مجله پیشرفت های حسابداری
سال چهارم شماره 2 (پیاپی 63، پاییز و زمستان 1391)

Undoubtedly discovering trends in the market and earn returns is one of the important issues from the perspective of an investor. Discovering the hidden angles, is very attractive. Abundant empirical evidence worldwide suggests that repeating patterns over time is possible. This efficient market concept and theories associated with it, is not compatible with the concept of performance based foundation of modern theories of financial market as the unpredictable behavior of the market has been long established. There are exceptions to the financial markets that show deviations from the rules of logic and rational that is in violation of efficient markets. One of these exceptions, "seasonality or calendar anomalies", is that certain patterns existing at different years, months, weeks and days will be approved. Irregularities include calendar, asymmetric distribution of returns in the days and months. Research hypotheses 1. The stock returns in December are different from the stock returns in other months in Tehran stock Exchange. 2. The stock returns in April are different from the Stock returns in other months in Tehran stock Exchange. 3. The stock returns on Saturday are different from the Stock returns on other days in Tehran stock Exchange. 4. The stock returns on Wednesday are different from the Stock returns on other days in Tehran stock Exchange. 5. There is a significant relationship between GDP variations and extraordinary return of season. 6. There is a significant relationship between inflation and extraordinary return of season. 7. There is a significant relationship between annual stock returns and extraordinary return of season. 8. There is a significant relationship between extraordinary efficiency risk (deviation of stock returns) and extraordinary return of season. To evaluate the relationship between stock returns and the months of H0 and H1 hypothesis, we used: H0: M1 = M2 H1: M1 ≠ M2 M1: The percentage of average daily stock returns in the month M2: The percentage of average daily stock returns in the remaining months To study the relationship between stock returns and days of a week and also the hypotheses H0, H1, we use: H0: D1 = D2 H1: D1 ≠ D2 D1: The percentage of average daily stock returns of the desired day [[ D2: The percentage of average daily stock returns in the rest of days a week To evaluate the relationship between changes in GDP and inflation wonderful seasonal efficiency of multiple regressions, we use the following: To evaluate the relationship between changes in GDP and inflation wonderful seasonal efficiency of multiple regressions in next year, we use the following: Result 1. There is no January effect in Iran. 2. The stock returns in December are different from the stock returns in other months in Tehran stock Exchange. 3. The highest stock returns between days of a week for Iran as for European and American countries are on Wednesday. 4. The lowest stock returns between days of a week unlike European and American countries are on Sunday. 5. The highest Stock returns in seasons belong to summer and the lowest belong to the winter. 6. The highest stock returns belongs to the first half of the year and the lowest belong to the second half of the year. 7. There is no significant relationship between GDP variations and extraordinary return of season. 8. There is no significant relationship between inflation and extraordinary return of season. 9. There is no significant relationship between annual stock returns and extraordinary return of season. 10. There is no significant relationship between extraordinary efficiency risks (Deviation of stock returns) and extraordinary return of season. Based on the results we find that Macro Variables of Economic does not effect season extraordinary return and we know some days and some months have extraordinary return that effect investors’ investing.

