关键词: 商誉减值及时性, 商誉减值风险, 管理层过度自信, 政策监管

Abstract: This paper tracks M&A events from the start time to the time of first impairmentGoodwill duration and impairment hazard can be divided into two parts: the reasonable part and the postponed partUsing the semiparametric characteristic of the survival analysis model，this paper alleviates the measurement problem about the reasonable part of duration and hazardThis paper empirically studies the relationship between management overconfidence and the timeliness of goodwill impairmentThe results show that the overconfident management in M&A will overestimate the M&A premium and underestimate the goodwill impairment risk in the subsequent period，thus prolonging the delay time of goodwill impairment and reducing the timeliness of goodwill impairmentThe research results of this paper make a valuable supplement to the field of goodwill impairment timeliness and provide empirical evidence for the relevant departments to improve the standards of goodwill impairment

Key words: the timeliness of goodwill impairment, goodwill impairment risk, management overconfidence, policy supervision