日本・オランダ・コスタリカ3か国におけるさまざまな幸福感と楽観性・悲観性との関連性

抄録

This study reports the international comparison of the relationship between a variety of questions pertaining to happiness and optimism/pessimism. The revised Life Orientation Test scores of 100 Japanese, 45 Dutch, and 100 Costa Ricans were statistically analyzed. The respondents’ happiness level was assessed using five single-item questions regarding present happiness, ideal happiness, present life satisfaction, Cantril’s Ladder of Life Scale, and predicted happiness five years later. The results indicated that the more optimistic the participants were, the happier or more positive they felt about their life, regardless of their nationality. We also found a significant country × pessimism interaction on ideal happiness, such that the ideal happiness of pessimistic Japanese people was lower than that of non-pessimistic Japanese people. Moreover, higher optimism scores predicted higher life satisfaction in Japanese than Dutch or Costa Rican respondents. The results also indicated that optimistic and non-pessimistic Japanese tended to have higher expectations about their future happiness. These findings suggest that the relationship between happiness and optimism/pessimism depends on nationality and the type of question regarding happiness.