One of the main problems of choosing a portfolio which consists of stocks or assets is to consider their incongruous nature with a view to risk, return and liquidity. In other words, the inability to choose an optimum portfolio considering risk, return and liquidity at the same time is a problem. Hence, financial decision makers in order to have access to optimum portfolio have to trade off some of the mentioned criteria, inevitably. Various approaches have been utilized to resolve this problem. One of the models which is expressed recently and categorized as a nonparametric frontier model is data envelopment analysis. DEA can resolve the mentioned problem by measuring and assessing the efficiency of a portfolio. In this research liquidity is added to risk and return to identify its impact in choosing optimum portfolio. This means that if considering stock liquidity as a criterion in choosing optimum portfolio leads to a better result the investors must consider it. This study is accomplished by using DEA. Research Questions or hypotheses Based on the goals of this research which are 1) the study of stock liquidity influence in choosing portfolio and 2), DEA usefulness on choosing portfolio, hypotheses are expressed as follows. To have access to the first goal, the first hypothesis is as follows: H1: There are significant differences between two portfolio's return when one of them is chosen by DEA technique and considering risk, return and liquidity rank and the other one which does not consider these three variables. And to achieve second goal, the second hypothesis is expressed as follows: H2: There are significant differences between two portfolio's return when one of them consists of 30 companies are located at the first rank of efficiency point and the other one which consists of 30 companies are located at the last rank with view to efficiency point (The first portfolio is chosen by using DEA technique and the other one is not). At first in order to test the hypotheses, efficiency point is calculated by using DEA in two different situations. 1) Risk and liquidity rank are considered as input variables and return as output variable of DEA technique. 2) Risk is considered as an input variable and return as an output variable of DEA technique. Then significant differences of both hypotheses are tested by using t-test. It is important to notice that the number 30 is chosen to improve the results validity. DEA can be utilized by using BCC or CCR models. In this research the chosen model is BCC. As mentioned above and by using t-test, first hypothesis results show that there is not a significant difference between two portfolios’ return. Testing the second hypothesis suggests that there is a significant difference between the two portfolios’ return. This result reveals the usefulness of using DEA technique in choosing optimum portfolio. Discussion and This research is set up to study the influence of stock liquidity and DEA usefulness in choosing optimum portfolio. In comparison with Eslami Bidgoli and Saranj (1387) results show that stock liquidity could not be considered as influence criterion and decision makers do not consider it in the process of choosing optimum portfolio. Although, according to the results it is taken for granted that in Tehran Stock Exchange sufficient information about stock liquidity are not published. Moreover, the results essay that using DEA technique in choosing optimum portfolio is efficient.

A critical challenge for companies is how to sustainably supply the required cash for ongoing current activities and long term capital investments. This required cash is supplied by internal sources such as retained earnings as well as by external sources such as new issued debt and capital. Although financing methods are affected by various and numerous internal and external factors, recent studies show that the most important factor which affects financing affairs is financial flexibility and this financial policy is going to be the dominant pattern in financing strategy. Research Question: The research questions are as follows: 1) Does financial flexibility have a positive impact on firm’s investment? 2) Does financial flexibility have an impact on value enhancing? So research hypotheses are as follows: 1) Financial flexibility has a positive impact on firm’s investment. 2) Financial flexibility has an impact on value enhancing. Research In this research we use spare (unused) debt capacity to measure financial flexibility. Our criteria for measuring investment and value enhancing are capital expenditure and stock return, respectively. Then, we have used multiple regressions to assess the relationship between the research variables. Our sample consists of 77 Tehran stock exchange firms and the sample period is during1999-2010. Despite our expectations the results show that financial flexibility doesn’t have a positive impact on investment. This finding indicates that first research hypothesis about positive impact of financial flexibility on investment, is rejected. Other results show that financial flexibility has an important positive impact on firm’s value enhancing and financial flexible firms are valuable from market participants and investor’s point of view. By this finding, research hypothesis about impact of financial flexibility policy on value enhancing is accepted. Discussion and In this paper, we studied the interaction between financial flexibility and investment. Despite o our expectations, the results suggest that financial flexibility significantly has a negative impact on capital investments, thus, our results are in contrast to theoretical basis as well as works of Arsalan (2009) and Marchica and Mura (2010), but our result is consistent with the Iranian works of Khodaee and Zare (2010) in which they argued that in Iranian stock market financial flexibility has no impact on capital investments decisions. In addition, we performed a long-run performance analysis to test whether financial flexibility policy is genuinely value enhancing. The results of our study related to the association of financial flexibility and value enhancing reveals that α coefficient (which shows the effect of unique properties on return) is not equal between the companies which are financial flexible and non-financial flexible. It is high and positive in financial flexible firms and it is low and negative in non-financial flexible firm which is consistent with the Marchica and Mora (2010) study. This result suggests why the majority of companies are using this approach in financing of their operations.

