在全世界競爭的經濟環境下，各國莫不致力於降低公司租稅成本以增加資金的注入及吸引海外投資。為降低企業稅負，透過租稅天堂進行轉投資儼然成為跨國企業的趨勢。然而，租稅天堂子公司設立的密集度是否會影響公司盈餘管理行為是本文的重點。本文使用台灣經濟新報2005年－2012年財報資料，以台灣上市電子工業公司為研究對象，使用不平衡追蹤資料之固定模型進行估計。本文模型有二盈餘管理模型及有效稅率模型，並且因租稅天堂種類的不同區分成租稅天堂及基地天堂兩情況。 　　模型一盈餘管理模型實證結果發現，租稅天堂及基地天堂子公司密集度向下影響母公司裁決性流動應計數不明顯；然而，在公司有關係人交易情況下，租稅天堂及基地天堂子公司密集度會影響母公司操縱流動應計數的行為，母公司有降低盈餘的租稅動機。模型二有效稅率模型實證結果顯示，母公司當期有效稅率會受租稅天堂或基地天堂密集度影響而下降。最後，同時觀察兩個實證模型的情況一及二可以推論租稅天堂或基地天堂密集度較高的公司，有降低盈餘及租稅成本的租稅動機。

自2005年開始PCAOB對外國之註冊會計師事務所進行國際檢查，至今已逾十年，然而制度實施之初面臨許多質疑。而今，已有文獻指出不論是美國或是其他國家，PCAOB的檢查皆具有一定效益，且具有外溢效果。惟各國間的國家特性因素於目前文獻中尚有發展空間，因此本研究欲了解國家特性是否會影響PCAOB國際檢查的外溢效果。 　　本研究以2004年至2013年間35國的資料計算裁決性應計數，以此代理審計品質，觀察各國審計品質於檢查前後的變化，並以法規執行力以及四大會計師事務所市占率代理國家特性，進一步了解不同特性的國家，其審計品質改變幅度的差異。 　　根據實證結果發現，當一國的法規執行力較高或是四大會計師事務所市占率較高時，審計品質較佳，因此於PCAOB國際檢查後審計品質提升幅度較小。各國的準則制定機構可透過本研究的國家分類，量身訂定更符合國家的準則，以改善審計品質。 / Since 2005, PCAOB has inspected foreign registered audit firms for a period over ten years. The benefits of inspection in both the United States and other countries are documented by extant literature, but the research of country characteristics on the spillover benefits is still lacking. In this study, we document how country characteristics influence the spillover effect of PCAOB international inspection on audit quality. This study uses discretionary accruals as the proxy of audit quality. Our data of non-US-listed companies from 35 countries during 2004-2013 are taken from Datastream. In addition, we use legal enforcement and Big 4 dominance to investigate how country characteristics affect the magnitude of audit quality changes. According to empirical results, we find that countries with higher legal enforcement or Big 4 dominance provide better audit quality. Therefore, PCAOB international inspections in these countries generate smaller magnitude of audit quality improvement than in countries with lower legal enforcement and Big 4 dominance . Our results suggest that regulators of different countries should develop more tailored regulation in order to improve audit quality of their respective countries.

