Fitting a psychometric function to price judgments: an analysis of consumers' discounted prices

We examined a psychometric function of price judgment, comparing the mental ruler model, which predicted inverted S-shaped psychometric function, with a power function. Subjects, 102 citizens living in Japan, were asked to rate satisfaction with specified discounted prices. Analysis indicated that predictions of the mental ruler model gave a better fit than those of the power function.     

Is g an entity? A Japanese twin study using syllogisms and intelligence tests

Using a behavioral genetic approach, we examined the validity of the hypothesis concerning the singularity of human general intelligence, the g theory, by analyzing data from two tests: the first consisted of 100 syllogism problems and the second a full-scale intelligence test. The participants were 448 Japanese young adult twins (167 pairs of identical and 53 pairs of fraternal twins). Data were analyzed for their fit to two kinds of multivariate genetic models: a common pathway model, in which a higher-order latent variable, g, was postulated as an entity; and an independent pathway model, in which the higher-order latent variable was not posited. These analyses revealed that the common pathway model which included additive genetic and nonshared environmental factors best accounted for the three distinct mental abilities: syllogistic logical deductive reasoning, verbal, and spatial. Both the substantial g-loading for syllogism-solving, historically recognized as the symbol of human intelligence, and the emergence of g as an entity at an etiological level, that is, at the genetic and environmental factor level, provide further support for the g theory.     

Perceptions of the Concept of Mutation among Family Members of Patients Receiving Outpatient Genetic Services and University Students

Our objectives were to investigate: (1) relationships between perceptions of various terms regarding mutation and the depth of knowledge regarding mutation among family members of patients receiving genetic outpatient services, and (2) differences in perceptions of the term “gene mutation” for family members versus university students. Fifty-eight family members and 178 university students responded to two questionnaires: Impressions regarding the term, and Knowledge about the concept of mutation. Factor analyses were conducted to determine the factor structure of ratings of the terms, and two-way analyses of variance [(1)Term, (2)Group × Knowledge] were conducted to examine differences in perceptions of the terms as measured by scores for each extracted factor. Family members had a significantly more negative perception of the term “gene mutation” than “gene change” and a less negative perception of the term “gene mutation” than “gene lesion”; they had significantly more negative perceptions of the term “gene mutation” than did university students.     

Are Japanese groups more competitive than Japanese individuals? A cross‐cultural validation of the interindividual–intergroup discontinuity effect

The interindividual–intergroup discontinuity effect is the tendency for relationships between groups to be more competitive than the relationships between individuals. It has been observed robustly in studies conducted in the United States, which is a society characterized as “individualistic.” In this study, it was explored whether the effect was replicable in a “collectivistic” society such as Japan. From the traditional view in cross‐cultural psychology, which emphasizes the collectivistic nature of East Asian peoples, it was expected that the discontinuity effect would be greater in Japan than in the United States. On the other hand, based on recent empirical findings suggesting that North Americans are no less group‐oriented than East Asians, it was expected that the discontinuity effect would be no greater in Japan than in the United States. One hundred and sixty Japanese university students played a 10‐trial repeated prisoner's dilemma game: 26 sessions of interindividual and 18 sessions of intergroup. Following exactly the procedure of prior experiments in the US, individuals and groups were allowed face‐to‐face communication with their opponents before making their decisions, and participants in the intergroup condition were further allowed to converse freely with their in‐group members. Results replicated previous findings in the United States; groups made more competitive choices than did individuals. In addition, neither the magnitude of the discontinuity effect, nor the frequency of competitive choices made by the groups, were larger in Japan than they were in the majority of prior studies conducted in the United States. These findings suggest cross‐cultural robustness of the interindividual–intergroup discontinuity effect. Also, interestingly, they contradict the simple distinction between individualism and collectivism. Implications for studies of culture and group processes are discussed.     

