== | No. | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | | | | | Ratio Date | of | | | | | | | | 1.2.3.4.5 | | | R | W | R | W | of | trials | 7.8.9 | 1.2.3.4 | 2.3.4.5.6.7 | 1.2.3.4.5.6 | 4.5.6.7.8 | 1.2.3 | 2.3.4.5 | 6.7.8.9 | 1.2.3.4 | 3.4.5.6.7.8 | | | | | R to W ————+—————-+———————+———————+———————+———————+———————+———————+———————+———————+———————+———————+—-+—-+—-+—-+———— May | | | | | | | | | | | | | | | | 11&13 | 1- 9 | 7.7.9.7.8 | {1.2.2.1.4.1 | {2.3.2.3.2.5 | {4.6.1.4.1.1 | 4.4.7 | 3.1.2 | 4 | 4.1.8 | 1 | | 1 | 8 | 1 | 8 | 1: 8.00 | | | {2.1.2.1.3 | {2.3.2.5.6 | {2.6.1.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | | | 24 | 11- 20 | 8*[1] | 2.4.3* | 4.5.6* | 2.2.5* | 5.6.6.7* | 3.1.2 | {5.2.3.5.3.2 | 4.6.8* | 4.4.3* | 5.5.6.7* | 0 |10 | 0 |10 | 0:10.00 | | | | | | | | {3.5.2.4* | | | | | | | | | | | | | | | | | | | | | | | | 25 | 21- 30 | 8* | 4.4.3* | 5.6 | {6.6.2.3.4 | 6.7 | 2 | 4 | 5.6.3.8 | 4.4.3 | 6.4.6.8.7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | {6.6.5* | | | | | | | | | | | | | | | | | | | | | | | | | | | 26 | 31- 40 | 8 | 4.3 | 6 | 4.5 | 6.7 | 3.2 | 5.4 | 5.8 | 4.3 | 5.3.8.7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | | | | | | | | | | 27 | 41- 50 | 8 | 4.4.3 | 6 | 5 | 6.8.6.8.7 | 3.3.3.2 | 5.4 | {6.5.4.3 | 4.3 | 5.4.8.7 | 3 | 7 | 3 | 7 | 1: 2.33 | | | | | | | | | {2.1.5.8 | | | | | | | | | | | | | | | | | | | | | | | 28 | 51- 60 | 8 | 4.4.3 | 7.6 | 5 | 5.6.7 | 3.3.3.2 | 4 | {5.4.3 | 4.3 | {5.4.3.3.4.5 | 3 | 7 | 3 | 7 | 1: 2.33 | | | | | | | | | {3.6.8 | | {6.4.3.5.7 | | | | | | | | | | | | | | | | | | | | | 29 | 61- 70 | 8 | 4.3 | 6 | 6.6.5 | 7 | 3.3.3.2 | 5.4 | 7.6.4.7.6.8 | 4.3 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 31 | 71- 80 | 8 | 4.4.4.3 | 6 | 6.5 | 6.8.7 | 3.2 | 5.4 | {6.7.6.4.3 | 4.3 | 6.7 | 2 | 8 | 2 | 8 | 1: 4.00 June | | | | | | | | | {2.6.3.7.8 | | | | | | | | | | | | | {6.8.6.5.4 | | | | | | | | | | 1 | 81- 90 | 8 | 4.3 | 6 | 5 | {6.5.6.5.8 | 3.1.3.2 | 5.4 | 8 | 4.3 | 7 | 5 | 5 | | | | | | | | | {5.4.6.4.7 | | | | | | | | | | | | | | | | | | | | | | | | | | " | 91- 100 | 9.7.8 | 4.2.4.3 | 7.5.6 | 5 | 6.8.7 | 3.3.1.2 | 5.3.4 | 8 | 4.3 | 6.8.7 | 2 | 8 | 7 |13 | 1: 1.86 2 | 101- 110 | 8 | 4.3 | 6 | 5 | 7 | 3.2 | 5.4 | 7.8 | 4.3 | 6.8.6.5.7 | 4 | 6 | | | | | | | | | | | | | | | | | | | " | 111- 120 | 8 | 4.3 | 7.3.5.7.6 | {6.2.3.6.4 | 7 | 3.2 | {5.2.3.5.3.2 | 9.6.4.7.8 | {4.1.2 | 6.8.7 | 2 | 8 | 6 |14 | 1: 2.33 | | | | | {3.6.2.5 | | | {3.5.2.3.4 | | {4.2.3 | | | | | | | | | | | | | | | | | {6.8.6.3 | | | | | 3 | 121- 130 | 8 | 4.4.3 | 6 | 5 | 6.7 | 3.2 | {5.3.2.3 | 8 | 4.2.3 | {5.4.5.8.8 | 4 | 6 | | | | | | | | | | | {5.2.5.4 | | | {6.3.8.7 | | | | | | | | | | | | | | | | | | | | | " | 131- 140 | 8 | 4.3 | 5.7.3.2.6 | 4.5 | 5.7 | 1.3.2 | 5.3.4 | 6.7.8 | 4.2.1.3 | 7 | 2 | 8 | 6 |14 | 1: 2.33 | | | | | | | | | | | | | | | | 4 | 141- 150 | 8 | 4.3 | 7.6 | 6.5 | 7 | 2 | {5.3.2.3 | 6.8 | 4.1.3 | 5.6.7 | 3 | 7 | | | | | | | | | | | {5.5.4 | | | | | | | | | | | | | | | | | | | | | | | | " | 151- 160 | 8 | 4.3 | 6 | 5 | 6.7 | 2 | 4 | 5.6.7.8 | 4.3 | 5.6.8.7 | 5 | 5 | 8 |12 | 1: 1.50 5 | 161- 170 | 8 | 4.3 | 7.6 | 6.5 | 6.8.7 | 3.2 | 5.3.2.3.5.4 | 8 | 4.3 | 6.7 | 2 | 8 | | | " | 171- 176 | 8 | 2.4.3 | 7.6 | 6.5* | 8.7 | 3.2* | | | | | 1 | 5 | 3 |13 | 1: 4.33 7 | 177- 180 | | | | | | | 5.4 | 8 | 4.4.3 | 8.7 | 1 | 3 | | | " | 181- 190 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.3.2.5.4 | 8 | 4.3 | 7 | 4 | 6 | 5 | 9 | 1: 1.80 8 | 191- 200 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 2 | 8 | | | " | 201- 210 | 8 | 4.3 | 6 | 6.4.6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 4 | 6 | 6 |14 | 1: 2.33 9 | 211- 220 