EFFECT f)F LENGTH OF BLIND ALLEYS ON I\L\ZE LEARNING 49 



with distance through the maze and number of ciil dc sacs. 

 Peckstein found the whole maze over twenty times more difficult 

 than the average of the four quarter mazes, whereas such a 

 direct proportionate increase of difficultness as he assumed 

 should make it but four times more difficult. Of course, many 

 other factors in any such calculations must be taken into 

 consideration. With Peckstein' s rats the relative degrees of 

 difficultness of the four sections of the maze were found, in 

 order from the first to the fourth quarter, to be 15, 1, 3, 2, as 

 determined by his combined, trials-time-error formula. This 

 does not look much like equality. The excess-distance run by 

 the rats is certainly a factor as well worth while as any to con- 

 sider. Why was it not included' 



So far, then, Dr. Peckstein's results, as presented by himself, 

 seem roughly to agree with our own in supporting the view 

 that mere probability laws account for the original " choices " 

 of the untrained rat at the several bifurcations in the maze. 

 This is our own interpretation of his data, not his, it should be 

 stated. He merely seems to hold that there is some law of 

 diminishing returns, which he does not clearly state, that deter- 

 mines the degree of energy expended for the learning of mazes 

 of varying complexity. 



Dr. G. V. Hamilton in his interesting study of perseverance 

 reactions, by the multiple choice method as he has developed 

 it, finds frequency and recency of an advantageous response 

 more strongly effective toward learning than either frequency 

 or recency with no advantage or with actual disadvantage.-'. 

 He finds that frequency with invariable advantage is stronger 

 in effect toward the building of a habit than even greater fre- 

 quency without an invariable advantage. But, as in most 

 experiments on learning, he has his conditions so arranged that 

 the animal can end up only with the " successful " act." E. g., 

 Hamilton says: " During the twenty habit forming trials under 

 discussion she [Rat No. 1] manifested only three recency first 

 choices, but after these trials [that is, when the habit was learned] 

 during which the operation of the factor of recency was invariably 

 advantageous she manifested 100% of recency first choices. "2» 



'' A Study of Perseverance Reactions in Primates and Rodents. Behau. Mon., 

 Ser. No. 13, 1916. 

 28 Ibid., pp. 38-46. 

 23 Ibid., p. 40. 



