For the purpose of examination of the three conflicting hypotheses with regard to the spread of reward-effect-the Thorndike's, Zirkle's, and Jenkins-and-Sheffield's “guessing-sequence” hypothesis-the following experiment was carried out. Ss : 32 College students, divided equally into 4 groups A, B, C and D. Stimulus items : 18 Japanese nonsense, syllables. Response-materials : 9 simple figures (See Fig. 2). Number of trials : 9 times. Time-interval of responses : 3 seconds. The responses of the Ss of A and B groups were given reward-and-punishments respectively according to the ordinary experimental procedures. The Ss of C and D groups were requested, instead of rewarding, to keep using those response-materials which they first placed on some definite key stimulus items to the final trial (the“fixed” response), and, at the same time, in lieu of punishment, not of use the same response-materials twice to other many stimulus items (the “liquid” response). The Ss of Group C, in all trials, were shown a card, on which all of the 9 response-materials were arranged in an identical manner, and to each of the rest of the groups were shown a card of the response-materials on each trial on which materials were arranged in different ways (See Table 1). The key stimulus items of groups A, C and D were isolated from other stimulus items in terms of style of printed letters and of color. The principal results were as follows : 1. Percentage of repetition of Group A's correct responses was markedly more dominant than that of Group B's, but neither of the groups indicated any gradient of repetition in the incorrect responses neighboring the correct ones (See Table 3). 2. The “fixed” responses of Groups C and D were fully repeated, but Group C alone showed a gradient of repetition in the “liquid” responses behind the “fixed”ones (See Table 3). It is rightfully argued through these findings that, even though guessing of the Ss are likely affected by the spatial sequencehabits during the course of each trial, no repetition-gradient appeared in the incorrect or “liquid” responses under conditions in which the spatial sequence habits do not affect the guessing of the Ss during the course of any two continuous trials as a whole, though correct or “fixed” responses were fully repeated. On the basis of the results of the present experiment, findings of the many investigators have been carefully re-examined. The repetition-gradient of incorrect responses following the correct ones known as the spread of reward-effect appears neither to depend on the spread of reward-effect nor on the spread of isolation-effect of the correct responses. The gradient is the function of the degree of repetition of the correct responses and the degree to which the guessings are affected by sequence-habits (both in time and in space). Thus far, it is reasonably concluded that the “guessing-sequence” hypothesis is the most dependable.
7. Abstract 7. 1. Purpose : The present experiment was designed to consider what effect the number of inconsistent trials (the frequency of inconsistent rewards or punish-ments) exerts on the development and strength of response fixation. Some grades, therefore, were set up in an insoluble discrimination problem on the Lashley's jumping apparatus for certain length of time. 7. 2. Results. 7. 2. 1. First Experiment : Subjects showing random response entered, respectively, each insoluble problem situation. (Fig. 1) More subjects developed response-fixation in 1/2 insoluble problem situation than in 1/3 and 1/6 insoluble situations. Subjects which developed response-fixation in 1/2 insoluble situation continued to show the position response longer in test stage than others. (Table 1. & 2.) 7. 2. 2. Second Experiment : Subjects showing discriminative response entered insoluble problem. (Fig. 2.) More subjects developed position response in 2/3 and 5/6 insoluble situations than in the 1/2 situation and they established this response in fewer trials than others. In the next stage of test subjects which fixated response in 2/3 and 5/6 situations continued to show longer response than those in 1/2 situation. (Table 3, 4, 5, 6, 7, 8.) 7. 2. 3. Third Experiment : As the total number of trials in the insoluble situation was the same in each subject in the second experiment, the residual number of the trials after the establishment of position response became different in each subject. Then in this experiment the total number of trials was not the same, but that of the trials after the establishment of position response was the same. However, the result did not differ from that of the second experiment. (Table 9, 10.) 7. 3. Conclusion. 7. 3. 1. When subjects showing both random response and discriminative response entered the insoluble problems, the greater number of inconsistent trials were included in each insoluble problem, the more subjects established position response and the more promptly they established fixated response. (1/6 : 1/3 : 1/2, 1/2 : 2/3 : 5/6) In test stage the greater numbers of inconsistent trials were used in the insoluble problem, the more stronger were response fixations. (1/2 : 2/3 : 5/6). 7. 3. 2. The latency in each subject does not differ from that in the ordinary learning. (Fig. 3. & 4.)
