50 G. V. HAMILTON 



according as Door 4 or Door i is the unlocked door. Thus, if 

 Door I be unlocked, the subject tries the doors in the following 

 order: 4, 3, 2, i. 



Type D. More than a single continuous effort to open a 

 given door during the trial; but between separate efforts to 

 open the same door there must be an effort to open some other 

 door. Thus, the subject tries doors in the following order: 

 4, I, 4> 3; or 4, I, 2, 4, 3, etc. 



Type E. This type includes various highly inappropriate 

 modes of seeking escape from the apparatus which might be 

 classed as separate types of reaction were it not that when 

 collectively treated as a unit in the distribution curve they are 

 seen to belong to a single general type. The various forms of 

 Type E reactions are, — (a) during a given trial the subject 

 tries a door, leaves it, then returns to it and tries it a second 

 time without having tried any other door; (b) during a given trial 

 the subject attacks a group of two or three locked doors tw^o or 

 more times in a regular order; (c) during a given trial the sub- 

 ject, without falling into either of the above two errors of reac- 

 tion, persistently avoids an exit door, so that he makes at least 

 seven separate efforts to open exit doors before effecting his 

 escape. 



It is especially important to gain a clear understanding of 

 the objective characteristics of the classified types of reaction 

 described above, since they will appear as units in all of the 

 analyses that are to follow. Table 3, given below, contains 

 characteristic examples. 



TABLE 3 

 Examples of Classified Reactions 



Type E Ttjpe E 



4, 3, 4, 1 3, 3, 1 (sub-type a) 



2, 3, 4, 3, 2, 1 4, 2, 2, 2, 2, 1 (sub-type a) 



2, 4, 3, 2, 1 4, 2, 4, 2, 1 (sub-type b) 



3, 4, 2, 3, 4, 2, 3, 4, 2, 1 (sub-type b) 



4, 3, 2, 4, 2, 3, 1 (sub-type c) 



3, 4, 2, 4, 3, 2, 3, 4, 1 (sub-type c) 



Explanation of Table 3 — Each horizontally arranged group of figures describes 

 a single trial; and each figure in such a group refers to an exit door tried. Thus, 

 "4, 2, 3, 1" is descriptive of a trial during which the subject tried first to open door 

 4, following which he tried doors 2, 3 and 1 in the order given. The last figure 

 in each horizontally arranged group refers to the exit door which afforded escape 

 when the subject pushed against it. 



The examples under Type A obtain their true significance only when we assume 

 that they describe trials during which door 3 was the impossible door. 