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.6.7 | 2 | 8 | | | " | 221- 230 | 9.8 | 4.3 | 7.6 | 6.5 | 6.7 | 3.2 | 5.4 | 7.6.8 | 4.3 | 7 | 1 | 9 | 3 |17 | 1: 5.67 | | | | | | | | | | | | | | | | 10 | 231- 240 | 8 | 4.3 | 7.6 | 6.5 | 6.7 | 3.2 | 5.4 | {3.2.3.2.4.3 | 4.3 | 7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | | | {2.5.4.7.8 | | | | | | | | | | | | | | | | | | | | | | | 11 | 241- 250 | 8 | 4.3 | 7.6 | 6.6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | | | | | | | | | | 12 | 251- 260 | 8 | 4.3 | 6 | 6.5 | 6.7 | 3.3.2 | 5.4 | {7.6.7.7 | 3 | 3.7* | 3 | 7 | 3 | 7 | 1: 2.33 | | | | | | | | | {6.9.8* | | | | | | | | | | | | | | | | | | | | | | | 14 | 261- 270 | 8 | 3 | 6 | 6.5 | 7 | 3.2 | 5.4 | {5.3.4.3 | 3 | {3.3.3.3.4 | 5 | 5 | 5 | 5 | 1: 1.00 | | | | | | | | | {9.8* | | {4.6.4.7* | | | | | | | | | | | | | | | | | | | | | 15 | 271- 280 | 7.9.8 | 4.2.3 | 3.4.3.7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 1 | 9 | | | " | 281- 290 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 7.8 | 4.3 | 7 | 3 | 7 | 4 |16 | 1: 4.00 | | | | | | | | | | | | | | | | | | | | | | | | | {4.3.2.3 | | | | | | | 16 | 291- 300 | 7.8 | {4.4.4 | 6 | 6.5 | 7 | 3.3.2 | 5.4 | {6.5.4.3 | 4.3 | 6.7 | 2 | 8 | | | | | | {4.4.3 | | | | | | {5.6.7.8 | | | | | | | | | | | | | | | | | | | | | | | " | 301- 310 | 8 | 4.4.3 | 7.6 | 6.5 | 7 | 3.3.2 | 5.5.4 | {7.6.5.4.6 | 4.3 | 7 | 3 | 7 | 5 |15 | 1: 3.00 | | | | | | | | | {5.7.9.8 | | | | | | | | | | | | | | | | | | | | | | | 17 | 311- 320 | 7.8 | 4.3 | 7.6 | 6.6.5 | 7 | 3.2 | 5.4 | 7.6.7.6.7.8 | 4.3 | 7 | 2 | 8 | | | " | 321- 330 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 6.7 | 2 | 8 | 4 |16 | 1: 4.00 18 | 331- 340 | 7.7.8 | 4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 4 | 6 | | | " | 341- 350 | 8 | 4.3 | 7.6 | 6.6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 3 | 7 | 7 |13 | 1: 1.86 19 | 351- 360 | 8 | 4.3 | 7.6 | 6.5 | 6.5.6.5.7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 3 | 7 | | | " | 361- 370 | 8 | 4.3 | 7.6 | 6.4.3.6.5 | 7 | 3.2 | 5.4 | 9.8 | 4.3 | 7 | 3 | 7 | 6 |14 | 1: 2.33 21 | 371- 380 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 7.8 | 4.3 | 8.7 | 2 | 8 | | | " | 381- 390 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 4 | 6 | 6 |14 | 1: 2.33 22 | 391- 400 | 8 | 4.3 | 7.6 | 6.5 | 6.5.4.6.7 | 3.3.3.2 | 5.4 | 6.7.8 | 4.4.3 | 7 | 2 | 8 | | | " | 401- 410 | 8 | 3 | 7.6 | 6.5 | 8.7 | 2 | 5.4 | 6.7.7.8 | 3 | 7 | 5 | 5 | 7 |13 | 1: 1.86 | | | | | | | | | | | | | | | | 23 | 411- 420 | 8 | 4.4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | {7.6.7.6 | 4.3 | 7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | | | {6.7.8 | | | | | | | | | | | | | | | | | | | | | | | 24 | 421- 430 | 8 | 4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 3 | 7 | 6 | 4 | | | " | 431- 440 | 8 | 3 | 7.6 | 6.5 | 7 | 3.3.2 | 5.4 | 8 | 4.3 | 7 | 5 | 5 |11 | 9 | 1: 0.82 25 | 441- 450 | 7.8 | 4.4.3 | 7.6 | 6.5 | 6.5.7 | 3.3.2 | 5.5.4 | 7.8 | 4.3 | 7 | 1 | 9 | 1 | 9 | 1: 9.00 26 | 451- 460 | 7.8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 3 | 7 | | | " | 461- 470 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 3 | 7 | 6 |14 | 1: 2.33 28 | 471- 480 | 8 | 4.4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 9.8 | 3 | 8.7 | 3 | 7 | 3 | 7 | 1: 2.33 29 | 481- 490 | 8 | 4.3 | 7.7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 3 | 7 | 3 | 7 | 1: 2.33 30 | 491- 500 | 7.9.8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 3 | 7 | | | " | 501- 510 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.4.3 | 8.7 | 2 | 8 | 5 |15 | 1: 3.00 July | | | | | | | | | | | | | | | | 1 | 511- 520 