會計盈餘的產生係根據應計基礎，應計會計程序預期會緩和時間性及配合性的問題，而繼美國財務會計準則公報第九十五號公布二年後，國內於民國七十八年十二月發布財務會計準則公報第十七號『現金流量表』，故本研究探討盈餘與現金流量究竟何者較能解釋股票報酬，應計會計程序所扮演的角色為何？本研究首先分析不同累計期間下盈餘與現金流量和股票報酬的關聯性，以及，在不同運用資金的變異性及營業循環期間下，盈餘與現金流量對股票報酬的解釋力，俾瞭解盈餘與現金流量基本財務資料，在投資人決策制定過程中所扮演的角色，以及何者為解釋股票報酬的良好指標。 　　本研究係由探討國內外相關文獻，並參酌國內環境，加以延伸，蒐集民國七十五年至八十二年的資料，以Pooling方法分析，比較盈餘與現金流量和股票報酬的關聯性，進一步使用Vuong Z-statistic從事測試工作。 　　經由實證結果，本研究獲致如下的結論： 　　1、在短的報導期間下，盈餘和股票報酬的關聯性並未較現金流量強，而淨現金流量對股票報酬的解釋力隨著期間的增加而增加。 　　2、在不同的報導期間下，當公司有重大應計數時，盈餘對股票報酬的解釋力並未較現金流量佳。 　　3、當公司及產業的營業循環期間愈長，非現金流量的運用資金變異性愈大，達顯著水準，惟其並不影響盈餘與現金流量對股票報酬的解釋力。

本研究係探析保險業在監理管制下，若有違監理標準之虞時，其經理人是否興起盈餘管理的動機，以避免不必要的監理成本。蓋保險監理最重要的目的為預防保險公司失卻清償能力，以保障被保險人的權益，並維持金融安定。在實施風險基礎資本制前，邊際清償能力的標準仍以保險法第143條第一項之規定為依歸，即保險業認許資產減除負債之餘額，未達實收資本之45%時，主管機關應命其於限期內，以現金增資補足之。若保險業不依第143條規定限期增資補足者，保險法第149條第二項授權主管機關應依情節輕重，分別處以派員監理、撤換負責人或有關人員、限期改組、甚至命其停業或解散。故本研究預期清償能力不佳的保險公司，其經理人會動用裁量性應計項目調整財務狀況，以跨過清償能力標竿，避免受到監理機關的注意與查核。另外，保險法對於保險業資金運用管道有所縮限，以驅使保險公司穩健地運用資金，預防保險公司因巨額投資損失致使清償能力敗壞。但隨著產業競爭度增強與低利率時代的來臨，保險公司在經營績效與保單預定利率的壓力下，是否會安於目前的投資限制，而放棄賺取投資報酬的機會。據此，本研究預期年度中持有短期有價證券總額超過或可能超過35%資金門檻的保險公司，其經理人會選擇處分位於利得部位的短期有價證券，以規避超過保險法第146條之1第一項第二款的門檻限制。同理，年度中持有合格的公司股票及公司債超過或可能超過35%資金門檻的保險公司，其經理人可能會選擇出售位於利得部位的股票或公司債，以規避超過146條之1第一項第三款的門檻限制。 　　在研究設計上，為捕捉各類操縱財務報表的淨影響，本研究採用總裁量性應計項目作為代理變數。在所有可用的裁量性應計項目估計模型中，研究指出Modified Jones模型顯示了相對較強的檢定力(Dechow et al. 1995)。因此本研究援引Modified Jones模型估計裁量性應計數字。其次，將該模型析出的裁量性應計數字與各類監理門檻距離組成一迴歸模型，以測試其關聯性強弱。實證結果如下：一、在產險業，保單持有人盈餘與實收資本之45%的距離愈小者，其盈餘管理幅度愈大。二、壽險業比較沒有利用裁量性應計項目來達到監理標準的動機。但依公司規模來看，大小公司行為仍有所差異，即相較於大公司，小公司利用裁量性應計項目來達到監理標準的動機較為強烈。根據本文實證研究結論，建議監理機關與被保險人應特別注意產險業及小壽險公司的財務狀況，並確認其清償能力之品質。 / This paper examined whether insurance companies have incentives to manipulate accounting accruals to appear more solvent and less risky. In Taiwan, virtually all industries are regulated to some degree, but insurance industry faces regulatory monitoring that is explicitly tied to accounting data. Insurance regulators required that insurers meet conditions for minimum financial health. It is frequency asserted that such regulations create incentives to manipulate financial statement to avoid regulatory intervention The primary hypothesis of this paper is that the incentive to manipulate financial statement is a decreasing function of the insurers’ difference between policyholders’ surplus and 45% of capital. This paper assumes that insurance managers use their reporting discretion to achieve solvency goal and avoid exceeding investment limits. Following Healy (1985), accruals-based measures are wide employed in test of earnings management hypothesis. In the past, the most frequency used techniques for estimating discretionary accruals are the cross-sectional versions of the modified Jones model. In this paper, the magnitude of earnings management is proxied by the discretionary accruals which are estimated by using a cross-sectional version of the modified Jones model and regressed by three differences of regulatory requirements which measure the insurers’ behavior under the regulation. The evidence indicates that when policyholders’ surplus of property-casualty insurers is closer to 45% of capital, the incentive to manipulate financial statement is stronger. On the other hand, life insurers have less incentive to manipulate financial statement, but relative to big size insurers, small size insurers have stronger incentive to meet regulatory requirements.