The present study on the instrumental conditioning of color discrimination by pigeons was undertaken to determine whether the learning was based on absolute or on relative discrimination. It was assumed that if the learning was based upon relative discrimination, the luminance relation of the stimuli would be transferred regardless of their wave-length and, on the other hand, if it was based upon absolute discrimination, pigeons would respond to wave-lengths without regards to luminance relations. The entire experiment was divided into two major parts, Exp. I and II, each of which comprised two groups of experiments, A1 and B1 in the case of Exp. I and A2 and B2 in the casg of Exp. II. Each group was subdivided further into four unit-experiments, 1, 2, 3 and 4. Thus, the total number of unit-experiments was 16. The experiment was conducted with the Skinner Box and with 32 pigeons as subjects, 2 pigeons participating in one unit-experiment. Each unit-experiment contained 3 problems, 1st, 2nd and 3rd, given in this order. The purpose was to see if each succeding problem was learned more rapidly than the one preceding. Stimuli and Procedure-Four colors, red, yellow, green and blue whose dominant wave-lengths were 675.6, 574.9, 538.6 466.5mμ respectively were chosen as stimulus materials. Each of these four colors was paired with each of the other three colors. The luminance ratio of the two colors in the pair was 6 : 1, the lighter one being the positive stimulus that was reinforced. The stimuli were presented one by one in random order, each for 12 seconds through filters. The number of reinforcements per day was 32 and the criterion of learning was set at 95 percent correct response. The general plan of experiments is summarized in Table 1 and 2. The mention must be made that in Exp. I, A1 and Exp. II, A2 the color pairs used in the 3rd problem were brighter than those used in the 1st and 2nd problems and in Exp. I, B1 and Exp. II, B2 the pairs in the 2nd problem were brighter than those used in the 1st and 3rd problems. In either case, the luminance ratio of the two colors in the pair was kept 6 : 1. Results-Errors made during 32 reinforcements in the preceding problem were compared with those made in the succeeding problems and the following facts were found : Table 1 Plan of Exp. I. Transfer of learning of the 1st problem to the 3rd problem was based upon the luminance relation of the stimuli in both Exp. I, A1 and B1. This clearly is a case of relative discrimination. In Exp. II, A2 the pigeons showed both relative discrimination of luminance and absolute discrimination of wave-length, however, in B2 they showed only absolute discrimination. Transfer of learning of the 2nd to the 3rd was based almost on absolute discrimi- Table 2 Plan of Exp. II. nation in Exp. I and relative discrimination in Exp. II. The learning of the 3rd problems in Exp. I and II was accelerated in comparison with the original learning.
Generalization of escape and avoidance responses to stimuli varying in size dimension were investigated using 65 albino rats. Major problems were as follows : (1) Changes in generalization in the process of reinforcement. (2) Changes in generalization in the process of extinction. These changes were observed through absolute generalization, relative generalization, and generalization gradient measured by a response time and the number of extinction trials. The following conclusions were derived from the results obtained from two experiments : (1) Generalization increased as a function of the number of reinforcing trials. (2) Generalization decreased as a function of the number of non-reinforcing trials. (3) All generalization gradients obtained were negatively accelerated, and they decreased as a function of stimulus differences.
This investigation was carried out for the purpose of clarifying mutual human relations of workers which seems to be the important determinant of the results in co-operative performance. For this purpose two experiments were undertaken. The first experiment was arranged to see how the different combinations of workers of different sexes influence the result of cooperative performance. The results show that the different combinations clearly influence the degree of predictability of the results co-operative performance from the results of the individual workers, including the amount of production and the degree of precision of the work done. The combination of only female workers showed their maladjustment to the new situation with their partner created by co-operation, and proved the most inefficient in productivity as compared with the other combinations. It is apparent that the only female group is apt to be influenced by factors of a social situation, and is lacking in stability. The second experiment was focussed upon the combination of only female workers and arranged to manipulate the factors that influence the social situation and to clarify the nature of the mutual relation between the two female workers. The results show that the instruction given to the workers to workers td work competitively functioned to lower to the degree of the precision of the work done. While the instruction to work co-operatively could not produce the result ordinarily to be expected in other co-operative situations. Therefore it is necessary to consider the internal relationship of the performance group in its qualitative aspect. In these experiments, those groups that proved the most efficient in productivity are the combination of two workers having a fine record of efficiency, under the instruction to work competitively, and the combination of workers of low efficiency under the instruction ‘to work co-operatively.’ The results applicable to the two experiments are summarized as follows : (1) The results of co-operative performance cannot be fully predicted from the results of individual workers. In co-operative performance, the important factor to decide its result is the human relations between the co-operative workers. (2) The result of co-operative performance is not the issue of equal participation of the two workers, but much dependent upon either of them. Accordingly, there will be a leader in co-operation. (3) The effective combination in co-operative performance can be seen in rather a heterogeneous combination, such as male and female, higher and lower in his individual efficiency, competitive and co-operative than a homogeneous one. From this standpoint, we can say that the differenciation of a group may be desirable for production of leadership. (4) The group which has high probability of prediction about the result of co-operation, is superior in both quality and quantity of performance, and the reverse is also true. This fact manifests that the group which is influenced little by the factors. of situational alternation, and can exhibit desirably individual capacity, may be the excellent co-operative performance group.