Being aware of the financial situation of the firm and being more familiar with investors and creditors, managers as those who are responsible for providing financial statement, try potentially to make a good picture of the firm’s conditions. Therefore, they tend to delay the disclosure of bad news and identify the good news as soon as possible. Manager’s tendency to hide bad news causes stock price crash risk and generally negative skewness of stock return. Conservatism as a governing mechanism, through enforcing the possibility of asymmetric confirm for recognizing earning and losses, results in the acceleration of identifying bad news versus good ones. Consequently, it prevents piling of bad news in the company and decreases possibility of sudden releasing of bad news in the market. Research Questions or Hypothesis The main purpose of the present study is to investigate the relationship between conditional conservatism in financial reporting and the future stock price crash risk. To do this, two main hypotheses and three subsidiary ones were specified. The hypotheses of this research are as follows: H1: conditional conservatism in financial reporting reduces the future stock price crash risk. H2: the impact of conditional conservatism on reducing future stock price crash risk is greater for firms with higher information asymmetry. To test second main hypothesis, the following three subsidiary hypotheses were specified. H2a: the impact of conditional conservatism on reducing future stock price crash risk is greater for firms that operate in monopoly markets. H2b: the impact of conditional conservatism on reducing future stock price crash risk is greater for firms that have no institutional investors in their ownership structure. H2c: the impact of conditional conservatism on reducing future stock price crash risk is greater for firms that have lower than 50% outside directors on their board. To test the hypotheses, a sample was selected among the listed companies in Tehran stock exchange (TSE) during 1380-1388(2001-2009). Also, to measure conservatism, the measure of conditional conservatism by Khan and Watts (2010) was used and the method of logistic regression and the model of pooled data were applied. To examine the significance of all resulting coefficients, t-test and z-test were used. The results of estimated models showed that, there is a negative relationship between conditional conservatism and future stock price crash risk. So, the first main hypothesis is not rejected in confidence level of 95%. The results also showed that when there is a sort of information asymmetry among managers and outside investors, the ability of conditional conservatism for decreasing future stock price crash risk is more. So, the subsidiary hypotheses and the second main hypothesis are not rejected in confidence level of 95%. Discussion and In this study, the relationship between conditional conservatism and future stock price crash risk of companies listed in TSE were investigated. Findings of this research showed that conditional conservatism in financial reporting; reduce future stock price crash risk. In other words, conservative accounting prevents the accumulation of bad news through enforcing managers to timely disclosure of such news. Hence, conservative accounting decreases the probability of sudden releasing of bad news in the market and consequently reduces future stock price crash risk. Results also showed that, the ability of conditional conservatism to reduce future stock price crash risk is greater for firms with higher information asymmetry. Namely, those operating in monopoly markets, have no institutional investors in their ownership structure and have lower than 50% outside directors in their board. When there is information asymmetry, managers have incentives to delay the disclosure of bad news and accumulate them within the firm. Given that information asymmetry results in conservative accounting, one could expect that, for firms with higher information asymmetry, the ability of conditional conservatism to reduce future stock price crash risk is greater.