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 2 | 521- 530 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | {7.6.5.6.5 | 4.4.3 | 7 | 3 | 7 | | | | | | | | | | | | {6.5.6.8 | | | | | | | | | | | | | | | | | | | | | | | " | 531- 540 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 4 | 6 | 7 |13 | 1: 1.86 3 | 541- 550 | 7.8 | 4.4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 5.5.7 | 3 | 7 | | | " | 551- 560 | 7.8 | 4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 3 | 7 | 5 | 5 | 8 |12 | 1: 1.50 5 | 561- 570 | 7.7.8 | 4.3 | 6 | 6.5 | 6.7 | 3.3.2 | 5.4 | 8 | 4.3 | 7 | 3 | 7 | | | " | 571- 580 | 8 | 4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 7.8 | 4.3 | 7 | 4 | 6 | 7 |13 | 1: 1.86 | | | | | | | | | | | | | | | | | | | | | | {6.5.4.6.5 | | | | | | | | | | 6 | 581- 590 | 7.8 | 4.3 | 7.6 | 6.6.5 | {5.4.5.4.4 | 2 | 3.4 | 6.5.4.3.7.8 | 3 | 7 | 3 | 7 | 3 | 7 | 1: 2.33 | | | | | | {6.5.6.5.8.7 | | | | | | | | | | | | | | | | | | | | | | | | | | 7 | 591- 600 | 8 | 4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 7.8 | 4.3 | 8.7 | 3 | 7 | | | " | 601- 610 | 7.8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 1 | 9 | 4 |16 | 1: 4.00 8 | 611- 620 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 2 | 8 | | | " | 621- 630 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 9.8 | 4.3 | 8.7 | 1 | 9 | | | " | 631- 640 | 8 | 4.4.3 | 7.7.6 | 6.5 | 8.7 | 3.2 | 4 | 8 | 4.3 | 8.7 | 3 | 7 | 6 |24 | 1: 4.00 | | | | | | | | | | | | | | | | 9 | 641- 650 | 7.8 | 4.3 | 7.6 | 6.5 | 6.7 | 3.2 | {3.2.5.3 | 7.6.5.4.8 | 3 | 8.7 | 1 | 9 | 1 | 9 | 1: 9.00 | | | | | | | | {2.5.4 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {6.5.4.3.7 | | | | | | | 10 | 651- 660 | 7.8 | 4.3 | 6 | 6.5 | 7 | 3.2 | 5.4 | {6.5.4.7.6 | 4.3 | 7 | 3 | 7 | | | | | | | | | | | | {5.4.8 | | | | | | | | | | | | | | | | | | | | | | | 10 | 661- 670 | 8 | 3 | 7.6 | 5 | 7 | 3.2 | 5.4 | 8 | 3 | 8.7 | 6 | 4 | 9 |11 | 1: 1.22 12 | 671- 680 | 7.8 | 3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 6.5.4.7.8 | 4.3 | 8.7 | 3 | 7 | 3 | 7 | 1: 2.33 | | | | | | | | | | | | | | | | 13 | 681- 690 | 8 | 3 | 7.6 | 6.5 | {6.5.4 | 3.2 | 4 | 6.7.8 | 3 | {6.5.4.5 | 4 | 6 | | | | | | | | | {6.5.7 | | | | | {6.5.8.7 | | | | | | | | | | | | | | | | | | | | | " | 691- 700 | 8 | 3 | 6 | 5 | 7 | 3.2 | 5.4 | 8 | 3 | 7 | 8 | 2 |12 | 8 | 1: 0.67 | | | | | | | | | | | | | | | | 14 | 701- 710 | 8 | 3 | 7.6 | 6.5 | {6.5.4.5 | 2 | 3.5.4 | 8 | 3 | 7 | 6 | 4 | | | | | | | | | {4.6.8.7 | | | | | | | | | | " | 711- 720 | 8 | 3 | 6 | 5 | 7 | 2 | 5.4 | 6.5.4.8 | 3 | 6.5.7 | 7 | 3 |13 | 7 | 1: 0.54 15 | 721- 730 | 7.8 | 3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 4.3 | 7 | 5 | 5 | | | " | 731- 740 | 8 | 3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 3 | 7 | 6 | 4 |11 | 9 | 1: 0.82 16 | 741- 750 | 7.8 | 3 | 6 | 6.5 | 7 | 3.2 | 4 | 8 | 3 | 7 | 7 | 3 | | | " | 751- 760 | 7.8 | 3 | 7.6 | 6.5 | 7 | 2 | 4 | 7.8 | 4.3 | 7 | 5 | 5 |12 | 8 | 1: 0.67 17 | 761- 770 | 8 | 4.3 | 6 | 5 | 8.7 | 3.2 | 5.4 | 8 | 4 | 7 | 6 | 4 | | | " | 771- 780 | 8 | 2.2.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 7.8 | 4.3 | 7 | 3 | 7 | 9 |11 | 1: 1.22 19 | 781- 790 | 8 | 3 | 7.6 | 5 | 7 | 3.2 | 3.4 | 7.6.5.8 | 3 | 7 | 6 | 4 | | | " | 791- 800 | 7.8 | 3 | 6 | 5 | 7 | 2 | 5.4 | 8 | 3 | 6.5.6.7 | 7 | 3 | | | " | 801- 810 | 8 | 2.3 | 6 | 5 | 6.5.7 | 2 | 5.4 | 8 | 3 | 7 | 7 | 3 |20 |10 | 1: 0.50 20 | 811- 820 | 7.8 | 3 | 7.6 | 5 | 7 | 3.3.2 | 5.4 | 8 | 2.2.3 | 7 | 5 | 5 | | | " | 821- 830 | 8 | 3 | 6 | 6.5 | 7 | 3.2 | 4 | 8 | 2.3 | 8.7 | 6 | 4 |11 | 9 | 1: 0.82 21 | 831- 840 | 8 | 3 | 5.4.5.6 | 5 | 7 | 2 | 4 | 6.7.8 | 3 | 8.7 | 7 | 3 | | | " | 841- 850 | 8 | 3 | 7.6 | 5 | 7 | 3.2 | 3.2.4 | 8 | 3 | 7 | 7 | 3 |14 | 6 | 1: 0.43 22 | 851- 860 | 8 | 4.3 | 6 | 5 | 7 | 3.2 | 3.5.4 | 8 | 3 | 8.7 | 6 | 4 | | | " | 861- 870 | 7.8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 4 | 8 | 3 | 8.7 | 3 | 7 | | | " | 871- 880 | 8 | 4.3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 4.3 | 8.7 | 2 | 8 |11 |19 | 1: 1.73 23 | 881- 890 | 8 | 3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.4 | 8 | 3 | 8.7 | 4 | 6 | | | " | 891- 900 | 8 | 3 | 7.6 | 6.5 | 7 | 3.3.2 | 5.4 | 8 | 4.3 | 7 | 5 | 5 | 9 |11 | 1: 1.22 24 | 901- 910 | 8 | 4.3 | 7.6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 3 | 8.7 | 4 | 6 | | | " | 911- 920 | 8 | 3 | 7.6 | 5 | 7 | 3.2 | 5.4 | 8 | 3 | 7 | 7 | 3 |11 | 9 | 1: 0.82 26 | 921- 930 | 7.8 | 3 | 7.6 | 5 | 7 | 3.2 | 5.4 | 8 | 2.2.3 | 8.7 | 4 | 6 | | | " | 931- 940 | 8 | 3 | 7.6 | 6.5 | 8.7 | 3.2 | 5.5.4 | 8 | 4.3 | 8.7 | 3 | 7 | 7 |13 | 1: 1.86 27 | 941- 950 | 8 | 3 | 6 | 6.5 | 7 | 3.2 | 5.4 | 8 | 3 | 7 | 7 | 3 | 7 | 3 | 1: 0.43 28 | 951- 960 | 8 | 3 | 7.6 | 6.5 | 5.4.7 | 2 | 5.5.4 | 8 | 3 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 29 | 961- 970 | 8 | 3 | 7.6 | 5 | 8.7 | 2 | 4 | 8 | 3 | 7 | 8 | 2 | 8 | 2 | 1: 0.25 | | | | | | | | | | | | | | | | 30 | 971- 980 | 8 | 3 | 4.3.2.6 | 5 | {6.5.4.6 | 2 | 5.5.4 | 8 | 3 | 7 | 7 | 3 | 7 | 3 | 1: 0.43 | | | | | | {6.5.7 | | | | | | | | | | | | | | | | | | | | | | | | | | 31 | 981- 990 | 8 | 3 | 6 | 6.5 | 8.7 | 2 | 4 | 8 | 3 | 7 | 8 | 2 | 8 | 2 | 1: 0.25 August | | | | | | | | | | | | | | | | 2 | 991-1000 | 8 | 3 | 7.6 | 5 | 7 | 2 | {2.3.5.3 | 7.6.8 | 3 | 7 | 7 | 3 | 7 | 3 | 1: 0.43 | | | | | | | | {2.3.3.4 | | | | | | | | | | | | | | | | | | | | | | | | 3 | 1001-1010 | 8 | 3 | 7.6 | 5 | 7 | 2 | 4 | 7.6.5.6.7.8 | 3 | 5.4.3.4.3.7 | 7 | 3 | | | " | 1011-1020 | 8 | 2.3 | 5.6 | 3.2.3.6.5 | 7 | 2 | 5.4 | 9.8 | 2.1.3 | 7 | 4 | 6 |11 | 9 | 1: 0.82 | | | | | | | | | | | | | | | | 4 | 1021-1030 | 7.8 | 3 | 5.4.3.7.6 | 6.5 | {6.5.6 | 3.2 | 5.4 | 8 | {2.2.4.2 | 8.7 | 2 | 8 | | | | | | | | | {5.6.7 | | | | {4.2.3 | | | | | | | | | | | | | | | | | | | | | | " | 1031-1040 | 7.8 | 3 | 6 | 6.4.3.6.5 | 7 | 2 | 3.5.4 | 8 | 2.3 | 8.7 | 5 | 5 | 7 |13 | 1: 1.86 | | | | | | | | | | | | | | | | 5 | 1041-1050 | 8 | 3 | 6 | 2.3.2.6.5 | 8.7 | 2 | 4 | 8 | 2.2.4.3 | {8.8.6.8.4 | 6 | 4 | 6 | 4 | 1: 0.67 | | | | | | | | | | | {6.5.8.7 | | | | | | | | | | | | | | | | | | | | | 6 | 1051-1060 | 8 | 3 | 6 | 4.2.6.5 | 7 | 3.2 | 5.4 | 8 | 3 | 8.7 | 6 | 4 | 6 | 4 | 1: 0.67 | | | | | | | | | | | | | | | | 7 | 1061-1070 | 8 | 3 | 5.4.3.6 | 4.5 | {6.5.6.5 | 2 | 4 | 8 | 3 | 7 | 7 | 3 | 7 | 3 | 1: 0.43 | | | | | | {4.8.7 | | | | | | | | | | | | | | | | | | | | | | | | | | 9 | 1071-1080 | 8 | 3 | 6 | 5 | 7 | 2 | 4 | 8 | 3 | 7 |10 | 0 |10 | 0 | 1: 0.00 ————+—————-+———————+———————+———————+———————+———————+———————+———————+———————+———————+———————+—-+—-+—-+—-+———— | | | | 1.2.3.4.5 | | | | | | 1.2.3.4 | 2.3.4.5 | | | | | | | 5.6.7.8 | 2.3.4.5.6 | 6.7.8.9 | 5.6.7 | 1.2.3.4 | 4.5.6 | 2.3.4.5 | 1.2.3 | 5.6.7 | 6.7.8.9 | | | | | ————+—————-+———————+———————+———————+———————+———————+———————+———————+———————+———————+———————+—-+—-+—-+—-+———— 10 | 1- 10 | 6.5.7 | 3.2.6.5 | 8 | 6 | 2.4.3 | 5 | 5.4 | 2 | 7.5.2.7.6 | 8 | 5 | 5 | 5 | 5 | 1: 1.00 11 | 11- 20 | 7 | 3.6.5 | 8 | 6 | 3 | 6.5 | 4 | 3.2 | 7.6 | 8 | 6 | 4 | 6 | 4 | 1: 0.67 | | | | | | | | | | | | | | | | | | | | | | | | {3.2.3.5.3 | | | | | | | | 12 | 21- 30 | 7 | 2.2.6.5 | 7.8 | 6 | 3 | 5 | {2.5.3.2 | 2 | 6 | 8 | 7 | 3 | 7 | 3 | 1: 0.43 | | | | | | | | {5.3.2.5 | | | | | | | | | | | | | | | | {2.5.5.4 | | | | | | | | | | | | | | | | | | | | | | | | ========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========

