In this study, a hoarding tendency is defined as a trait whereby many possessions are saved and cannot be discarded because of their subjective meaning. For this study, an internet-survey of non-clinical individuals was conducted. First, the effects of age and gender on expression of hoarding were investigated. Next, as the main purpose of this study, the causal relationships between hoarding tendencies and various problems that hoarding causes were investigated. Four hundred and fifty-three participants were asked to complete a questionnaire. The main findings were as follows: 1) Females and people in their 30s significantly tended to hoard possessions. 2) The results of analysis indicated that hoarding caused mental problems, economic problems, social problems, and functional problems. In addition, a covariance structure analysis for the proposed model suggested that excessive attachment to possessions, such as “avoidance of discarding possessions” and “extended self,” caused an excessive build-up of items in the home, and these functional problems resulted in the above-mentioned problems. 3) Furthermore, the results of multi-sample simultaneous analysis indicated that the causal model for participants in their 60s was greatly different from that of other age groups. That model revealed that people in their 60s did not hesitate to throw belongings away and did not have the various problems that hoarding causes.

This study examined trust in artificial intelligence in medical care and identified its determinants. Studies on risk perception have found that perceived ability, integrity, and value similarity determine trust in risk managers. Further, engineering studies on trust in artificial intelligence have suggested that perceived ability and integrity determine trust. However, few researchers have examined whether perceived value similarity affects trust in artificial intelligence. We employed a situation assumption method and focused on the shared policy of medical treatment. In Study 1 (n＝165), the results revealed that the shared policy of medical treatment enhanced participants’ trust in artificial intelligence, as it did in humans. In addition, artificial intelligence was less trusted than humans were. Study 2 (n＝139) replicated the experiment conducted in Study 1 by improving items for manipulation check. The results of Study 2 mostly reproduced those of Study 1. Empirical implications of the findings are discussed.

The present study aims to investigate when and why helping behaviors are criticized by a third party. We propose that people infer an ulterior selfish motive for others’ helping behaviors that occur in some self-presentational contexts. A vignette study was conducted with 149 undergraduates who read scenarios describing helping behaviors in various kinds of contexts. Analysis using a multi-level structural equation model provided partial support for our notion. It was shown that selfish motives were more likely inferred in situations in which observers who happened to be there praised the helping behavior than otherwise. However, this did not lead to increased criticism. It was also shown that the help was more likely regarded as needless, and, therefore, selfish motives were more strongly inferred when the help was refused than when it was requested by a recipient. Some methodological problems and future directions are discussed.

This study attempted to investigate the differences in tourists’ perceptions of destination images based on their past travel experiences. Tourism research suggests that past travel experiences affect present tourist behavior in terms of travel career and number of visits. In this study, we consider the tourist as a person seeking mastery through travel experiences and use measures of guest experience from 47 prefectures in Japan. Five hundred respondents living in Osaka were asked to complete a questionnaire via the Internet. Respondents had to identify 10 destination images and write about their travel experiences in as many of the 47 prefectures as they had visited. The main results were as follows: (1) respondents were classified into four clusters according to their travel experiences, (2) tourists who had traveled to more prefectures had an image of the destination based on geographical location and destination characteristics, and (3) tourists who had previously visited a particular destination and had been to more prefectures had a clear image of the destination. Based on these results, the process through which tourists develop expertise was discussed.

Due to the diffusion of the internet and the increase in the number of politicians who attack mass media and gain support, the problem of a decrease in the public’s trust in mass media is gaining attention both in Japan and abroad. However, the wording of questions measuring trust in mass media (TVs, newspapers, and magazines) is not consistent; hence it is difficult to examine whether trust is declining or not. We reviewed the previous findings of representative social surveys and revealed three differences in question wording: (1) degree adverbs assigned to choices of 4-point scales, (2) whether to measure trust in newspapers and magazines together, (3) whether to clearly indicate that the target of the question is an organization. We conducted a randomized web survey experiment to explore the differences in expressed trust based on question wording. As a result, level of the trust in media differs by up to 25％ or more depending on the question wording. The findings indicate the importance of choosing question wording with a clear reason in measuring trust in media.