過去文獻顯示，損益平穩化擁有正反兩面競爭性意涵。由溝通私有資訊來看，管理當局透過會計裁量權傳達對未來盈餘之展望，則損益平穩化有助於增進企業盈餘資訊內涵。反之，若由自利行為動機來看，管理當局進行損益平穩化乃是為了操弄盈餘，則企業盈餘品質將受損害。綜上所述，損益平穩化具有「增進」或「扭曲」盈餘資訊的效果，而究竟何種效果較具優勢，有待實證的探討。

本文檢視企業策略性調控遞延所得稅資產備抵評價(簡稱DTA備抵評價)行為，探究該行為究竟是遵守會計準則規範，亦或出於盈餘管理動機。若管理當局基於會計準則規範調控DTA備抵評價金額，以反應遞延所得稅資產(簡稱 DTA)正負面證據，則DTA金額不僅更具合理性，亦有助於增進盈餘資訊效果。另一方面，若管理當局將DTA備抵評價視為盈餘管理工具，操弄盈餘以滿足私利，則損及盈餘資訊效果。是故，本文解構DTA備抵評價組成因子，由裁量性因子檢視企業策略性調控DTA備抵評價行為之本質。

本文實證結果發現：（1）在其他條件不變情況下，企業遵照會計準則規範策略性調控DTA備抵評價金額，修正會計盈餘水準；（2）在其他條件不變情況下，對於沖銷資產企業而言，管理當局調控DTA備抵評價金額乃是反應DTA正負面證據，以遵守會計準則規範；（3）在其他條件不變情況下，對於未沖銷資產企業而言，可能存有少數企業基於盈餘管理需求調控DTA金額，以平穩化稅後盈餘。

Prior research indicates that income smoothing has positive/negative competing implications. Under communicating private information perspectives, income smoothing effectively improves earnings informativeness if managers use their accounting discretion to communicate their assessment of future earnings. Under self-interest motivation perspectives, income smoothing makes earnings noisier and drops earnings informativeness when managers distort the earnings numbers. Two key concepts suggest that income smoothing has improving-versus-garbling debate. Which effect dominates in a cross-sectional setting is an open question to verify.

The main purpose of this paper is to analyze the discretionary decision on valuation allowance of deferred tax assets (DTA hereafter) whether it’s earnings management or not. According to accounting standards setting, managers establish valuation allowance to adjust DTA after evaluating the evidence of DTA realization. On the contrary, managers manipulate income while considering valuation allowance of DTA as an earnings management tool. After controlling the non-discretionary part of valuation allowance, the empirical results show the nature of discretionary decision on valuation allowance of DTA.

In same circumstance, empirical results indicate that (1) There is a significant negative relation between discretionary valuation allowance and changes in earnings before income tax. (2) In non-cash charge firms, the discretionary decision on valuation allowance stemmed from accounting standards. (3) We do not find any evidence that reversals of valuation allowances are used to distort earnings in without non-cash charge firms. However, we do find a very small number of firms that seem to have used a valuation allowance reversal to meet the analyst forecast.