[Footnote 1: First choices correct by reason of aid from the experimenter are not counted as correct (R) in the summary.]

[Footnote *: Aided by experimenter.]

The method of choosing the first box at the right end and then the one next to it developed in the case of all except two of the ten settings. The time of appearance is worth noting. In setting 1, it failed to appear; in setting 2, it developed early,—after about one hundred trials; in setting 3, after about one hundred and fifty trials; in setting 4, after about one hundred and fifty trials; in setting 5, after about one hundred and seventy trials; in setting 6, after about one hundred trials; in setting 7, after about fifty trials; in setting 8, it never developed; in setting 9, after about fifty trials; and in setting 10, it developed very late,—after about four hundred and seventy trials.

This method of reaction, although inadequate, proved remarkably persistent, and it is doubtful whether it had been wholly overcome at the conclusion of the experiment. In the case of the series of trials given on June 8, numbered 191 to 200, the method used was either that of the first at the right and then the next, or direct choice of the right box.

Throughout the trials with this problem, the end boxes, numbers 1 and 9, were avoided. This is at least partially explained by the fact that they never existed, and obviously never could appear, in problem 2, as right boxes. In trials 601 to 610, given on July 7, there occurred partial return to the formerly established method of choosing the first door at the right. This relapse was characteristic of what happened during the many days which intervened between the definite appearance of this habit and the final solution of the problem.

Especially in connection with such relapses, Skirrl showed extreme fatigue or ennui and often would refuse to work and simply sit before the open doors yawning. This happened even when he was extremely hungry and evidently eager enough for food.

From July 12 on the hunger motive was increased by feeding the monkey only in the apparatus and by so regulating the amount of food given in each trial that he should obtain barely enough to keep him in good physical condition. An increase in the number of correct choices promptly resulted, and continued until on July 14 the ratio of choices was 1 to .54. It appeared from these data that a relatively small number of choices, say not more than ten a day, the rewards in connection with which supplied the only food received by the animal, yielded most favorable results.

On July 16, the period of confinement in wrong boxes was increased to sixty seconds, and it was so continued for a number of days. But in the end, it became clear that the period of thirty seconds, combined with a liberal reward in the shape of desired food and a single series of ten trials per day, was most satisfactory. The detailed data of table 2 indicate that at this time Skirrl was making his choices by memory of the particular setting.

Skirrl, on July 17 was evidently hungry and eager to locate food, but seemingly unable to select the right box. In trial 5 (765th) of the series, he was punished by confinement in box 8. When the doors were unlocked in order that the entrance door might be raised to release him, the lock-bar, sliding under the floor, made a slight grating noise, and the instant the entrance door was opened, he jumped out excitedly.He made no outcry, but as soon as he was out of the box, sat down, and taking up his right hind foot, examined it for a few seconds.Having apparently assured himself that nothing serious had happened, he went on unconcernedly about his task. The presumption is that the sound of the lock-bar, associated as it was with his painful experience in box 1, revived the strongly affective experience of stepping on the nail. Psychologically described, the sound induced an imaginal complex equivalent to the earlier painful experience. The behavior seems to the writer a most important bit of evidence of imagery in the monkey. Finally, on August 9, after ten hundred and seventy trials, Skirrl succeeded in choosing correctly in the ten trials of a series, and he was therefore considered to have solved the problem of the second door from the right end of the group.

On the following day, he was given a control series with the settings which are presented on page 19 and also at the bottom of table 2. In this series he chose correctly five times,—in other words, as often correctly as incorrectly. An analysis of the choices indicates, however, that two of the five correct choices were made in box 8, which, as it happened, had proved a peculiarly easy one for him throughout the training, since from the first he tended to avoid door 9. Consequently, it is only fair to conclude, from the results for this control series and for those given on August 11 and 12, that the animal chose not on the basis of anything remotely resembling a general idea of secondness from the right end, but instead on the basis of gradually acquired modes of reaction to the particular settings. This conclusion is strengthened by the fact that he had failed to learn to react appropriately and readily to most of the settings of the regular series.

The curve which represents the course of the learning process in this problem is presented in figure 19. For this and all other curves which involve more than a single series of observations a day, the method of construction was as follows: The first series for each day of training is indicated on the curve by a dot, while the second or third series on a given day, although space is allowed for them, are not so indicated. Consequently, the form of the curve is determined chiefly by the first series per day. The extreme irregularities of this curve are most interesting and puzzling, as are also the variations in the daily ratios of right to wrong first choices. Three times in the course of the training, this ratio rose to 1 to 9, or higher. The causes for such extreme variations are not easily enumerated, but a few of the most obvious contributory causes are variations in the weather, especially cloudiness or fogginess, which rendered the apparatus dark; variations in the degree of hunger or eagerness for food; differences in the activities of the animals in the cages outside of the laboratory (sometimes they were noisy and distracted the subject), and finally, differences in the physical fitness and attitude of the animal from day to day.

The more or less incidental behavior in connection with this experiment more strongly than the statistical results of the work on problem 2 indicate the existence of imagery. That ideas played a part in the solution of the problem is probable, but at best they functioned very ineffectively. The small number of methods used in the selection of the right box, and the slight variations from the chief method, that of choosing the first box at the right end and then the one next to it, apparently justify Doctor Hamilton's characterization of this monkey as defective.

[Illustration: FIGURE 19.—Error curves of learning for the solution of problem 2 (second box from right end).]

Problem 3. Alternately First at Left and First at Right

Following the control series given in connection with problem 1, an interval of rest lasting from August 12 to August 19 was allowed in order that Skirrl might in part at least lose the effects of his training and regain his customary interest in the apparatus by being allowed to obtain food easily instead of by dint of hard labor,—labor which was harder by far, apparently, than physical activity because it demanded of the animal certain mental processes which were either lacking or but imperfectly functional. The difficultness of the daily tasks appears to be reliably indicated by the tendency to yawn.