本研究以我國1994年至2003年由四大會計師事務所查核簽證之上市上櫃公司為研究對象，探討會計師之產業專精與任期及其交互作用對於查核品質之影響，其中以裁決性應計數作為查核品質之代理變數，並同時採用會計師事務所及合夥會計師在特定產業之市場佔有率，作為產業專家之衡量指標。實證結果發現，產業專家可以限制受查客戶透過裁決性應計數從事盈餘管理，而以合夥會計師為基礎所計算之市場佔有率較會計師事務所為基礎所計算之市場佔有率，更能解釋審計品質的差異。在任期方面，研究結果顯示，會計師任期愈長愈能限制盈餘管理，而任期對於裁決性應計數絕對値之影響係反映於任期較長會計師之查核年資。但進一步檢測會計師對管理當局操弄盈餘向上或向下的態度是否隨著任期之增長而有所不同時，本研究發現，當管理當局操弄盈餘使其降低時，會計師任期增長愈能抑制管理當局向下操弄盈餘以預留未來盈餘空間；而在管理當局操弄盈餘使其增加時，會計師任期增長則沒有理由支持具查核品質。此外，在產業專家與任期之交互作用對查核品質影響方面，實證結果發現，產業專家會計師抑制盈餘管理的能力較非產業專家好，所以較不須要透過任期的增加來提升其偵測盈餘管理的能力。 / This study uses the sample comprised of listed and OTC firms in Taiwan during 1994-2003 and examines the effects of auditor industry specialization, auditor tenure and the interaction on audit quality. I use discretionary accruals as proxies for audit quality and industry specialization is measured in terms of both audit firm market share in an industry and auditor market share in an industry. My empirical results provide evidence that industry specialist auditors can restrict accruals-based earnings management and explain the differentiation of audit quality more than industry specialist audit firms. About auditor tenure, I find that absolute discretionary accruals decline with auditor tenure and tenure traced at the longer auditor tenure is superior to shorter auditor tenure. The results show that longer auditor tenure enhances audit quality. In addition, a further analysis shows that the clients have motivations on income-decreasing earnings management, auditors can limit management’s ability to create reserve to manage future earnings. But the clients have motivations on income-increasing earnings management, the study did not provide sufficient evidences to explain that audit quality is improved with tenure. Besides, the result of empirical analysis support my estimation about the interaction between auditor industry specialization and auditor tenure. The industry specialist auditors mitigate earnings management more than nonspecialist auditors and don’t enhance audit quality through extending auditor tenure.

