درخت حوزه‌های تخصصی

Recently, understanding the anomalies in financial markets have severely chal-lenged the efficient market hypothesis (EMH). The price momentum is one of the anomalies described as the unexplained short-term return by Fama and French (1996). The present research strives for modeling the price momentum of winner stock in the Iranian capital market. The grounded theory method was used to explain this phenomenon. To this end, in-depth interviews were held with 32 experts operating in the professional and academic fields in 2018. The collected data was encoded in three steps, and the results were presented as a conceptual paradigm. The research findings identified the momentum causal factors in the behavioral level, the background factors in the social, macroeconomics, and mar-ket levels, the intervening factors in the global economics, macroeconomics, mar-ket, and company levels, and the strategies in the social, macroeconomics, market, the investment and finances institutions, and consequences factors in market level. The research findings suggest that the winner stock price momentum phenomenon should not be considered a speculation opportunity. Rather, it is an anomaly that has to be regulated with the proposed strategies according to the experts. The consequences of the adoption of these strategies include the stable and normal income for the market actors, the decrease in the loss inflicted on natural persons due to the market volatility, the management of anomalies, more effective attrac-tion and allocation of liquid capitals, the reduced credit risk of brokerages, and the acceleration of liquidation in the market.

Having adequate, sufficient and timely information and data is very important for investors' decision making. Processing information and allocating the asset are two fundamental tasks in the securities market and the stock price is more likely to have the nature of disclosure, information effectiveness and asset allocation efficiency. Thus, in this research, the effects of large block transactions and ownership nature on the non- financial disclosure have been investigated in the corporates accepted in Tehran Stock Exchange. Research population involves the corporates accepted in Tehran Stock Exchange for a 5-year period (2010-2014) that according to research constraints and using the systematic deletion method, the data related to 133 corporates were gathered. In this study, five main hypotheses have been suggested. To analyze the desired data and test the research hypotheses, the software of Eviews has been implemented. Results indicated that the number of large block transactions and nature of ownership are effective in non-financial information disclosure at the whole and the corporates with high transactions, those with low transactions, those in a business group and those in a diverse business group but the effect and explanatory of dependent variables by the independent ones vary at each level.