The development of modern financeFirst, the financial problem of the uncertainty(A) the uncertainty of the field in the application of asset pricing1. Portfolio Theory and Capital Asset Pricing ModelIn the framework of the financial analysis, introduction of the concept of uncertainty is a major role. First Kenes (1936) and Hicks (1939) proposed the concept of risk compensation that the financial products in the presence of uncertainty, should interest rates in different financial products in compensation for additional risks. Subsequently, Von Neumann (1947) applied the concept of expected utility of the proposed settlement in the decision-making under uncertainty in the method chosen, on this basis Markowiz (1952) developed a portfolio theory, he thought when investors choose portfolio concerned only with future cash flow of the mean and variance. He assumed that the expected utility of investors consistent with secondary distribution or multinomial distribution. Markowiz The main conclusions are subject to uncertainty, optimal decision-making is a diversified investment holding. Tobin (1958) that investor liquidity preferences for their own benefits and risks of different options for the balance. This further improved the framework of portfolio choice the field of asset pricing model is another well-known theory of capital pricing model (CAPM), Sharp (1994) and Lintner (1995) using the formula succinctly expressed the portfolio value and risk-free interest rate and the level of risk assets, the relationship between . Black (1972) introduced even in the non-risk assets zones remained the case, Sharp and the CAPM formula is still valid, just without the risk of interest rates are including the entire market on all assets of the portfolio rate of return instead of the 预期. Contemporary with the CAPM model of the asset pricing model also Ross (1977) arbitrage pricing model (APT) and Lucas (1978) the typical agent asset pricing by CAPM asset pricing model for asset pricing provides a simple method of calculation, and obtain some support from empirical studies (Fama and Macbeth, 1973), but in reality some of the anomalies is still a lack of effective explanatory power, Brennan (1989) that the CAPM is based on the expectations of all investors in the investment and risk are common in estimates and judgments, and all investors the same utility function based on the assumption that this assumption is inconsistent with the reality This is leading to some practical problems CAPM on the root causes of the lack of explanatory power. It is beyond doubt on these assumptions, to promote the introduction of the concept of asymmetric information and . Market efficiency hypothesisMarket efficiency hypothesis that in a perfectly competitive market, there is no asymmetric information and market frictions affect the future earnings of the average investment risk is different. 60s in the 20th century a large number of research workers on the market efficiency hypothesis was tested, Fama (1973) through empirical tests on the . stock market, that the efficient market hypothesis holds, but many researchers found that in the market, There are many market efficiency hypothesis or CAPM model can not explain the abnormal phenomenon. For example, Basu (1977) found that the average earnings assets, in addition to the β coefficient of the CAPM, but also with the price earnings ratio of assets (P / E ratio) is related to the same β coefficient, the higher the price earnings ratio stocks (growth stocks) better than the market price of the low price earnings ratio of stocks (value stocks); Benz (1981) found that the market price of the stock with the size of the listed company; Stattman (1980) found that stock prices and the ratio of book value (P / B ratio) is also an important factor affecting stock prices. Fama and French (1993) On the basis of the above three-factor model proposed that the impact of asset prices in the β factors, joined the P / E ratio and P / B ratio interpretation of these anomalies, the efficient market hypothesis seems powerless, someone had tried the "January effect" to the end of Shuishou interpreted as the impact of outflow, but in the United Kingdom, Australia, the annual revenue of the country is not in December, there are still "in January effect "can not be explained. Some scholars from a psychological perspective to explain these anomalies, such as, Dreman (1982) the stock price P / E ratio effect interpreted as the investor always overestimate growth stocks with high growth, leading to market high P / E ratio of stock market was overvalued, that it is a reason for low stock . Continuous time modelIn asset pricing theory is another important assumption: stock market is always in a continuous process, under this assumption, Merton (1969,1971) to develop instantaneous CAPM Capital Asset Pricing Model (ICAPM), the same information symmetry, frictionless market, asset price changes in line with Ito process under these conditions, asset prices and investor preference for independent effectiveness. In subsequent studies Merton (1973) and Black (1973) The application of these continuous-time model has been successful in the option pricing formula, the formula was later confirmed that a large number of empirical studies and has been widely applied in practice.(B) the uncertainty of financial management in the company ofFinancial analysis is another important area of financial management, major research firms in the investment decision-making in the proportion of the debt and equity options, the company's dividend policy and other issues. Results of the first studies in this area by the Modigliani and Miller (1958) made their study shows that full market (no market frictions and asymmetric information exists) the value of the company has nothing to do with the company's debt ratio (MM theorem). A similar study concludes that the value of the company's profit distribution policy has nothing to do. Obviously, these research findings and practical in reality. MM theorem based on the conclusions in the distribution of profits, due to the cash outflow will be sent found Jinhong Li, the Company repurchased shares will be more willing to choose policies, rather than the dividend policy, in reality, many companies prefer to dividends rather than Share buy-back, this phenomenon is Black (1976) referred to as "Company dividend puzzle (Dividend Puzzle)", which Miller (1977) can give the explanation, MM theorem conclusion is that the reason and the reality of different tax and the so-called bankruptcy costs on the financial structure is the result of certain liabilities of the company can achieve the role of tax relief, another company because of the existence of high debt ratio risk of bankruptcy, so the debt ratio to the value of existing shares affected, Miller and Other scholars make on these financial problems are not very satisfactory interpretation of the whole until later after the introduction of asymmetric information, it seems Caidui explain these issues to achieve a mentioned above, some of the phenomena of reality is difficult to simply use the uncertainty (risk) to get a satisfactory explanation, it is in the research of these issues raises the question of asymmetric information on financial concerns, plus last 60 years in the 20th century to game theory, represented a breakthrough in the information economy research methods, leading many scholars to the financial problems of asymmetric information in the study achieved a lot, especially the use of asymmetric information can explain a lot of perfectly the financial structure issues. Following is an overview of this still results in two parts, first in the results of financial decision-making, followed by the asset pricing results.(A) asymmetric information in corporate financial management application