法人說明會對企業資訊不對稱的影響

The Effect of Conference Calls on Information Asymmetry

由於法人說明會是台灣上市櫃企業重要的自願性揭露工具，本文檢視企業召開法人說明會對其資訊不對稱之影響。在以日資料的優勢資訊交易機率(Probability of information-based trading)補捉資訊不對稱的前提下，使用傾向分數配對法(propensity score matching)並搭配差異中差異估計法(difference-in-differences)，本文發現法人說明會得以降低企業資訊不對稱的程度。再者，本文亦採召開法人說明會前一日的優勢資訊交易機率進行配對及採Heckman 兩階段迴歸模型進行敏感性檢測，亦再次驗證本研究的發現。這些證據進一步表示企業的自願性揭露可以減緩資本市場中資訊不對稱的問題。

This study uses an examination of the intra-day probability of information-based trading to determine whether holding conference calls can reduce the degree of information asymmetry. This study adopts propensity score matching and difference-in-differences estimation method. Furthermore, we also use pre-day probability of information-based trading to implement matching and Heckman two-stage model for a sensitivity analysis. Our results support the hypothesis, and thus provide evidence that such voluntary disclosures can mitigate information asymmetry problem in the capital market of Taiwan.