一、中文文獻
吳清在與林松宏，2003，遞延所得稅資產備抵評價之決定因素及價值攸關性：台灣上市公司之實證研究，中華會計學刊，第3卷第2期（4月）：201-236。
林松宏，2004，遞延所得稅評價之研究，國立成功大學會計學研究所博士論文。
林娟慧，2005，遞延所得稅資產備抵評價之資訊內涵及股價資訊性：台灣上市公司之實證研究，國立成功大學會計學研究所碩士論文。
林嬌能，2006，帳面-課稅所得差異與盈餘管理之相關性，國立成功大學會計學研究所博士論文。
財團法人中華民國會計研究發展基金會，1994，財務會計準則公報第二十二號：所得稅之會計處理準則。
財團法人中華民國會計研究發展基金會，1999，財務會計準則公報第二十二號：所得稅之會計處理準則，最新修訂版。
徐景亮，1992，美國新所得稅會計處理準則（上），會計研究月刊，第八十七期，頁107-115。
徐景亮，1992，美國新所得稅會計處理準則（中），會計研究月刊，第八十八期，頁51-88。
徐景亮，1992，美國新所得稅會計處理準則（下），會計研究月刊，第八十九期，頁146-152。
張仲岳與梁鈺涓，2001，所得稅暨退休金會計準則公報攸關性資訊品質之探討，會計評論，第33期：27-55。
張至誼，2001，遞延所得稅資產評價之盈餘管理探討，國立台灣大學會計學研究所碩士論文。
張敏蕾與黃德芬，2007，遞延所得稅費用策略性調控與公司盈餘管理行為，當代會計，第8卷第2期（11月）：181-208。
張慧珊，2002，兩稅合一制度對於股權評價之影響研究，國立台灣大學會計學研究所碩士論文。
陳依依，1998，遞延所得稅資產評價之實證研究，國立中正大學會計學研究所碩士論文。
陳佳真，2007，遞延所得稅資產備抵評價盈餘平穩化之研究，國立成功大學會計學研究所碩士論文。
陳明進，2002，營利事業有效稅率決定因素之實證研究，會計評論，第34期：57-75。
陳明進，2003，我國租稅優惠對營利事業租稅負擔之影響，管理評論，第22卷第1期：127-151。
蘇淑美，1997，所得稅公報對市場效應之研究，國立台灣大學會計學研究所碩士論文。

二、英文文獻
Alford, A., J. Jones, R. Leftwich, and M. Zmijewski. 1993. The relative informativeness of accounting disclosures in different countries. Journal of Accounting Research 31 (Supplement): 183-223.
Amir, E., M. Kirschenheiter, and K. Willard. 1997. The valuation of deferred taxes. Contemporary Accounting Research 14 (Winter): 597-622.
Amir, E., and T. Sougiannis. 1999. Analysts’ interpretation and investors’ valuation of tax carry forwards. Contemporary Accounting Research 16 (1): 1-33.
Badertscher, B., J. Phillips, M. Pincus, and S. Rego. 2009. Earnings management strategies: To conform or not to conform? The Accounting Review 84 (2): 63–98.
Barth, M., and G. Clinch. 1996. International accounting differences and their relation to share prices: Evidence from U.K., Australian and Canadian Firms. Contemporary Accounting Research 13: 135-170.
Bartov, E. 1993. The timing of asset sales and earnings manipulations. The Accounting Review 50 (January): 840-855.
Bartov, E., F. A. Gul, and J. Tsui. 2000. Discretionary-accruals models and audit qualifications. Journal of Accounting and Economics 30: 421-452.
Bauman, C. C. 1997. Accounting choice and valuation consideration of SFAS No. 109. Working paper, Unpublished Ph. D. Dissertation. University of Wisconsin-Madison.
Bauman, C. C., and M. P. Bauman. 2000. The deferred tax asset valuation allowance as a strategic accounting choice. Working paper, University of Wisconsin-Milwaukee , and University of Illinois-Chicago.
Bauman, C. C., M. P. Bauman, and R. F. Halsey. 2001. Do firms use the deferred tax asset valuation allowance to manage earnings? The Journal of the American Taxation Association 23 (Spring): 27-48.
Beatty, A. L., B. Ke, and K. R. Petroni. 2002. Earnings management to avoid earnings declines across publicly and privately held banks. The Accounting Review 77 (3): 547-570.
Beaver. W. H. 2002. Perspectives on recent capital market research. The Accounting Review 77: 453-474.
Behn, B. K., T. V. Eaton, and J. R. Williams. 1998. The determinants of the deferred tax allowance account Under SFAS No. 109. Accounting Horizons (March): 63-78.
Beidleman, C. R. 1973. Income smoothing: The role of management. The Accounting Review 48 (October): 653-667.