Attending inside or outside: A Japanese–US comparison of spontaneous memory of group information

A recent review of empirical evidence disconfirmed the widely‐held view that North Americans are less collectivistic than East Asians. However, previous research has proposed that the motivations underlying group behaviours differ across cultures: North Americans are more strongly motivated to acquire and maintain higher in‐group status relative to outgroups, whereas East Asians tend to emphasize maintenance of reciprocal relationships within in‐groups. We tested this hypothesis by examining the pattern of attentional allocation in group situations using a memory task. As predicted, compared to Japanese, memory performance among Americans was biased towards intergroup status difference over intragroup relationship information.     

Similarity attraction and actually selecting similar others: How cross-societal differences in relational mobility affect interpersonal similarity in Japan and the USA

Several studies have demonstrated that similarity between friendship partners is higher in the West than in East Asian countries. We hypothesized that these differences could be explained by relational mobility, or the number of opportunities to form new relationships in a given society. Through two studies, we confirmed that whereas the preference for similarity did not differ, similarity between friendship partners was higher in the USA than in Japan. Furthermore, a measure of relational mobility mediated the cultural difference in similarity, supporting our hypothesis. The effectiveness of considering socio-ecological factors when interpreting cultural differences in behaviour is discussed.     

Voluntary settlement and the spirit of independence: evidence from Japan's "Northern frontier"

The authors hypothesized that economically motivated voluntary settlement in the frontier fosters independent agency. While illuminating the historical origin of American individualism, this hypothesis can be most powerfully tested in a region that is embedded in a broader culture of interdependence and yet has undergone a recent history of such settlement. The authors therefore examined residents of Japan's northern island (Hokkaido). Hokkaido was extensively settled by ethnic Japanese beginning in the 1870s and for several decades thereafter. Many of the current residents of Hokkaido are the descendents of the original settlers from this period. As predicted, Japanese socialized and/or immersed in Hokkaido were nearly as likely as European Americans in North America to associate happiness with personal achievement (Study 1), to show a personal dissonance effect wherein self-justification is motivated by a threat to personal self-images (Study 2), and to commit a dispositional bias in causal attribution (Study 3). In contrast, these marker effects of independent agency were largely absent for non-Hokkaido residents in Japan. Implications for theories of cultural change and persistence are discussed.     

A Generalized Syllogistic Inference System based on Inclusion and Exclusion Relations

We introduce a simple inference system based on two primitive relations between terms, namely, inclusion and exclusion relations. We present a normalization theorem, and then provide a characterization of the structure of normal proofs. Based on this, inferences in a syllogistic fragment of natural language are reconstructed within our system. We also show that our system can be embedded into a fragment of propositional minimal logic.     

The influence of decision heuristics and overconfidence on multiattribute choice: A process-tracing study

In the present study it was shown that decision heuristics and confidence judgements play important roles in the building of preferences. Based on a dual-process account of thinking, the study compared people who did well versus poorly on a series of decision heuristics and overconfidence judgement tasks. The two groups were found to differ with regard to their information search behaviour in introduced multiattribute choice tasks. High performers on the judgemental tasks were less influenced in their decision processes by numerical information format (probabilities vs. frequencies) compared to low performers. They also looked at more attributes and spent more time on the multiattribute choice tasks. The results reveal that performance on decision heuristics and overconfidence tasks has a bearing both on heuristic and analytic processes in multiattribute decision making.     

Proof Theory for Reasoning with Euler Diagrams: A Logic Translation and Normalization

Proof-theoretical notions and techniques, developed on the basis of sentential/symbolic representations of formal proofs, are applied to Euler diagrams. A translation of an Euler diagrammatic system into a natural deduction system is given, and the soundness and faithfulness of the translation are proved. Some consequences of the translation are discussed in view of the notion of free ride, which is mainly discussed in the literature of cognitive science as an account of inferential efficacy of diagrams. The translation enables us to formalize and analyze free ride in terms of proof theory. The notion of normal form of Euler diagrammatic proofs is investigated, and a normalization theorem is proved. Some consequences of the theorem are further discussed: in particular, an analysis of the structure of normal diagrammatic proofs; a diagrammatic counterpart of the usual subformula property; and a characterization of diagrammatic proofs compared with natural deduction proofs.