Abstract: Over the last 2 decades, a substantial body of research has uncovered the impact bias, which reflect the tendency for people to overestimate the initial impact and/or duration of emotional event (Gilbert, Pinel, Wilson, Blumberg, & Wheatley, 1998；Wilson, Wheatley, Meyers, Gilbert, & Axsom, 2000；Levine, Lench, Kaplan, & Safer, 2012；Wirtz, Kruger, Scollon, & Diener, 2003) . Why do we persistently make these errors in our affective forecasts? One proposal is focalism, the other is unforeseen adaptation. However, the boundary conditions of focalism and unforeseen adaptation remain poorly understood. When is the focalism more important for the impact bias? To answer these questions, two experiments were conducted. With between-subject design in experiment 1 and within-subject design in experiment 2, participants were first asked to predict the affect after different events (being admitted to graduate in E1a, taking facture surgery in E1b, moving to new campus in E2), then experienced the events. All participants were randomly assigned to one of three conditions, that is, defocusing exercise, adaptation exercise, and control condition. The effects of three conditions on impact bias were compared. In experiment 1, the affect prediction and experience were compared by t - test, results showed that under the condition of defocusing exercise there is no significant difference between affect prediction and experience（E1a: t=0.94，p>0.05; E1b: t=1.67，p>0.05）, which means there was no impact bias. However, under the condition of adaptation exercise (E1a: t=2.24，p<0.05; E1b: t=2.82，p<0.01) and control condition（E1a: t=2.50, p<0.05; E1b: t=3.11，p<0.01）, the affect was overestimated, which means there was impact bias. In experiment 2, first in the participant level, the affect experience was regressed on affect prediction over six time point, in which the regression coefficient βreflected the accuracy of affect prediction. Then, the regression coefficients of three conditions (defocus exercise, adaption exercise, and control condition) were compared by ANOVA. Results showed that the defocusing exercise improved accuracy of affective forecast significantly, however, both adaptation exercise and control condition overestimate the effect of future events（F(2,151) =2.99，p<0.05）. Therefore, in the present study, the focalism is the main source of impact bias. Because the affective tasks of the present study provided clear situational clue, it concluded that when the situational clue is clear, focalism is the main source of impact bias. The present study has important theoretical contribution in that it clarified the boundary condition of focalism and unforeseen adaptation in the impact bias from the viewpoint of information using. The present study is also very important to reduce the impact bias, for example, when the situational clue is clear, the impact bias can be reduced significantly by defocusing exercise.

Key words: affective forecasting, impact bias, focalism, unforeseen adaptation, information using

摘要： 为了考察情感预测影响偏差中聚焦错觉和适应忽视的作用，本研究通过两个实验，先让大学生被试对考研（实验1a）、骨折手术（实验1b）、搬到新校区（实验2）进行情感预测，然后将其与情感体验进行比较，并比较了去焦点化训练、适应训练和控制组对影响偏差的干预效果。结果发现：去焦点化训练显著地降低了情感预测的影响偏差，而适应训练和控制组则没有显著降低影响偏差。因此，本研究认为，当情境线索清楚的时候，聚焦错觉是导致情感预测影响偏差的主要原因。

关键词: 情感预测, 影响偏差, 聚焦错觉, 适应忽视, 信息利用