Inline XBRL是否降低投資人間短期資訊不對稱？以臺灣資料為例

Does inline XBRL reduce short-term informationasymmetry among investors? Evidence fromTaiwan

本研究探討企業在使用網頁內嵌式XBRL （iXBRL）報導財務報告之後，是否能降低投資人資訊處理成本，進而降低財報發布期間投資人間之資訊不對稱。由於臺灣企業在民國108年第一季已強制採用iXBRL，本研究利用民國108年前三季與前一年相同三季的上市櫃公司資訊，發現強制iXBRL申報後，申報期間之買賣價差降低。此外，當公司申報之PDF檔案格式財報為掃描檔而無法直接搜尋內容時，會使投資人處理公司PDF檔的財務資訊成本較高，故前述iXBRL與短期買賣價差的負向關係更為顯著。本研究亦發現當公司有較多的分析師跟隨時，代表投資人有更多其他管道獲取所需之資訊，則強制採用iXBRL與短期買賣價差的負向關係將減弱。本研究預期可提供主管機關有關政策實行的可能影響的參考。

"This paper investigates whether the adoption of inline eXtensible Business Reporting Language(inline XBRL, or iXBRL) reduces the difference in the information processing costs among investors,thus reducing information asymmetry during the filing period, which is reflected in the short-term bidaskspreads. Using Taiwan data before and after iXBRL adoption in the first quarter of 2019, we firstfind that the bid-ask spreads in the filing period are smaller after iXBRL adoption. We also find thatsuch anegative association is more pronounced for firms whose Portable Document Format (PDF)-formatted financial reports are scanned and have unsearchable content. Finally, our findings showthat such anegative association is less pronounced for firms with more analysts following them. Weexpect this study to have policy implications on the effectiveness of iXBRL."