A Pilot Study Using AI for Psychology: ABO Blood Type and Personality Traits
AI predicted the blood type of participants more accurately than chance. We found a clear relationship between blood type and the self-reported personality of many question items, which matches traits previously stated. The same traits were observed in the no-knowledge groups, though the difference was smaller. Our findings provide a new, if hypothetical, framework of how genes affect human personality. Meanwhile, the sample in this study was limited to Japanese populations only, the AI training data was small in sample size, and its use experimental. Additional research using a larger, global dataset is needed in order to address true implications, as well as to improve algorithms and methodologies.
Preceding research by psychologists had concluded that there appeared no difference in personality among blood types, and that even if there was a difference predicted by the blood type, it was assumed to be the result of self-fulfillment prophecy phenomena [14,17-19,20,23,25-26]. However, the same differences in scores were found in the “no-knowledge” groups, although the values were smaller. Therefore, it is highly likely that differences by blood type are real, not caused by self-fulfilling prophecy phenomena; no difference in the “no-knowledge” groups were caused by Type II errors. In addition, backed on this study’s AI result, it was suggested that these phenomena occurred not only because of the wording of question items, but also because gender and age were not taken into account. Our experimental blood type predictions by AI (Amazon Machine Learning) in this study found that adding non-blood type variables, such as gender or age, to the training data considerably increased the accuracy (Tables 4 and 5). Moreover, when performing blood type prediction, AI sometimes failed to build its machine learning models, if gender or age of the training and prediction data were different. In this respect, AI technology may suggest that factors such as gender and age affect the traits of blood type. Therefore, gender, age, and other factors may offer a better explanation, even if past data were inconsistent. The issue concerning the difference of human personality affected by gender and age, have been explored in the fields of personality psychology and social psychology. Although some people argue that personalities are affected by gender and age, and the differences are non-linear [40-41], others argue that they are not affected [42]. In any case, many researchers seem to agree upon the existence of differences, at least self-reported. We also believe that there are such differences. Our study has several points to be improved. Firstly, the participants in this study were limited to Japanese populations only. It is necessary to examine whether the same results can be obtained in samples of other countries. Secondly, we used the 2,000- and 4,000-population AI training data, but these are relatively small sample sizes; 10,000 or more persons are desirable. Lastly, researchers have not yet found an appropriate method to utilize AI for personality psychology.