年報中語調之改變對市場與未來績效之影響

Abstract

本研究旨在探討年報中之內容是否具有資訊內涵。研究使用內容分析法將年報中之文字，分為正面詞與負面詞兩類，以衡量管理階層負面語調之改變。研究結果顯示，在年報公告日附近，負面語調之改變增加(減少)，對短期的市場反應有顯著反面(正面)之影響。負面語調之改變對長期之市場反應亦有顯著負向關係。研究亦發現，負面語調之改變增加(減少)，可預測公司未來績效較差(較佳)，顯示語調之改變具有預測能力。對資訊環境的測試結果，顯示負面語調之改變所含的資訊內涵，受分析師預測報告多寡影響。

This study explores whether the annual report has incremental information content. It uses content analysis to classify words into positive and negative sentiment to measure the negative tone change in annual report relative to prior filing. Its results indicate that when the negative tone change increases (decreases), the short window market reactions around the releasing of annual report would significantly decrease (increase). The drift returns are also significantly negatively related to the negative tone change. This study also finds the negative tone change could predict firm’s future performance. The increase (decrease) of negative tone change could predict worse (better) future performance. In the test of information environment, the incremental information of management’s negative tone change depends on the number of analyst forecasts.