درخت حوزه‌های تخصصی

Examining the importance and influence of financial market companies is one of the main issues in the field of financial management because sometimes the collapse of a stock exchange company can affect an entire financial market. One systematic way to analyze the significance and impacts of companies is to use complex networks based on Interaction Graphs (IGs). There are different methods for quantifying the edge weight in an IG. In this method, the graph vertices represent the stock exchange companies that are connected by weighted edges (corresponding to the extent to which they relate to each other). In this paper, using the GARCH model (1,1) and the Clayton copula, we obtained the lower tail dependence interaction network of the first 52 companies of the Tehran Stock Exchange in terms of average market value, between June 2017 and October 2020. Then, based on the minimum spanning tree of the interaction network, we divided the companies into different communities. Using this classification, it was observed that the companies of the first group (Food Industry) and the second group (Oil Refinery) have the greatest impact on other companies. We also calculated the central indexes of the minimum spanning tree for each company. According to the results, the companies of the third group (Steel) have the highest average in the central indicators.

Designing the facade's color based on user evaluation is necessary due to the effect of color on people's evaluation. To evaluate the facade's color, its combination should be categorized. The emotional dimensions of color evaluation should be assessed due to the variety of emotional scales of color evaluation. Thus, the question arises: What are the emotional scales describing the facade's color and components. During a study, temperature, harmony, and weight were considered to describe the color in facades. This study used a combination of qualitative and quantitative methods to examine the components related to defining the color composition's weight scale. First, some components were identified to determine the weight of the color combination through a semi-structured interview. Based on the results, a questionnaire was prepared. The final results were obtained using the Q method analysis with the help of color strips and HSL codes. Therefore, to describe the combination color of the facade as light and heavy, the facade with a light color combination has at least 30% openings. At least 70% of facade areas and openings have a hue with more than 90% lightness. In addition, the saturation of at least 70% of the area is less than 30% and 5% with warm and cool hues, respectively. At least 70% of facade areas and openings have a hue with less than 65% lightness and a heavy color combination.

In a different context, the user's needs in a housing apartment are constantly changing; it is required that the provided house, by having flexibility, can always be responsive to the user's needs in various situations, which would be a challenge for specialized areas of housing, including design. To perform a flexible housing design, the architects face many different design solutions and variables, leading to confusion in this field. So, the objective of this study is to identify these variables and achieve an effective solution by considering their priority of them. The variables of this study were proposed in three scales of macro, medium, and micro according to the previous valid research studies in the field of flexible housing. Then, the variables have been evaluated using the specialist's idea through the Fuzzy Delphi method (FDM). The Friedman test has been used to analyze the data obtained from the questionnaires and achieve a valid ranking, which performs the ranking by calculating the mean rank for each variable. According to the results of data analysis, the characteristics of "spatial expansion and division," which means the possibility of space to be expanded (the expansion) or divided (the contraction), as the medium scale of housing design, has the greatest impact on the housing flexibility. On the macro scale, the "structure" component, and the micro-scale, the "use of flexible elements" provide the highest effectiveness in this regard. Moreover, as the medium scale, the modular design of space falls in the second place of influence compared to all other variables. Increasing the properties of spatial expansion and spatial division can be an effective design strategy for achieving flexibility in apartment housing. Also, modular space designing and flexible elements have been introduced as two solutions in the next priorities. All are considered small and medium scales and can be prioritized in designing flexible apartment housing.

Designing trading systems with good returns is critical for capital market investors. Trading systems are often based on a combination of several tools to use their combined information. For the first time in Iran, the present study aimed to propose a pattern detection algorithm for a flag pattern based on Japanese candlestick charts and their arrangement. By recognizing the pattern and if the 4- and 10-day moving average is confirmed, a shopping position is developed, and the selling time is determined based on an optimized and dynamic process commensurate with price changes and the data scale. Our objective was to address the question of whether the returns resulting from this strategy have a more significant positive return compared to the purchase and maintenance strategy. The research sample included the daily information of 16 active companies of basic metals in Tehran Stock Exchange during 2007-2019, extracted from the database of Novin Rahavard software. Data analysis was performed in MATLAB software, and the obtained experimental evidence was described using t-test. According to the results, the research strategy had a higher performance in terms of returns and risks compared to the market.

The issue of asset pricing in the market is one of the most important and old issues in the financial world. Factor pricing models seek to be able to determine a significant relationship between return on assets based on the risk parameters of that asset. A wide range of factors can be found in the literature that can be an element for measuring the risk of an asset, but the big question is which of these models will work better. The factors studied in this research include factors that cover market risk, valuation risk, psychological (technical) market risk, profit quality risk, profitability, investment, etc. In this study, we have tried to Using machine learning techniques and optimization tools is a way to derive adaptive-robust nonlinear models that can reduce the risk of model error as much as possible. In this research, two models have been developed. In the first model, using the feature extraction technique and optimization of models based on neural network, a non-linear and adaptable model has been developed for each asset. In the second approach, a portfolio of improved neural network-based models is used in the first stage, which can be used to minimize the risk of model error and achieve a model that is resistant to different market conditions. Finally, it can be seen that the development of these models can significantly improve the risk of error and average error of the model compared to traditional CAPM approaches and the Fama and French three-factor model.

Bank efficiency is essential in the establishment of healthy financial systems in countries. In this respect, bank managers are expected to respond correctly to questions raised about the financial performance of banks, which is practically impossible without examining the efficiency of the branches under their oversight. In most previous studies, Data Envelopment Analysis was used for evaluating the efficiency of financial branches. The large number of evaluation factors in the analysis leads to an increase in the number of efficient units and thus a decrease in the power of discrimination. Taking a systematic view into consideration, in this study, a step-by-step method was developed for selecting the effective factors in the efficiency of different branches of one of the Iranian Banks based on the effect of each factor or indicator on the whole system’s efficiency including the branches under evaluation. To this end, a new method was proposed for the evaluation of system’s efficiency and some of its properties were stated.