Iranian Journal of Finance

In this research, we use a pair trading strategy to make a profit in an emerging market. This is a statistical arbitrage strategy used for similar assets with dissimilar valuations. In the present study, smooth transition heteroskedastic models are used with the second-order logistic function for producing thresholds as trading entry and exit signals. For generating upper and lower bounds, we apply the rolling window approach and one-step-ahead quantile forecasting. Markov chain Monte Carlo sampling method is used for optimizing the parameters. Also, passive strategy in the out-of-sample period is used to compare the profits. The population consists of 36 daily stock returns in Tehran Stock Exchange. Then, we select ten pairs from these stocks and use Minimum Square Distance method, and five pairs from one industrial sector. Finally, we see strategy1 and 2 have positive returns in the out-of-sample period, and they produce higher returns than passive strategy.

Working capital should be available to any company to have the sufficient funds to cover short-term commitments and operating costs in the future. This guarantees the continuity of the company’s activities. Given the significance of the role of working capital management (WCM) in the companies, the study analyzed the content of texts and studies done in this field, presented three main hypotheses and examined the effect of most of the variables affecting WCM (both external and internal factors of the company), as well as the consequences of WCM in 161 companies listed in Tehran Stock Exchange (TSE) during a seven-year period from 2011 to 2017. The purpose of the study was to determine the most important factor affecting WCM and its consequences. The hypotheses were tested using multivariate regression and Granger causality test. The hypothesis testing indicated that extra-organizational factors such as gross domestic product (GDP), inflation rate and exchange rate have the greatest effect on WCM. Moreover, hypothesis testing indicated that some intra-organizational factors, such as current ratio, capital expenditures, financial leverage, return on assets, operating cycle, operating profit return, institutional shareholders ownership-percentage, and independence of board of directors affect WCM. Finally, hypothesis testing showed that optimal capital management improves the firms’ performance.

Based on the capital market’s nature, accountants and auditors’ information is provided by an effective influence of personal decisions and market results, derived systematically by information structure and market participants’ features. Auditors’ choices are influenced by perception, judgment and decision options processes, which may affect auditing errors. The study purpose is to investigate auditors’ different biases and decision-making factors on errors based on a cognitive approach in the capital market. The model’s objective is practical based on a descriptive-analytical methodology. The statistical population of the study includes all certified auditors of Iran's Securities and Exchange Organization (SEO), whom were provided with the researcher-made questionnaires with valid narration and reliability. The collected data were analyzed by AMOS software. The findings indicate that components of the cognitive bias are predictable by auditors’ errors based on the priority level and maximum influences, including mental accounting bias (63%), availability bias (45%), heuristic bias (60%), and ambiguity aversion bias (58%). Also, components of decision-making are predictable by auditors’ errors based on the priority level and maximum influences, including decision case (54%), job experience (57%), decision-making situation (58%) and individual features (45%).

The evaluation of corporate social responsibility has gained significance over the past decade due to the importance of natural and environmental resources. Many studies have been conducted on corporate social responsibility and the presented related models, which add to the importance of this report. However, in addition to its significance, many researchers also believe that corporate social responsibility evaluation models lack the necessary efficiency due to different interpretations, lack of transparency, and abuse of some companies in order to deceive and commit fraud. Therefore, the aim of this research is to present a model to evaluate corporate social responsibility using value added, which can be a suitable criterion in evaluating the social responsibility of commercial entities. In the present study, first, a model was developed based on corporate social responsibility, and then, to test the model, social value added of Nano motor oil was studied as a case study. In this study, data was analyzed through pairwise comparison. The findings of the study conducted on the social value added of Nano motor-oil indicate economic efficiency of 40%, product social efficiency of 8%, and depicts a 38-times increase in social value added compared with its economic added value. Thus, Nano-engine oil producing companies are located on the corporate social responsible category and the corporate social responsibility in this product is on the third level (strong) that indicates the product’s efficiency in the community and can be a suitable incentive for all business organizations to pay more attention to their products’ environmental and social impacts.

Governments always affect the economic environment as legislators in the field of business. The economic conditions governing the market and business require different conditions and contexts for decision making and corporate execution practices. Companies and managers administering them under environmental conditions, achieve their goals by employing various earnings management methods. Hence, the present study examines the effect of governments’ economic performance on the earnings management methods used in listed companies of Tehran Stock Exchange (2004-2016) for a sample of 16 industries and 271 companies. To test the hypotheses, multivariate regression model was used. The results showed that during the research period, companies managed earnings, and while more than 70% of companies used the accrual earnings management method, there was a relationship between annual economic indicators and real earnings management, and the change in general level of prices and the political connections of states have affected the relationship. Also, the accruals-based earnings management method occurred independent of annual economic indicators and there is a significant relationship between governments changes and earnings management methods.

The purpose of this paper is to examine the asymmetric effects of banking sector and stock market development on economic growth in Iran. For this purpose, Smooth Transition Regression (STR) model used based on seasonal time series data during 1989-2017. The results indicate that the impact of financial and banking development indices on economic growth is different for economic growth rates above and below 6%. Therefore, if the economic growth rate is higher than 6%, then we have a regression and when economic growth is lower than 6% will have another regression in order to effect of financial development of economic growth. In addition, results show that that the relationship between private sector credit and economic growth is much stronger than the relationship between stock market and economic growth.