In the current business ownership structure, separation between managers and shareholders is unavoidable. In these firms, failure to monitor the management may lead to inefficient resource allocation and to some extent, corporate scandals (Johari et al., 2008). In this study we investigate the relationship between board characteristics and firm performance. Hypotheses H1: There is a significant relationship between the presence of non-executive directors in the board’s structure and firm performance. H2: There is a significant relationship between chairman duty separation from CEO and firm performance. H3: There is a significant relationship between number of board members and firm performance. H4: There is a significant relationship between changes in board members or their agents in current year relative to prior year and firm performance. H5: There is a significant relationship between gender diversity in the board and firm performance. H6: There is a significant relationship between institutional ownership and firm performance. In this research, return on assets (ROA) is considered as proxy for firm performance. Control variables in this study include firm size, operation cash flow and leverage. Research samples are 159 firms (954 year -firm) on Tehran Stock Exchange (TSE) during 2003 to 2008. In this study fuzzy regression is used for testing the hypotheses. Research results show that there is a negative relationship between nonexecutive managers and firm performance. Results also show that, chairman duty separation from CEO and number of board members has a negative association with firm performance. Thus H1, H2 and H3 are accepted. Results show that there is a positive relationship between changes in board members and firm performance. Thus H4 is accepted. In this research, gender diversity has a negative association with firm performance. Thus H5 is accepted. Research results indicate that there is no significant relationship between institutional owners and firm performance. Thus H6 is rejected. Regressed model results show that firm size and operation cash flow have a positive relationship with firm performance. Results also show that there is negative relationship between leverage and firm performance. Discussion and This paper examined the roles of board characteristics on firm performance. The fuzzy regression was applied to test the research hypotheses. The results showed that nonexecutive members, chairman duty separation from CEO, number of board members, gender diversity and leverage have a negative relationship with firm performance. The results also showed that changes in board members, firm size and operation cash flow have a positive relationship with firm performance. Research results indicate that there is no significant relationship between institutional owners and firm performance.

Cost stickiness occurs due to disproportionate increase and decrease in the level of operating assets in periods of increase and decrease of demand and sales. Despite small changes in an activity, large changes in the activity, forces management to make changes in the cost structure of companies, which in turn, will lead to a change in the total cost. In addition, managers are more willing to change the cost in the time activities will be increased compared to when they will be decreased. This study considers and analyzes the sticky behavior of sales, general and administrative expenses (SG&A), cost of goods sold and total of SG&A expenses and cost of goods sold in Tehran Stock Exchange (TSE) for the period of 2004-2010. Moreover, the sticky costs behavior is analyzed for different levels of changes in sales revenues. Research hypothesis First main hypothesis: a relative magnitude of increase in costs when sales revenues increase is more than a relative magnitude of reduction in costs when sales revenues decrease. 1-1) a relative magnitude of increase in SG&A expenses when sales revenues increase is more than a relative magnitude of reduction in SG&A expenses when sales revenues decrease. 1-2) a relative magnitude of increase in costs of goods sold when sales revenues increase is more than a relative magnitude of reduction in costs of goods sold when sales revenues decrease. 1-3) a relative magnitude of increase in the total of costs of goods sold and SG&A expenses when sales revenues increase is more than a relative magnitude of reduction in the total of costs of goods sold and SG&A expenses when sales revenues decrease. Second main hypothesis: sticky behavior of costs is caused by large changes in volumes of sales revenues. 2-1) sticky behavior of SG&A expenses are caused by large changes in volumes of sales revenues. 2-2) sticky behavior of costs of goods sold is caused by large changes in volumes of sales revenues. 2-3) sticky behavior of the total of costs of goods sold and SG&A expenses is caused by large changes in volume of sales revenues. Model 1 Log Log * Log Where: DV = SG&A, CGS, or TOTAL (CGS + SG&A) For the second hypothesis, model 2 was exerted as follow: Model 2 Log log Where: DV = SG&A, CGS, or TOTAL (CGS + SG&A) R1it = 1 if percent change in sales revenue is [-0.1, 0.1] R2it = 1 if percent change in sales revenue is [-0.2, -0.1) or (0.1, 0.2] R3it = 1 if percent change in sales revenue is [-0.3, -0.2) or (0.2, 0.3] R4it = 1 if percent change in sales revenue is [-1, -0.3) or (0.3, 1] D1it = 1 if percent change in sales revenue is [-0.1, 0) D2it = 1 if percent change in sales revenue is [-0.2, -0.1) D3it = 1 if percent change in sales revenue is [-0.3, -0.2) D4it = 1 if percent change in sales revenue is [-1, -0.3) Conclusion and The findings of this research indicate that, there is a sticky behavior in SG&A expenses, cost of goods sold and their total. Also, the costs show a sticky behavior only when the following situations occur: 1) SG&A expenses are more than 30% change in sales revenues, 2) cost of goods sold is less than 10% and more than 30% change in sales revenues and 3) total of them for variation less than 20% and more than 30% in sales revenues. This is why the increased sales revenues more than 30% would lead managers to increase companies’ capacity. On the other hand, when sales revenues decrease more than 30%, managers are not willing or able to equally decrease the costs in their company. Therefore, this issue has caused the sticky behavior of costs including SG&A expenses, cost of goods sold and total of SG&A expenses and cost of goods sold, and shows sticky behavior for changes for more than 30% of sales revenues in all cases.

