由於資產的減損會大幅影響會計盈餘與資產價值，且一般公認會計原則給予公司管理階層在資產減損的處理上有很大的彈性，因此長久以來，長期性資產減損的議題都吸引著經理人、會計資訊使用者、媒體、政府規範單位以及學術界的注意。美國財務會計準則委員會在2001年10月發佈了財務會計準則第142號與第144號公報來修正原本規範長期性資產減損的第121號公報，其中第144號公報主要規範的資產類別為非商譽類的長期性資產減損會計處理。雖然144號公報施行至今已有數年的時間，但與144號公報相關的實證研究極少，因此本文將時序拉回公司採用144號公報的首年度，分析公司認列長期性資產減損的決定性因素以及股票市場對公司資產減損宣告的反應。 在公司認列長期性資產減損的決定性因素方面，實證分析結果顯示公司長期性資產減損之金額會受到公司之經濟因素（股票報酬、資產報酬率成長率）以及報導動機（總資產、盈餘平穩化、經理人變動）影響，由此可知公司認列資產減損的行為與動機除了包含144號公報內所規範的經濟因素外，尚包括傳統盈餘管理理論中所提出的報導動機。 而在分析股票市場對公司資產減損宣告反應的研究中，先前的研究均是假設市場上對於資產減損的認列為非預期的，然而市場上對於資產減損損失的認列並非全然皆為非預期的，投資人亦有可能透過公開資訊的蒐集以及理性分析後會將預期資產減損損失考慮在投資策略中；因此本文利用迴歸模型預測，將長期性資產減損分為投資人預期與非預期兩種類型進行分析，以分別探討投資人對預期與非預期的資產減損宣告有何不同的反應。實證結果顯示，不論資產減損是否被投資人預期，股票市場對於資產減損的消息並沒有顯著反應。

Because of the non-recurring and transitory nature of discontinued operations, accounting standards require that the results of discontinued operations be separately reported on the income statement. Prior accounting literature supports the view that discontinued operations are non-recurring or transitory in nature, and also suggests that income classified as transitory has minimal relevance in firm valuation. Finance and management literature, however, suggest that firms discontinue operations to strategically utilize their scarce resources. Assuming that discontinued operations are a result of managerial motives to strategically concentrate resources into remaining continued operations, this dissertation examines the informativeness of discontinued operations. In doing so, this dissertation empirically tests the financial performance, investment efficiency, valuation, and analyst forecast accuracy effects of discontinued operations. In 2001, Financial Accounting Standards Board's (FASB) Statement of Financial Accounting Standards (SFAS) 144 (hereafter SFAS 144) replaced Accounting Principles Board's Opinion 30 (hereafter APB 30) and broadened the scope of divestiture transactions to be presented in discontinued operations. Some stakeholders of financial statements argued that discontinued operations were less decision-useful in the SFAS 144 era because too many transactions that do not represent a strategic shift in operations were separately stated as discontinued operations on the income statement. With the possibility that the discontinued operations reported in SFAS 144 era may not reflect a major strategic reallocation of resources, this dissertation examines whether the relationship between discontinued operations, firm performance, investment efficiency, and analyst forecast accuracy are different in the pre-SFAS 144 and SFAS 144 era. Using a sample of firms that discontinued operations between 1990 and 2012, this dissertation study finds limited evidence that firms experience improvement in financial performance following discontinued operations and that such improvement is only observed in pre-SFAS 144 era. The results also suggest that any improvement in financial performance documented is conditional on the profitability of the operations discontinued and provide no support for investment efficiency improvement following discontinued operations. Related to the valuation implications of discontinued operations, this dissertation shows that investors differentially value profitable and loss discontinued operations. However, such valuation differences are not dependent on the performance improvement implications. Finally, results support that analyst forecast accuracy of earnings decreases following the reporting of discontinued operations, but such effect is only observed in the pre-SFAS 144 era. This dissertation makes several contributions to the literature. First, this study extends the literature on corporate divestment by using a large sample of discontinuation decisions and hand-collected data on the profitability of the operations discontinued. Second, this research extends the literature on market studies by analyzing whether market response to a discontinuation decision is dependent upon the profitability of the operation discontinued. Third, based upon a review of the literature, it is believed that this is the first study to examine the possibility that analyst forecast accuracy may change following a discontinuation decision. Finally, this study extends the literature that examines the effects of changes in accounting rules and regulations on the informativeness of financial statement items. These results should be of interest to investors, regulators, and analysts.