Bernard, V., and D. Skinner. 1996. What motivates managers’ choice of discretionary accruals? Journal of Accounting and Economics 22 (1-3): 313-325.
Boynton, C., P. DeFilippes, and E. Legel. 2005. Prelude to Schedule M-3: Schedule M-1 corporate book-tax difference data 1990–2003. Proceedings of the Annual Conference on Taxation, 131–137. Washington, D.C.: National Tax Association–Tax Institute of America.
Burgstahler, D. and I. Dichev. 1997. Earnings management to avoid earnings decrease and losses. Journal of Accounting and Economics 24 (1): 99-126.
Burgstahler, D., W. B. Elliott, and M. Hanlon. 2002. How firms avoid losses: Evidence of use of the net deferred tax asset account. Working paper, University of Washington.
Chao, C. L., R. L. Kelsey, S. M. Horng, and C. Y. Chiu. 2004. Evidence of earnings management from the measurement of the deferred tax allocation account. The Engineering Economist 49 (1)：63-93.
Chen, K. 1991. “The timing of asset write downs in the oil and gas industry: 1985-1986”. Petroleum Accounting and Financial Management Journal (Fall/Winter): 157-169.
Chen, K. C., and B. K. Church. 1992. Default on debt obligations and the issuance of going-concern opinions. Auditing: A Journal of Practice & Theory (Fall): 30-49.
Christensen, T. E., G. H. Park, and E. K. Stice. 2008. Creating a bigger bath using the deferred tax valuation allowance. Journal of Business Finance and Accounting 35 (5) & (6): 601-625.
Collins, J. D., and P. Hirbar. 2000. Errors in estimating accruals: Implications for empirical research. Working paper, University of Iowa.
DeAngelo, L. 1986. Accounting numbers as market value substitutes: A study of Managerial buyouts of public stockholders. The Accounting Review 61 (3): 400-420.
DeAngelo, L. 1988. Managerial competition, information costs, and corporate governance: The use of accounting performance measures in proxy contests. Journal of Accounting and Economics 10: 3-36.
Dechow, P., and R. G. Sloan. 1991. Executive incentives and the horizon problem: An empirical investigation. Journal of Accounting and Economics 14: 51-89.
Dechow, P. 1994. Accounting earnings and cash flows as measures of firm performance: The role of accounting accruals. Journal of Accounting and Economics 17 (January): 3-42.
Dechow, P., R. G. Sloan, and A. Sweeney. 1995. Detecting earnings management. The Accounting Review 70 (2): 193-225.
DeFond, M., and K. R. Subramanyam. 1998. Auditor changes and discretionary accruals. Journal of Accounting and Economics 25: 35-67.
DeGeorge, F., J. Patel, and R. Zeckhauder. 1999. Earnings management to exceed thresholds. Journal of Business 72 (1): 1-33.
Desai, M. 2002. International taxation and multinational activity. National Tax Journal 55: 845–848.
Desai, M. 2005. The degradation of reported corporate profits, Working paper, NBER, Harvard Business School.
Dhaliwal, D., C. A. Gleason, and L. F. Mills. 2004. Last chance earnings management: Using the tax expense to meet analysts’ forecasts. Contemporary Accounting Research 21 (Summer): 85-112.
Dhaliwal, D., R. Huber, H., S. Lee, and M. Pincus. 2008. Variability of book-tax differences, information uncertainty, and implied cost of capital. Working paper. The University of Arizona and University of California, Irvine.
Eighme, J. E. 2001. The valuation allowance for deferred tax assets and earnings management, Working paper, The Florida State University.
Elliott, J., and W. Shaw. 1988. Write-offs as accounting procedures to manage perceptions. Journal of Accounting Research 26 (Supplement): 91-119.
Financial Accounting Standards Board. 1992. Statement of Financial Accounting Standards No. 109: Accounting for Income Taxes.
Francis, J., J. Hanna, and L. Vincent. 1996. Causes and effects of discretionary asset write-offs. Journal of Accounting Research 34 (Supplement): 117-134.
