本研究在探討企業採用XBRL技術申報財務報告的公司，是否有較低的債務資金成本與權益資金成本。以2005至2008年美國SEC公布之自願採用XBRL申報的公司為樣本，檢驗自願採用XBRL技術申報財務報告的企業是否有較低的資金成本。此外本研究並檢驗美國2009強制上市企業採用XBRL申報財務報告後的資金成本是否較強制實施前低，使用Fortune 500大企業為樣本，檢測的年度為2008及2010年。

實證結果顯示，自願採用XBRL申報的企業有較低的債務資金成本及權益資金成本，強制採用XBRL申報後權益資金成本有顯著降低，但未降低企業的債務資金成本，推估可能原因為金融海嘯發生後，信用評等公司調降企業的信用評等，因此影響XBRL對債務資金成本的效益。

This study explores the relation between XBRL and cost of capital. I examine whether voluntary filers of financial information in XBRL format have lower cost of debt and cost of equity relative to their non-adopting peers. The samples collected from the SEC website, because SEC declares companies voluntarily using XBRL filers from 2005 to 2008. I also examine whether mandatory adoption of XBRL cause the reduction of cost of capital, using Fortune 500 enterprise as the samples. U.S. publicly-held companies are mandated to file in XBRL format since 2009.

The results of this study show that companies voluntarily using XBRL have lower cost of debt and cost of equity. Additionally, cost of equity significantly reduces after mandatory adoption of XBRL, but mandatory adoption of XBRL doesn’t decrease cost of debt. The possible reason maybe that the credit rating agency lowers overall credit rating, thus affect the effectiveness of adopting XBRL.