摘要 本文主要檢視中國大陸連續虧損公司面臨下市緩衝機制壓力時之盈餘管理行為。本文所謂的下市緩衝機制係指特別處理(簡稱ST)與特別轉讓(簡稱PT)的管制。具體而言，ST管制要求連續兩年虧損的公司，必須冠上ST標記，漲跌幅限制為5%(一般股票為10%)，中報需審計；PT管制要求連續三年虧損的公司，必須冠上PT標記，同樣有停板限制，僅允許週五交易。ST與PT管制設計原意係希望提高整體市場新陳代謝與營造理性投資的環境，但盈餘基礎的本質與保守的配套措施反而衍生盈餘管理與投機炒股。此下市緩衝機制實質之經濟後果為管制機關與投資大眾高度關注，但過去相關研究相當有限，本文希望藉由下列研究問題的探索以補充文獻缺口。 第一，中國大陸上市公司面臨下市緩衝機制漸進懲處時，管理當局如何進行盈餘管理以因應連續虧損門檻？第二，各群虧損公司次年扭虧次數與盈餘管理行為差異為何？第三，零損失的法規門檻如何引發盈餘分配的特殊型態；操控前盈餘與盈餘管理關係為何？ 依據1998年至2000年267家虧損公司樣本，實證結果簡要彙總如下：第一，虧損公司裁決性應計數字(營業外所得)顯著降低盈餘，特別在虧損第一個年度，此結果顯示管理當局意圖儲存盈餘以因應未來更嚴格制裁之緩衝。第二，ST股與PT股盈餘劇烈震盪，其盈餘型態分別呈現V字型與W字型。第三，1998與1999年連續三年虧損的公司次年扭虧百分比小於其他虧損公司；但2000年結果相反。主要理由乃中國證監會於2001年2月22日要求PT股在未來一年扭虧(過去為三年)，否則必須下市。第四，虧損公司次年盈餘分配集中於略高於零損失門檻的區間，隱含實質小虧的公司預支未來盈餘，實質大盈的公司儲存本期盈餘的可能性。第五，虧損公司次年扭虧時，操控前盈餘與盈餘管理呈現負向關係，且操控前盈餘越小的組別其盈餘管理越大。但持續虧損公司操控前盈餘與盈餘管理的關係並沒有系統性的結論。 本文實證結果顯示，中國大陸下市緩衝機制由於仰賴會計基礎管制，衍生相當普遍的盈餘管理行為。建議中國證監會應在下市決策中考量非盈餘資訊，投資大眾亦應關注盈餘以外的訊息以避免功能固著的迷失。 / Abstract This study investigates earnings management of Chinese listed companies subject to delisting buffer mechanism for reporting losses for consecutive years. The delisting buffer mechanism in China means Special Treatment (ST) and Particular Transfer (PT) regulations. Specifically, it requires that companies with two and three consecutive losses be labeled as ST shares and PT shares respectively. ST shares are subject to 5% price limits (one half of common shares) and their interim reports should be audited. PT shares are also subject to price limits and they are allowed be traded only on Friday. Although these regulations originally aim to maintain market’s metabolism and foster rational investment environment, their earnings-based nature and conservative schemes are likely to induce pervasive earnings management and speculation. Their economic consequences are a source of concern by regulators and investors, but previous study is relatively limited. Thus, this paper explores the following research questions to fill this void. First, how do Chinese listed firms manage earnings in response to consecutive loss thresholds, while facing the progressive sanctions of the delisting buffer mechanism? Second, what differences in positive earnings frequencies and earnings management exist among different group of loss firms in the following year? Third, how does the zero-loss regulatory threshold induce specific types of earnings distribution, and what relationship can be found between pre-managed earnings and earnings management? Based on a sample of 267 loss firms from 1998 to 2000, the empirical results are briefly summarized as follows. First, discretionary accruals (nonoperating income) of loss firms show significant earnings decreases, especially in the initial loss year, which is consistent with managerial incentives to save earnings for future more severe regulations’ cushion. Second, ST shares and PT shares experience large earnings volatility, and the patterns of ST shares and PT shares’ earnings generally look like V and W respectively. Third, percentage of positive earnings of firms with 3-year losses in the following year is less than that of other loss firms in 1998 and 1999, but more than in 2000. The underlying reason is the Chinese Securities Regulatory Committee requires PT shares have positive earnings within the next year rather than next three years after Feb 22, 2001, otherwise they are delisted. Fourth, earnings distribution of loss firms heavily clusters slightly above zero-loss threshold in the following year, which implies firms with small latent losses likely to borrow future earnings and firms with large latent earnings likely to save current earnings. Fifth, the pre-managed earnings and earnings management for loss firms reporting profits in the following year are negatively correlated. Furthermore, the smaller the pre-managed earnings are, the larger the earnings management is. However, the data reveal no systematic relationship between pre-managed earnings and earnings management for firms with persistent losses. Overall, the empirical results indicate that China’s delisting buffer mechanism, relying mainly on accounting-based regulation, induces pervasive earnings management. The findings therefore suggest that the Chinese Securities Regulatory Committee should consider non-earnings information into delisting decisions and investors look beyond bottom-line to avoid functional fixation.

