فصلنامه بررسی های حسابداری و حسابرسی
پیاپی 61 (پاییز 1389)

Regarding the critical role of liquidity in asset price discovery, sharing of financial risk and transaction costs reduction, it is important to know about the effective factors. This study offers evidences about the role of institutional ownership in the stock liquidity. In this research, for separating various impacts of institutional ownership, we used two measures as institutional ownership level and concentration. The level of institutional ownership is the proxy of trading and monitoring activity and the concentration of such ownership is the proxy of adverse selection and free float share reduction. We defined 15 different trading and information liquidity measures. Considering sampling limitations, we examined 138 corporations, from 1384 to 1388. We utilized linear multivariable regression to test our research hypothesis. The results indicate that liquidity is positively related to institutional ownership level; but institutional ownership concentration has a significant negative effect on stock liquidity. The finding is true about both trading measures including trading volume, free float share percentage and Amihud measure and also information measures like bid-ask spread.

This study investigates the relationship between Auditor Quality and Accrual Reliability. To determinate of auditor quality, using two metrics of Auditor Size and Auditor Tenure, and following Richardson, we use accrual persistence for measure of accrual reliability. In this study, we investigated the listed companies in Tehran stock exchange, over the period of 1380-1386. For testing hypothesis, the multiple linear regression and measurement method of Cross-sectional are used. We find evidence that reported accruals audited by higher-quality audit firms have a more persistence coefficients compared to reported accruals of companies audited by lower-quality audit firms, and finally have a more accrual reliability.

To improve in understanding audit quality, multiple researches were performed to obtain a better understanding for this concept to determine the relationship between audit quality and other variables. One of the variables which its relationship with audit quality was reviewed in many research, is auditor size. One of the first researches in this respect was performed by De Angelo in 1981. In his studies, he concluded that there is a positive relationship between audit quality and auditor size. In the present research, the researchers seek to study the relationship between audit quality and auditor size in Iran. In this study, Iranian certified public audit firms as small audits and audit organization, due to having many personnel and oldness, is considered the big audit. To study the quality, researchers, criterion, the comparison of discovered and reported misstatements in audit reports are performed by separating it into five kinds of misstatements by comparing the current year audit report and statement of retained earning in the future year. The method used is dichotomy research and the statistical analyses performed in this research indicate a meaningful and inverse relationship between audit quality and auditor size.

One of the capital market anomalies and exceptions in finance are momentum. Momentum strategies are applied to use serial correlation available in market and securities returns. In these strategies investors can earn excess return as follow: buying winner stocks in the past and selling loser stocks in the past. In this study, we are going to explore the profitability of price and earning momentum strategies in Tehran Stock Exchange. Also, the impact of factors such as abnormal return, standardized unexpected earnings, price to earnings per share ratio, book value to market value ratio and company’s size on return of these strategies are investigated 1383 to 1387. This research based on four hypothesizes which most important of these hypothesizes is: by using price and earning momentum strategies in Tehran Stock Exchange, an investor can earn excess return. Results indicate that price momentum strategy in 3-month, 6-month and one-year time periods in Tehran stock exchange is profitable. However, earnings momentum strategy only in 3-month and 6-month time horizons is profitable. Testing third hypothesis show that in 3-month and 6-month time horizons, the model’s independent variables justify the excess return of price momentum strategy but in one-year time period, except for independent variables, other factors affect the excess return. In forth hypothesis, significant relationship between price and earnings momentum strategies in 3-month and 6-month time horizons is accepted but in one-year period, there is no significant relation between them.