Frank, M. M., and S. O. Rego. 2006. Do managers use the valuation allowance account to manage earnings around certain earnings targets? The Journal of American Taxation Association 28(1): 43-65.
Frank, M. M., J. Lynch, and S. O. Rego. 2009. Tax Reporting Aggressiveness and Its Relation to Aggressive Financial Reporting. The Accounting Review 84(2): 467-496.
Gordon, E. A., and P. R. Joos. 2004. Unrecognized deferred taxes: Evidence from the UK. The Accounting Review (Jan): 97-124.
Guay, W., S. P. Kothari, and R. Watts. 1996. A market-based evaluation of discretionary accrual models. Journal of Accounting Research 34 (Supplement): 83-105.
Gujarrathi, M. R., and R. E. Hoskin. 1992. Evidence of earnings management by the early adoption of SFAS No.96. Accounting Horizons (4): 18-31.
Hagerman, R., and M. Zmijewski. 1981. An income strategy approach to the positive theory of accounting standard setting/choice. Journal of Accounting and Economics (August): 129-149.
Hand, J. 1989. Did firms undertake debt-equity swaps for an accounting paper profit or true financial gain? The Accounting Review (October): 587-623.
Hanlon, M. 2005. The persistence and pricing of earnings, accruals, and cash flows when firms have large book-tax differences. The Accounting Review 80 (1): 137–166.
Hanlon, M., and G. Krishnan. 2006. Do auditors use information reflected in book-tax differences? Working paper, University of Michigan.
Hanlon, M., E. Maydew, and T Shevlin. 2009. An unintended consequence of book-tax conformity: A loss of earnings informativeness. Journal of Accounting & Economics (forthcoming).
Hayn, C. 1995. The information content of losses. Journal of Accounting and Economics 20: 125-153.
Healy, P. 1985. The effect of bonus schemes on accounting decision. Journal of Accounting and Economics (April): 85-107.
Healy, P., and J. M. Wahlen. 1999. A review of the earnings management literature and its implications for standard setting. Accounting Horizons (December): 365-383.
Holland, K., and Richard H. G. Jackson. 2004. Earnings management and deferred tax. Accounting and Business Research 34(2): 101-123.
Holthausen, R. W. 1990. Accounting method choice: Opportunistic behavior, efficient contracting and information perspectives. Journal of Accounting and Economics 12 : 207-218.
Holthausen, R. W., and R. Leftwich. 1983. The economic consequences of accounting choice: implications of costly contracting and monitoring. Journal of Accounting and Economics 5: 77-117.
Hunt, A., S. Moyer, and T. Shevlin. 2000. Earnings volatility, earnings management, and equity value. Working paper, University of Washington.
Jones, J. 1991. Earning management during import relief investigation. Journal of Accounting Research 29 (2): 193-228.
Joos, P., J. Pratt, and S. D. Young. 1999. Book-tax differences and the value relevance of earnings. Working paper, Massachusetts Institute of Technology.
Joos, P., J. Pratt, and S. D. Young. 2003. Using deferred taxes to detect earnings management: Further evidence. Working paper, Massachusetts Institute of Technology.
Kumar, K. R., and G. Visvanathan. 2003. The information content of the deferred tax valuation allowance. The Accounting Review 78 (April): 471-490.
Lev, B., and D. Nissim. 2004. Taxable income, future earnings, and equity values. The Accounting Review 79 (October): 1039-1074.
Lin and Wu. 2005. Components of the Valuation Allowance of Deferred Tax Assets under Taiwan’s New Income Tax Accounting. Taiwan Accounting Review 6 (1): 29-58.
Lu, J. 2000. The valuation allowance for deferred tax assets and earnings management. Working paper, University of Southern California.
Manzon, G., and G. Plesko. 2002. The relation between financial and tax reporting measures of income. Tax Law Review 55: 175–214.