近幾年來，財務弊案層出不窮，管理當局參與創造性會計的情事日益嚴重，資本市場陷入紀律危機，徒增成本。為喚醒投資者對於盈餘品質的關注，以及對盈餘管理有更客觀的瞭解，本研究提出兩種不同基礎之盈餘品質分類法，並探討台灣上市公司在盈餘品質分類法下，財務特性與盈餘管理成分的差異。 以往國內文獻多個別探討盈餘品質的內涵，或盈餘管理的現象；將盈餘品質與盈餘管理兩大主題做結合，乃新嘗試。研究主要分為兩大部分，第一部份定義盈餘品質，而第二部分深入盈餘管理的課題。 研究以2002年第3季到2004年第3季，381家台灣上市公司，共3429個樣本點，進行迴歸模型分析。 首先將樣本以：一、盈餘對營運現金流量的關係，及二、應收帳款成長率對營收成長率的比較，共兩種基礎，區分盈餘品質。在區分盈餘品質後，以盈餘品質測試盈餘評價能力與持續性。發現以盈餘對營運現金流量關係作為基礎之盈餘品質，具有增額評價能力，而以應收帳款成長率對營收成長率的比較做為基礎者，無增額評價能力。而兩種盈餘品質對盈餘持續性有顯著貢獻。 第二部分將樣本分為盈餘平滑企業與非盈餘平滑企業，探討盈餘評價功能之強弱，發現在盈餘平滑與盈餘非平滑兩組別中，盈餘平滑化並不影響盈餘評價能力。接著導入盈餘品質，觀察在交叉分組下盈餘評價功能的差異，發現高盈餘品質結合盈餘非平滑化（Quality Non-Smoother）的組別中，有最高盈餘評價係數。盈餘進一步拆解成三個組成份子：營運現金流量，裁量性應計數，與非裁量性應計數。其中，觀察重點在於裁量性應計數，研究同樣加入盈餘品質，測試其評價能力與持續性。發現裁量性應計數具有評價功能，而在兩種盈餘品質指標分類下，高盈餘品質之裁量性應計數，並無增量評價貢獻；在持續性方面，兩種盈餘品質指標同樣對裁量性應計數有正向貢獻。 為測試盈餘品質在盈餘管理誘因下的反應，最後將盈餘管理誘因區分為達成損益兩平與超越前期盈餘兩項目標，並加入盈餘品質，觀察其交互作用。發現在「達成損益兩平」與「超越前期盈餘」兩種盈餘目標下，盈餘管理現象的確存在。加入盈餘品質變數後，在兩種盈餘品質變數之作用下，對「達成損益兩平」與「超越前期盈餘」兩項管理誘因均有抑制作用。 / During the last few years, there have been numerous cases of financial ma-nipulation and scandals of firms and the situation of the managing authority par-ticipating in creative accounting has become worsen which has posed enormous disciplinary risks and unnecessary costs on the entire capital market. In order to invoke the concern of investors towards earning quality and to objectively under-stand more broadly about earning management, this study focused on two dif-ferent earning quality categorization based on different basis. The other aim of this study was to discuss the differences of financial characteristics and earning management that arise under two different earning quality categorizations. Most of the local existing literature discussed separately on the essence of earning management or the phenomenon of earning management; this study would be a completely new attempt, which combined the above-mentioned two topics into one study. The first part of this study focused on the definition of earn-ing quality and the second part discussed in detail on issues concerning earning management. A regression analysis was conducted on 381 publicly listed firms in Taiwan during the period from the third quarter of 2002 to the third quarter of 2004 and the total sample points were 3429. Firstly, the samples were processed and the samples’ earning qualities were categorized based on: 1. the comparison between earning and operating cash flow; 2. the comparison between the growth rate of account receivables and the growth rate of revenue. After the categorization of earning qualities, earning qual-ity was used to test the ability of earning valuation and the persistence of the earning. It was revealed in this study that the earning quality based on the com-parison between earning and operating cash flow could greatly enhance the abil-ity of earning valuation. On other hand, the earning quality based on the compari-son between the growth rate of account receivables and the growth rate of reve-nue failed to enhance the earning valuation. However, both categories of earning qualities had significant contribution to the persistence of earning. The second part of the study separated the samples into earning smoothing firms and non-earning smoothing firms in order to discuss the power of the ability of earning valuation. The results