مجید زنجیردار

The purpose of this study is to identify the effect of stock tendency to deal with fluctuations and price fluctuation thresholds in creating fluctuations. The statistical population of the present study is the companies listed on the Tehran Stock Exchange that were present in the stock exchange during the years 2005 to 2018. In order to confirm and reject the research hypothesis, Eviews software has been used. In Tehran Stock Exchange, following severe stock price fluctuations, the stock price fluctuation mechanism is used to limit severe stock price fluctuations, and according to certain periods, the range of stock price fluctuations changes and over time the range of fluctuations increases. The basis of trial and error has been determined and in a short period of time there have been many changes in the procedures related to the application of stock price fluctuations, without really measuring the impact of these decisions in the market and investors' reaction to changes in price fluctuations. Findings showed that the number of times each share hits the price fluctuation Yield fluctuation has a significant effect.slow efficiency fluctuations have a significant effect; And in line with the concepts of hyper-reactive theory, it can be justified, that is, after the price reaches the range of fluctuation, the trend reverses and the basis of the fluctuation limit changes; It has changed the volatility of stock returns based on jump and price continuity.

Due to the existence of various paradigms and theories in accounting and various methods introduced to measure accounting values, as well as the lack of a complete and well-defined framework of these theories in terms of sociological paradigms, we decided to analyze sociology from theories. To achieve this goal, we used the content analysis method. In this way, first by examining the schools and theories of sociology and the main paradigm of positivism, interpretiveness, identification and components that were the characteristics of these paradigms were extracted and categorized from the themes and then the outputs were approved by sociology professors. And then accounting measurement theories and various theories using the method of taking notes from books and texts and articles extracted and sociological components in the context of accounting theories are searched and analyzed and at the end of accounting theories according to The extracted themes and their analytical codes are classified and analyzed and interpreted based on the obtained results. The results of the analysis of themes, new theories of accounting measurement tend to interpretism in which the role of the accountant is more prominent and historical cost theory is classified as a positivist sociological theory.

FinTech is the solution that strengthens the way of financial communication and if we apply this technology, it will provide us with new methods of performing smarter, more agile and wider financial services. The purpose of this study is to investigate and analyze the factors affecting the implementation of FinTech in Iran's banking industry using structural equation modeling to provide comprehensive solutions of removing barriers and development of this industry in the Iranian banking industry by fully understanding the current situation. The present article is of descriptive-analytical type and data collection has been done through library studies and questionnaires. The statistical sample of the study was 12147 personnel working in Iran's banks in 1400. Due to the size of the population, Cochran’s method and random sampling method were used to determine the sample size. To analyze and classify the extracted data, a questionnaire and a test of the main hypothesis and sub-hypotheses and structural equation modeling were used using smart PLS statistical software. The obtained results confirm the main hypothesis and the sub-hypotheses of the research. The results indicated that in the banking sector, there is a need for legalization and harmonization with upstream laws, as well as the need for infrastructure and tools that are very important in adopting strategies to implement FinTech in Iran's banking industry, in order to make transparency, reduce costs, provide high-speed services, and move towards a smart economy.

The purpose of this study is to perform a meta-analysis of the relationship between auditor characteristics and profit quality. In order to integrate the results of different researches and identify the factors that modulate the relationships between auditor characteristics and profit quality, in this research we will use meta-analysis methodology which is one of the quantitative statistical methods. In order to implement the meta-analysis method, they were identified and collected from the websites of foreign journals (articles published in the period 2005 to 2020) and the Internet site of domestic scientific research journals (articles published during the years 2006 to 2021) as a statistical population of the research. Systematic removal has finally analyzed 50 studies; The results of studies conducted in the period and around this relationship indicate that most of these studies are heterogeneous. In order to identify the cause of this heterogeneity, by dividing the research based on different criteria for measuring profit quality and auditor characteristics and calculating intra-group chi-square statistics, we found that these different measurement criteria used in research are one of the factors of contradiction in the results. There have been researches. In the following study, it was observed that there is no significant relationship between auditor characteristics with profit smoothing and timely profit and also between non-audit services provided by the auditor and profit quality, while in contrast, there is no significant relationship between auditor characteristics and quality of accruals; Profit stability; There is the ability to predict profit and conservatism.

This study aimed to evaluate the effect of peer performance, future competitive performance and factors of correlation with peer companies on the manipulation of abnormal real operations. The research subjects included listed companies in Tehran Stock Exchange during 2013-2017. In total, 128 companies were selected as the statistical sample using systematic elimination approach. Peer performance, future competitive performance, and factors of correlation with peer companies were independent variables of the research, whereas the manipulation of abnormal real operations was the dependent variable. This was an applied research in terms of use and a correlational study regarding methodology. Data were collected using the library method, and explanatory notes, financial statements, and monthly journal of stock exchange were considered in the data section. Moreover, descrip-tive and inferential statistics were exploited to describe and summarize the col-lected data. Furthermore, data analysis was performed using variance heterogene-ity tests, F-Limer, Hausman, and Jarque and Bera tests, followed by the applica-tion of the multiple regression test for confirming or rejecting the research hy-potheses (Eviews Software). According to the results of the study, peer perform-ance, future competitive performance, and factors of correlation with peer compa-nies affected the manipulation of abnormal real operations.

Finding the best way to optimize the portfolio after Markowitz's 1952 article has always been and will continue to be one of the concerns of activists in the investment management industry. Researchers have come up with different solutions to overcome this problem. The introduction of mathematical models and meta-heuristic models is one of the activities that has influenced portfolio optimization in recent decades. Along with the growing use of portfolios and despite its rich literature, there are still many unanswered issues and questions in this area. Also, Iranian capital markets, as emerging markets, require native research to answer these questions and issues. The purpose of this study is to provide a useful and effective tool to assist professionals and researchers in portfolio selection theory. This study, while comprehensively reviewing the literature on the subject and the developments and expansions made in the area of portfolio selection and optimization, reviews the types of problems and optimization methods.