Matsumoto, D. T. 2002. Management’s incentives to avoid negative earnings surprises. The Accounting Review 77 (3): 483-514.
Maydew, E. 1997. Tax-induced earnings management by firms with net operating losses. Journal of Accounting Research 35 (1): 83-96.
McNichols, M. F. 2000. Research design issues in earnings management studies. Journal of Accounting and Public Policy 19: 313-345.
Miller, G., and D. Skinner. 1998. Determinants of the valuation allowance for deferred tax assets under SFAS No.109. The Accounting Review 73 (2): 213-233.
Mills, L. 1998. Book-tax differences and Internal Revenue Service adjustments. Journal of Accounting Research 36 (2): 343-356.
Mills, L., and K. Newberry. 2001. The influence of tax and nontax costs on book-tax reporting differences: Public and private firms. Journal of the American Taxation Association 23 (1): 1-19.
Mills, L., and R. Sansing. 2000. Strategic tax and financial reporting decisions: Theory and evidence. Contemporary Accounting Research 17 (1): 85-106
Mills, L., K. Newberry, and W. Trautman. 2002. Trends in book-tax income and balance sheet differences. Tax Notes (August 19): 1109–1124.
Mutchler, J. F. 1985. A multivariate analysis of the auditor's going-concern opinion decision. Journal of Accounting Research (Autumn): 668-682.
Phillips, J. D., M. Pincus, and S. O. Rego, and H. Wan. 2004. Decomposing changes in deferred assets and liabilities to isolate earnings management activities. The Journal of the American Taxation Association 26 (Supplement): 43-66.
Phillips, J. D., M. Pincus, and S. O. Rego. 2003. Earnings management: New evidence based on deferred tax expense. The Accounting Review 78 (April): 491-521.
Plesko, G. 2000. Book-tax differences and the measurement of corporate income, in Proceedings of the Ninety-second Annual Conference on Taxation, 171-176. Washington DC: National Tax Association.
Ronen, J., and S. Sadan. 1981. Smoothing Income Numbers: Objectives, Means, and Implications. Boston, MA: Addison-Wesley Publishing Company.
Schipper, K. 1989. Commentary: Earnings management. Accounting Horizons (December): 91-102.
Scholes, M., G. P. Wilson, and M. Wolfson. 1992. Firms’ responses to anticipated reductions in tax rates: The Tax Reform Act of 1986. Journal of Accounting Research 30 (Supplement): 161-191.
Schrand, C., and M. H .F. Wong. 2003. Earnings management using the valuation allowance for deferred tax assets under SFAS 109. Contemporary Accounting Research (Fall): 579-611.
Scott, W. R. 2000. Financial Accounting Theory, 2nd Edition, Prentice-Hall.
Strong, J., and J. Meyer. 1987. Asset writedowns: Managerial incentives and security returns. Journal of Finance 42: 643-661.
Subramanyam, K. R. 1996. The pricing of discretionary accruals. Journal of Accounting and Economics 22: 249-281.
Trueman, B., and S. Titman. 1988. An explanation for accounting income smoothing. Journal of Accounting Research (Supplement): 127-139.
Visvanathan, G. 1998. Deferred tax valuation allowances and earnings management. Journal of Financial Statement Analysis 3 (4): 6-15.
Watts, R. L., and J. L. Zimmerman. 1978. Towards a positive theory of the determination of accounting standards. The Accounting Review 53 (January): 112-134.
Watts, R. L., and J. L. Zimmerman. 1986. Positive Accounting Theory, Englewood cliffs, NJ: Prentice-Hall.
Weber, D. P. 2006. Book-tax difference, analysts’ forecast errors, and stock return. Working paper, University of Connecticut.
Young, S. 1998. The determinants of managerial policy choice: Further evidence for the UK. Accounting and Business Research 28 (Spring): 131-143.
Zucca, L., and D. Campbell. 1992. A closer look at discretionary writedowns of impaired assets. Accounting Horizons 6 (3): 30-41.