showed that earning smoothing did not have any impact on ability of earning valuation. The next step was to introduce earning quality into this part of the study and to observe the differences in the ability of earning valuation that arise from cross grouping. It was revealed that the group of high earning quality combining non-smoother had the highest earning valuation coefficient. Earning was further decomposed into three components: operating cash flow, discretional accruals and non-discretional accruals. The focus was on the observation of discretional accruals, and in this part of the study, the earning quality was also introduced in order to test the ability to valuate and the persis-tence of earning. It was discovered that discretional accruals possessed the func-tion of valuation. Furthermore, under the categorization of earning quality indexes with two different bases, discretional accruals with high earning quality had no contribution toward the ability to enhance valuation; however, about the persis-tence, both earning quality indexes had positive contribution toward discretional accruals. Finally, in order to test the reactions of earning quality under the influence of the incentives of earning management, the incentives of earning management were categorized into two groups with two different goals: 1. to reach breakeven; 2. to exceed prior period earning. The earning quality was also introduced to ob-serve the interactions. It was observed that under the two different goals in earn-ing, the phenomenon of earning management did indeed exist. After including the variable of earning quality, under the influences of two different categories of earning quality variables, there was some kind of suppressive effects on the management incentives of “reaching breakeven” and “earning that surpasses the prior period earning”.

本研究係以裁量性應計數字及其組成成分衡量盈餘管理，以審計人員產業別市場佔有率與產業別客戶集中度之綜合衡量捕捉審計品質，探討不同樣本公司之盈餘管理特性，以及審計品質對不同盈餘管理特性之影響。管理者對應計項目的認列通常有某種裁量權，此裁量權可用以顯露私有資訊而增進盈餘的價值攸關性，或可投機性地管理盈餘而減低盈餘為公司績效衡量的可靠性。所以探究盈餘管理行為是增加財務報告資訊性(information)或雜訊(noise)即非常重要。研究內容依盈餘管理特性區分為投機性盈餘管理與訊息發放性盈餘管理二大部分。每一研究內容則是先辨認盈餘管理本質，其次探討審計品質對盈餘管理之影響。在研究設計上，為避免實證代理變數之衡量誤差重大影響結果，乃採用實驗組公司與控制組配對公司相比較，以凸顯出前者之盈餘管理型態。 　　研究結果顯示，門檻公司從事盈餘管理以達前期盈餘門檻，且此盈餘管理不具未來現金流量持續性之涵義，係符合「隱藏當期不利績效、遞延本期不尋常盈餘至未來年度」以減低會計盈餘數字波動性之特性。就自願性盈餘預測此一資訊揭露工具而言，在盈餘預測偏屬樂觀之傾向下，仍有管理者自願揭露壞消息預期，即可知管理者之誠意，不失為一可資信賴之訊號。但自願預測盈餘增加，則不必然具有高公信力。甚至在管理者降低盈餘差距之動機下，易引起管理者操縱盈餘。此為財務報表使用者所需注意。就持股變動此一資訊揭露工具而言，在我國家族企業居多之情形下，增加持股並未代表任何特定之涵義。反而是減少持股所透露之訊息，值得投資人注意，尤須慎防其盈餘操縱行為。 　　面對增加所得之裁量性應計數字，審計品質有效阻止投機性盈餘管理。面對顯露私有資訊之盈餘管理，審計品質能夠協助管理者選擇最能彰顯未來現金流量預期之會計方法，以增強裁量性應計數字與未來現金流量變動之關聯性。在高審計品質所賦予之資訊公信力下，盈餘資訊在投資人之決策過程中有一定之重要性，故投資人發現裁量性應計數字增加（減低）盈餘價值攸關性，因而增加（減低）盈餘評價係數。然而對低審計品質所查核的財務報表，較低的資訊公信力，使盈餘未在投資人評價過程中扮演重要角色，因而盈餘管理特性亦不受投資人重視。 / This research examined characteristics of earnings management and effects of audit quality therein. Specifically, the magnitude of earnings management was proxied by the discretionary accruals, which are estimated using a cross-sectional version of the Jones model. Different from prior research, the audit quality was captured by a combined measure of the auditor's market share and client concentration. The market share measured the auditor's competence (industry specialty) and the client concentration