Systematic work on problem 3, which has been defined as alternately the first door at the left and the first door at the right of the group, was begun August 19, and for nine days a single series of ten trials per day was given. Work then had to cease because of the experimenter's return to Cambridge.

The results of the work on this problem demand but brief analysis and comment. The expected ratio of one right to four wrong choices per series appears (see table 3) for the first series of trials, andthis in spite of the fact that Skirrl had been trained for several weeks to choose the second door from the right end. One would ordinarily have predicted a much larger number of incorrect choices. The right choices were due to the monkey's strong tendency to go first to the first door at the right and thence to the one next to it. Indeed in the series given on August 24; this method was followed without variation. In other words, in every one of the ten trials Skirrl entered first the box at the extreme right end of the group. This necessarily resulted in as many right as wrong first choices. Consequently, the ratio reads 1 to 1. But the method was not adhered to, and at no time either before or after that date did he succeed in equalling this achievement. There was, as a matter of fact, no steady improvement, and so far as one may judge from the records which were obtained, the course of events in the solution of this problem would have been similar to those in problem 2.

Results for Skirrl,P. irus, in Problem 3

========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+======== Date | No. of | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | R | W | R | W |Ratio of | trials | 5.6.7 | 5.6.7 | 1.2.3.4.5.6 | 1.2.3.4.5.6 | 4.5.6.7.8 | 4.5.6.7.8 | 2.3.4.5 | 2.3.4.5 | 3.4.5.6.7.8.9| 3.4.5.6.7.8.9| | | | |R to W ________|___________|______________|______________|______________|______________|______________|______________|______________|______________|______________|______________|___|___|___|___|________ August | | | | | | | | | | | | | | | | | | | | {6.5.4.6 | | | | | | | {8.7.6.5 | | | | | 19 | 1- 10 | 7.5 | 6.7 | {3.2.6.4 | 5.3.6 | {7.8.7.6 | 8 | 4.3.5.4.5.2 | 5 | 9.8.7.6.4.3 | {4.5.8.7 | 2 | 8 | 2 | 8 | 1:4.00 | | | | {3.6.1* | | {8.6.4 | | | | | {6.5.9* | | | | | | | | | | | | | | | | | | | | | | | | | {5.4.6.5 | | {8.7.6.7 | | | | | | | | | | 20 | 11- 20 | 7.6.5 | {6.5.6.5 | {4.6.5.3 | 5.3.2.4.6 | {7.5.8.8 | 8 | 5.4.3.2 | 4.5 | 8.7.6.5.4.3 | {8.7.6.8.3 | 1 | 9 | 1 | 9 | 1:9.00 | | | {7 | {2.5.1* | | {7.6.4* | | | | | {7.6.4.3.9 | | | | | | | | | | | | | | | | | | | | | | | | | {6.2.5.6 | | | | {5.3.5.4 | | | | | | | | 21 | 21- 30 | 7.6.7.6.5 | 7 | {5.3.6.5 | 2.5.5.6 | 8.6.5.4 | 8 | {3.5.3.5 | 5 | {9.8.7.6 | 8.9 | 3 | 7 | 3 | 7 | 1:2.33 | | | | {4.3.1* | | | | {4.3.2* | | {5.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 23 | 31- 40 | 7.6.5 | 6.5.7 | {6.4.3.2 | 3.2.6 | 8.7.6.4 | 8 | 5.4.5.3.2 | 5.2 | 8.7.3 | 9 | 2 | 8 | 2 | 8 | 1:4.00 | | | | {5.6.2.1 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 24 | 41- 50 | 7.6.5 | 7 | {6.2.5 | 6 | {8.7.8.7 | 8 | 5.3.2 | 5 | {9.8.7.6 | 9 | 5 | 5 | 5 | 5 | 1:1.00 | | | | {4.3.1 | | {5.7.5.4 | | | | {5.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {8.7.3.6 | | | | | 25 | 51- 60 | 7.6.5 | 6.5.7 | 5.2.1 | 6 | 8.5.4 | 8 | 2 | 2.5 | 9.8.7.4.3 | {8.7.5.3 | 3 | 7 | 3 | 7 | 1:2.33 | | | | | | | | | | | {8.7.9* | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 26 | 61- 70 | 7.6.5 | 6.5.7 | 1 | 2.1.6 | 8.7.6.4 | 8 | 2 | 3.2.5 | 9.8.7.5.3 | {3.6.8.3 | 3 | 7 | 3 | 7 | 1:2.33 | | | | | | | | | | | {4.7.9 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {8.6.3.3 | | | | | 27 | 71- 80 | 7.6.5 | 7 | 2.1 | 1.5.6 | 8.7.6.4 | 8 | 2 | 5 | 9.8.7.6.3 | {7.5.3.8 | 4 | 6 | 4 | 6 | 1:1.50 | | | | | | | | | | | {3.6.9* | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 28 | 81- 90 | 7.6.7.5 | 7 | 3.1 | 6 | 8.6.4 | 4.8 | 2 | 2.4.5 | 8.7.4.3 | 3.8.9 | 3 | 7 | 3 | 7 | 1:2.33 | | | | | | | | | | | | | | | | ========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========

[Footnote *: Aided by experimenter.]

2. Sobke,Pithecus rhesus

Problem 1. First at the Left End

Sobke was somewhat afraid of the experimenter when the investigation was undertaken, and instead of willingly coming out of his cage when the door was raised, he often had to be coaxed out and lured into the apparatus with food. Whereas Skirrl was frank and rather aggressive, Sobke was stealthy in his movements, furtive, and evidently suspicious of the experimenter as well as of the apparatus. He was perfectly safe to approach, but would not permit anyone to touch him. After a few days, he began to take food from the hands of the experimenter.

Preliminary work to acquaint this monkey with the routine of the experiment was begun on April 13. As in the case of Skirrl, he was lured into the apparatus and was taught the route through the boxes to the starting point by being allowed to obtain food once each day in each of the nine boxes. The procedure was simple. The entrance door and the exit door of a particular box were raised and the animal admitted to the reaction-compartment and permitted to pass through the box whose doors stood open, take its food, and return to the starting point. Sobke very quickly learned the route perfectly and came to work steadily and rapidly. After five days of preliminary work of this sort, he was so thoroughly accustomed to the apparatus that it was evidently desirable to begin with regular training experiments.