參考文獻
Ahmed, A.S., Billings, B.K., Harris, M.S. and Morton , R.M. (2002). The role of accounting conservatism in mitigating bondholder-shareholder conflicts over dividend policy and in reducing debt costs. The Accounting Review, 77, pp. 867-890.
Ahmed, K. a. (1999). Association between Corporate Characteristics and Disclosure Levels in Annual Reports. British Accounting Review, 31, pp. 35-61.
Amihud, Y. and H. Mendelson. (1987). Trading mechanisms and stock returns: An empirical investigation. Journal of Finance, pp. 533-553.
Anderson, Ronald C., Mansi, Satter A. and Reeb, David M. (2003). Founding Family Ownership and the Agency Cost of Debt. Journal of Financial Economics, pp. 263-285.
Anderson, Ronald C., Mansi, Stttar A. and Reeb, David M. (2004). Board Characteristic, Accounting Reporting Intergrity, and the Cost of Debt. Journal of Accounting and Economics.
Bhojraj, Sanjeev and Sengupta, Partha. (2003). Effect of Corporate Governance on Bond Ratings and Yields: The Role of Institutional Investors and Outside Directs. Journal of Business, 76(3), pp. 455-475.
Botosan, C. A. (1997, Jul). Disclosure Level and the Cost of Equity Capital. The Accounting Review, 72(3), pp. 323-349.
Botosan, C.A.; Plumlee, M. (2002). Re-Examination of isclosure Level and the Expected Cost of Equity Capital. Journal of Accounting Research, 40(1), pp. 21-40.
Chen, K. C. W., Chen Z. H. and Wei J. K. C. (2004). Disclosure, Corporate Governance, and the Cost of Equity Capital in Emerging Markets. SSRN Working Paper.
Debreceny, Roger and Gray, Glen L. (2001). The production and use of semantically rich accounting reports on the Internet: XML and XBRL. International Journal of Accounting Information Systems(2), pp. 47-74.
Dhaliwal, Dan S, Gleason, Cristi A, Heitzman, Shane and Melendrez, Kevin D. (2007). Auditor Fees and Cost of Debt. Journal of Accounting, Auditing and Finance.
Dhaliwal, Dan, Hogan, Chris and Trezevant, Robert. (2011). Imternal Control Disclosures, Monitoeing, and the Cost of Debt. The Accounting Review, 86(4), pp. 1131-1156.
Easton, P. D. (2004). PE Ratios, PEG Ratios, and Estimating the Impiled Expected Rate of Return on Equity Capital. The Accounting Review, 79(1), pp. 73-95.
El-Gazzar, S. M. (1998). Predisclosure Information and Institutional Ownership: A Cross-sectional Examination of Market Revaluations during Earnings Announcement Periods. Accounting Review(79), pp. 119-129.
Eng, L.L. and Mak, Y.T. (2003). Corporate Governence and Voluntary Disclosure. Journal of Accounting and Public Policy, 32, pp. 325-345.
Fama, E.F. and French, K.R. (1997). Industry Costs of Capital. Journal of Financial Economics, 43(2), pp. 153-193.
Francis, Jennufer, Nanda, Dhanajay and Olsson, Per. (2008, March). Voluntary Disclosure, Earings Quality, Cost of Debt. Journal of Accounting Research, 46(1), pp. 475-679.
Francis, Jere R., Khurana, Inder K. and Pereira, Raynolde. (2005). Disclosure Incentives and Effects on Cost of Capital around the World. The Accounting Review, 80(4), pp. 1125-1162.
Gray, R., Kouhy, R. and Lavers, S. (1995). Corporate social and environmental reporting: A review of the literature and a longitudinal study of UK disclosure. Accounting, Auditing and Accountability Journal, 8(2), pp. 47-77.
Hail, L. (2002). The Impact of Voluntary Corporate Disclosure on the Ex-ante Cost of Capital for Swiss Firms. The European Accounting Review, 11(4), pp. 741-773.
Healy, P.M., Hutton, A.P. and Palepu, K.G. (1999). Stock Performance and Intermediation Changes Surrounding Sustained Increases in Disclosure. Contemporary Accounting Research, 3, pp. 485-520.
Healy, Paul M. and Palepu, Krishna G. (2001). Information asymmetry, corporate disclosure, and the capital markets: A review of the empirical disclosure literature. Journal of Accounting and Economics, 31, pp. 405-440.
Hodge, Frank D., Kennedy, Jane Jollineau and Maines, Laureen A. (2004). Does Search-Facilitating Technology Imporve the Transparency of Financial Reporting? The Accounting Review, 79(3), pp. 687-703.
Jiang, J. (2008). Beating Earnings Benchmarks and the Cost of Debt. THE ACCOUNTING REVIEW, 83(2), pp. 377-416.
Lang, Mark and Lundholm, Russell. (1993). Cross-Sectional Determinants of Analyst Ratings of Corporate Disclosures. Journal of Accounting Research, 31(2), 頁 246-271.
Leuz, C. and Verrecchia, R.E. (2000). The Economic Consequences of Increased Disclosure. Journal of Accounting Research, 38(1), 頁 91-124.
Michael C. Jensen, William H. Meckling. (1976). Theory of the firm: managerial behavior, agency costs and ownership structure. Journal of Financial Economics, 3(4), pp. 305-360.
Ohlson, James A. and Juettner-Nauroth, Beate E. (2005). Expected EPS and EPS Growth as Determinants of Value. Review of Accounting Studies, pp. 349-365.
Premuroso, Ronald F. and Bhattacharya, Somnath. (2008). Do early and voluntary filers of financial information in XBRL format signal superior corporate governance and operating performance? International Journal of Accounting Information Systems, 9(1), pp. 1-20.
Sengupta, P. (1998). Corporate Disclosure Quality and the Cost of Debt. The Accounting Review, pp. 459-474.
Welker, M. (1995). Disclosure Policy, Information Asymmetry and Liquidity in Equity Markets. Contemporary Accounting Research, 11(2), pp. 801-827.
Yoon, Hyungwook, Zo, Hangu and Ciganek, Andrew P. (2011). Does XBRL Adoption Reduce Informtion Asymmetry? Journal of Business Research, pp. 157-163.
周濟群. (2009). 利用XBRL技術設計可剖析的開放式企業報告架構. 東吳會計學報, 1(2), 頁 1-35.