This research investigates the relation between overvaluing of equity and discretionary accruals. The statistical population was taken from listed companies in Tehran Stock Exchange, and sample of 86 listed companies was surveyed. High value of equity provides a strong incentive for managers to report earnings that do not disappoint the market. Jensen (2005) argued the overvalued firms can suffer from adverse consequences because of extreme valuation that encourages managers to act in ways that are detrimental to the long run value of their firms. For example when a firm becomes more overvalued, the pressure to meet increasingly unrealistic earnings targets becomes greater. We use two measures to identify overvalued firms: a) the price-earnings ratio and b) abnormal return. We stratify firms into three classes based on a procedure using both high prior-year P/E ratio and high prior-year abnormal return. Firms in highest class are classified as highly valued and are predicted to have higher future discretionary accruals. In summary, we hypothesize that an unusually high P/E ratio or unusually high prior-year abnormal return provides a manager with strong incentives to meet the implied market expectation for earning. Research hypotheses In this research we posit the following hypotheses, H1: Highly valued firms (firms with both high prior-year P/E ratio and high prior-year abnormal returns) will exhibit higher current year discretionary accruals levels relative to firms with lower valuations. H2: The inverse relationship between operating cash flow and discretionary accruals has higher R square for highly valued firms than firms with lower valuations. In this study we used three procedures for testing of hypothesis: a) Regression models, b) Independent- sample T- Test that compares means for two groups of cases and c) Bivariate Correlation that computes Pearson's correlation coefficient. The results of hypotheses test are represented as follows: First hypothesis has tested in two procedures: 1- Independent sample T-Test: results of comparing average discretionary accruals in highly valued firms and firms with low valuation indicate the average discretionary accrual is higher in highly valued firms than firms with low valuation; therefore, first hypothesis is accepted. 2- Application of regression models: Results of investigating of regression model indicate that the highly valuing variable is confirming. Second hypothesis has tested in two procedures too: 1- Bivariate correlation: in this procedure for testing of second hypothesis the Pearson correlation coefficient has been computed for two groups of firms and results indicate: a) the relation between operating cash flow and discretionary current accruals is inverse and b) quantity of this coefficient is more negative in highly valued firms than firm with low valuation but although the negative coefficients quantity indicates inverse relation in highly valued, it isn’t statistically significant at the 5% level; therefore, the second research hypothesis is not conforming. 2- The regression model: The results of investigating of model coefficients indicate although the negative coefficients quantity of interaction term HV*OCF indicates a strong inverse relation in highly valued, it isn’t statistically significant at the 5% level. Discussion and This paper provides evidence consistent with over valuation hypothesis that predicts that managers of highly valued firms have strong incentives to manage earnings up wards. The evidence suggests that high valuation increases the likelihood of earning management. Our results suggest that prices can drive accruals in contrast to the typical model where accruals drive price. One implication for directors is that they should be particularly conscious of potential earnings manipulation when their firms have extremely high valuation multiples.