The first series of trials was given on April 19. Both punishment and reward were employed from the first. The punishment consisted of confinement for thirty seconds in each wrong box, and the reward of a small piece of banana, usually not more than a tenth of a medium sized banana for each correct choice. The total time for the first series of trials was fourteen minutes. This indicates that Sobke worked rapidly. My notes record that he worked quickly though shyly, wasted almost no time, made few errors of choice, and waited quietly during confinement in the boxes. In this, also, he differed radically from Skirrl who was restless and always tried to escape from confinement.

Throughout the work on problem 1, punishment and reward were kept constant. Everything progressed smoothly; there were no such irregularities of behavior as appeared in the case of Skirrl, and consequently the description of results is a relatively simple matter. Sobke invariably chose the end boxes. His performance was in every way superior to that of Skirrl.

As previously, the detailed results are presented in tabular form (table 4). From this table it appears that, whereas the expected ratio of right to wrong first choices for this problem is 1 to 2.5, the actual ratio for Sobke's first series was 1 to .67. This surprisingly good showing is unquestionably due to his marked tendency to choose the end box of a group; and this tendency, in turn, may in part be the result of the preliminary training, for during that only one box was open each time. But, if the preliminary training were responsible for Sobke's tendency, it should be noted that it had very different effect upon Skirrl, and, as will be seen later, upon Julius.

The results for the ten different settings of the doors for problem 1 as they appear in table 4 are of interest for a number of reasons. In the first place, the setting 1. 2. 3 appearing twice,—at the beginning of the series and again at the end—yielded markedly different results in the two positions. For whereas no mistakes were made in the case of setting 1, there were fifty per cent of incorrect first choices for setting 10. Again, satisfactory explanation is impossible. It is conceivable that fatigue or approaching satiety may have had something to do with the failures at the end of the series, but as a rule, as is indicated by settings 1, 2, and 6, if correct choices were made at the beginning, they continued throughout the day's work.

In this problem, Sobke's improvement was steady and fairly rapid, and in the eighth series, trials 71 to 80, only correct first choices appear. Consequently, seventy trials were required for the solution of the problem. This number is in marked contrast with Skirrl's one hundred and thirty-two trials.

Immediately following the first perfect series, Sobke was given two series of control tests on April 28. Conditions were unfavorable, since the day was stormy and the rain pattering on the sheet-iron roof made a great din. Nevertheless, he worked steadily and well up to the sixth trial, which was preceded by a slight delay because of the necessity of refilling some of the food boxes. After this interruption, wrong choices occurred in trial 6. And again after trial 9, there was brief interruption, followed by wrong choices in trial 10. The ratio of right to wrong choices for this first control series was therefore 1 to .25.

Results for Sobke,P. rhesus, in Problem 1

========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========| No. | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | | | | | RatioDate | of | | | | | | | | | | | R | W | 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 | 8 | 3 | 9.7 | 6.2 | 6 | 7.5 | 4 | 9.7 | 1 | 6 | 4 | 6 | 4 | 1:0.6720 | 11-20 | 1 | 8 | 3 | 7 | 2 | 6 | 7.5 | 8.4 | 9.9.7 | 1 | 7 | 3 | 7 | 3 | 1:0.4321 | 21-30 | 1 | 8 | 4.3 | 9.7 | 2 | 6 | 5 | 8.4 | 7 | 1 | 7 | 3 | 7 | 3 | 1:0.4322 | 31-40 | 1 | 8 | 3 | 7 | 6.2 | 6 | 6.5 | 4 | 7 | 3.1 | 7 | 3 | 7 | 3 | 1:0.4323 | 41-50 | 1 | 8 | 3 | 7 | 2 | 6 | 5 | 4 | 9.7 | 3.1 | 8 | 2 | 8 | 2 | 1:0.2524 | 51-60 | 1 | 8 | 3 | 9.7 | 2 | 6 | 5 | 4 | 7 | 2.1 | 8 | 2 | 8 | 2 | 1:0.2526 | 61-70 | 1 | 8 | 3 | 7 | 2 | 6 | 5 | 4 | 7 | 3.1 | 9 | 1 | 9 | 1 | 1:0.1127 | 71-80 | 1 | 8 | 3 | 7 | 2 | 6 | 5 | 4 | 7 | 1 |10 | 0 |10 | 0 | 1:0.00————+—————-+———————+———————+———————+———————+———————+———————+———————+———————+———————+———————+—-+—-+—-+—-+————| | | | | | | | 2.3.4 | | | 1.2.3.4.5 | | | | || | 2.3.4 | 6.7.8.9 | 3.4.5 | 4.5.6.7.8.9 | 6.7.8.9 | 1.2.3.4.5 | 5.6.7.8 | 3.4.5.6.7.8 | 5.6.7 | 6.7.8.9 | | | | || +———————+———————+———————+———————+———————+———————+———————+———————+———————+———————+ | | | |28 | 1-10 | 2 | 6 | 3 | 4 | 6 | 5.4.1 | 2 | 3 | 5 | 5.4.2.1 | 8 | 2 | | |" | 11-20 | 2 | 6 | 3 | 4 | 6 | 2.1 | 2 | 3 | 5 | 1 | 9 | 1 |17 | 3 | 1:0.18| | | | | | | | | | | | | | | |========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========

Six minutes after completion of the first control series, a second was given under slightly more favorable conditions, and in this only a single wrong choice occurred, in that box 2 was first chosen in trial 6 instead of box 1. From the results of these two control series, it is evident that Sobke's solution of problem 1 is reasonably adequate. He is easily diverted or disturbed in his work by any unusual circumstances, but so long as everything goes smoothly, he chooses with ease and certainty. Whether it is fair to describe the behavior as involving an idea of the relation of the right box to the other members of the group would be difficult to decide. I hesitate to infer definite ideation from the available evidence, but I strongly suspect the presence of images and relatively ineffective or inadequate ideation.