measured the auditor's independence. Managers usually exercised discretion to recognize accruals. They could either signal private information to enhance earnings' value relevance, or opportunistically manage earnings to reduce the reliability of earnings as the performance measure of the firm. As a result, it was important to examine earnings management and to identify whether it would increase the informativeness or noise of financial reports. This study was organized according to the characteristics of earnings management: opportunistic earnings management and signaling earnings management. For both parts, the nature of earnings management was identified first, and then the effects of audit quality therein examined. To reduce the impact of measurement errors of proxy variables, the treatment group and controlled group were compared and contrasted to make earnings management pattern of the treatment group more evident. 　　The results showed that threshold firms managed earnings to sustain last year's earnings level. Discretionary accruals of the threshold firms were not significantly associated with future cash flow changes. Those discretionary accruals were used to hide the current unfavorable performance, or to defer current unusual earnings to the future, so that managers could reduce the volatility of accounting earnings. As a means of information disclosure, voluntary earnings forecasts tended to be optimistic, but we still could observe some voluntary forecasts which decreased earnings. In those situations, we might conclude that managers tried to convey credible signals. However, it was not necessarily credible in the case of voluntary forecasting which increased earnings. Managers would manipulate earnings to reduce the difference between forecasted earnings and reported earnings. In respect of the information signal of changes in directors' share holding percentages, it signaled nothing when directors increased holding percentages because most companies were family businesses in Taiwan. Nonetheless, investors should look out the possibility of earnings manipulation when directors decreased their holding percentages. 　　Audit quality could effectively deter opportunistic earnings management but not the income-decreasing discretionary accruals. Based on information signaling perspective of earnings management, auditors with higher audit quality tended to assist managers to choose accounting methods that might signal cash flow expectations. Stronger associations between discretionary accruals and future cash flows were observed for firms audited by higher quality auditors. Because higher audit quality might increase information credibility, earnings would play a more important role in the decision process of investors. When discretionary accruals increased (decreased) earnings' value relevance, earnings association coefficients would be increased (decreased). However, for the financial reports audited by lower quality auditors, earnings did not play an important role in the valuation process because of lower information credibility. Therefore, empirical results showed that investors of firms audited by lower quality auditors did not make decisions according to different characteristics of earnings management.