It is perfectly evident that Sobke is much more intelligent than Skirrl. In practically every respect, he adapted himself more quickly to the experimental procedure and progressed more steadily toward the solution of the problem than did Skirrl. The contrast in the learning processes of the two monkeys could scarcely be better exhibited than by the curves of learning which are presented in figure 18. The first, that for Sobke, is surprisingly regular; the second, that for Skirrl, is quite as surprisingly irregular. These results correlate perfectly with the steadiness and predictability of the former's responses and the irregularity and erraticness of the latter's.

Problem 2. Second from the Right End

On the completion of problem 1 Sobke was in perfect condition, as to health and training, for experimental work. He had come to work quietly, fairly deliberately, and very steadily. His timidity had diminished and he would readily come to the experimenter for food, although still he was somewhat distrustful at times and became timid when anything unusual occurred in the apparatus.

As preparation for problem 2, a break in regular experimentation covering four days followed the control series of problem 1. On each of these four days the monkey was allowed to get food once from each of the nine boxes, both doors of a given box being open for the trial and all other doors closed. For this feeding experiment, the doors were opened in irregular order, and this order was changed from day to day.

Systematic work with problem 2 began on May 3, with punishment of thirty seconds for mistakes and a liberal reward of food for each success. Early in the series of trials it was discovered that Sobke was likely to become discouraged and waste a great deal of time unless certain aid were given by the experimenter. On this account, after the first two trials, the method was adopted of punishing the animal by confinement for the first ten mistakes in a trial, and of then, if need be, indicating the right box by slightly and momentarily raising the exit door. Every trial in which aid was thus given by the experimenter is indicated in table 5 by an asterisk following the last choice. In the first series of trials for this problem, aid had to be given in seven of the ten trials, and even so the series occupied seventy-one minutes. It is possible that had no aid been given, the work might have been continued successfully with a smaller number of trials than ten per day. But under the circumstances it seemed wiser to avoid the risk of discouraging and thus spoiling the animal for use in the experiment. It should be stated, also, that it proved impossible to adhere to the period of thirty seconds as punishment in this series. For the majority of the wrong choices confinement of not more than ten seconds was used.

For the second series, given on May 4, the conditions were unfavorable in that it was dark and rainy, and the noise of the rain on the roof frightened Sobke. He refused to work after the fourth trial, and the series had to be completed on the following day. The total time required for this series was seventy-eight minutes.

The work on May 6 was distinctly better, and the animal's behavior indicated, in a number of trials, definite recognition of the right door. He might, for example, make a number of incorrect choices, then pause for a few seconds to look steadily at the doors, and having apparently found some cue, run directly to the right box. No aid from the experimenter was needed in this series.

On the following day improvement continued and the animal's method of choosing became definite and fairly precise. He was deliberate, quiet, and extremely business-like. The time for the series was thirty-one minutes.

The period of punishment was increased on May 12 to thirty seconds. Previously, for the greater number of the trials, it had been ten to fifteen seconds. This increase apparently did not disturb the monkey, for he continued to work perfectly throughout the series, although making many mistakes in spite of deliberate choices and the refusal of certain boxes in each trial.

An interesting and significant incident occurred on May 13 when at the conclusion of trial 5, Doctor Hamilton came into the experiment room for a few minutes. Sobke immediately stopped working, and he could not be induced to make any choices until Doctor Hamilton had left the room. This well indicates his sensitiveness to his surroundings, and his inclination to timidity or nervousness even in the presence of conditions not in themselves startling.

Work was continued thus steadily until May 28 when, because of the failure of the animal to improve, it seemed wise to increase the period of confinement as punishment to sixty seconds. In the meantime, it had sometimes been evident that Sobke was near to the solution of his problem. He would often make correct choices in three or four trials in succession and then apparently lose his cue and fail utterly for a number of trials.

After June 1, in order to hasten the solution of the problem, two series per day were given. In some instances the second series was given almost immediately after the first, while in others an interval of an hour or more intervened. It was further found desirable to give Sobke all of his food in the apparatus. When the rewards obtained in the several trials did not satisfy his hunger, additional food was presented, on the completion of the series of experiments, in one or more of the food cups. On days marked by unwillingness or refusal to work, very little food was given. Thus, the eagerness of the monkey to locate the right box was increased and, as a matter of observation, his deliberateness and care in choice increased correspondingly. Sixty seconds punishment was found satisfactory, and it was therefore continued throughout the work on this problem.

It was evident, on June 9, from the behavior of the monkey as well as from the score, that the perfect solution of the problem was near at hand. This fact the experimenter recorded in his daily notes, and sure enough, on the following day Sobke chose correctly throughout the series of ten trials. The time for this series was only ten minutes. The choices were made deliberately and readily.

An analysis of the data of table 5 reveals five methods or reactive tendencies which appeared more or less definitely in the following order: (a) Choice of first box at the left, because of experience in problem 1. This tendency was very quickly suppressed by the requirements in connection with problem 2. Indeed one of the most significant differences which I have discovered between the behavior of the primates and that of other mammals is the time required for the suppression of such an acquired tendency. The monkey seems to learn almost immediately that it is not worth while to persist in a tendency which although previously profitable no longer yields satisfaction, whereas in the crow, pig, rat, and ring dove, the unprofitable mode of response tends to persist during a relatively large number of trials. (b) The tendency to choose, first, a box near the left end of the group, to go from that to the box at the extreme right end of the group, thence to the one next in order, which was, of course, the right box. This tendency appears fairly clearly from May 7th on. (c) The box at the extreme right was first chosen and then the one next to it. For example, in setting 2, box 4 would be chosen first, then box 3. Or, if this did not occur, the method previously described under (b) was likely to be employed, as for example, in setting 8, where such choices as 7.6.5.1.8 appear. (d) In certain series there appeared a marked preference for a particular box, usually box 3 (see results for May 24). This was doubtless due in a measure, if not wholly, to the fact that box 3 was the right box twice in each series of ten settings. But it should be added that the same is true of box 7, for which no preference was manifested at any time. (e) Direct choice of the right box.

The five reactive methods or tendencies enumerated above roughly appeared in the order named, but there were certain irregularities and the order as well as the time of appearance varied somewhat from setting to setting. In general, method c was the most frequently used prior to the development of method e, the direct choice of the right box.


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