مطالب

Purpose: Entrepreneurial leadership plays an effective role in improving the performance of various businesses including small and medium businesses. As a result, the current research was conducted with the aim of presenting a model of the role of entrepreneurial leadership in the performance of active small and medium businesses in the field of nanotechnology in Tehran. Methodology: The method of this research was of mixed exploratory type (qualitative and quantitative). The population of the present study in the qualitative section was the policy experts of the nanotechnology industry, which number of 17 of them were selected as a sample according to the principle of theoretical saturation and with the purposeful sampling method. Also, the population of present study in the quantitative section was the managers and experts of small and medium businesses of nanotechnology industry whit number 1434 people, which 303 people of them were selected as a sample according to Cochran's formula and with the available sampling method. The data of the qualitative and quantitative sections were collected with methods of semi-structured interview and researcher-made questionnaires, respectively which whose psychometric indicators were confirmed and analyzed with methods of thematic analysis in MAXQDA software and exploratory factor analysis and structural equation modeling in SPSS and LISREL software, respectively. Findings: The findings of the first part of current research showed that the model of the role of entrepreneurial leadership in the performance of active small and medium businesses in the field of nanotechnology had 13 sub-factors in the 5 main factors of guidance, support, coaching, facilitation and entrepreneurship. Also, the findings of the second part of the present study showed that the factor load, average variance extracted and reliability of all factors were appropriate. In addition, the model of the role of entrepreneurial leadership in the performance of small and medium-sized businesses active in the field of nanotechnology had a significant effect on all five main factors and each factor with its sub-factors (P<0.05). Also, the findings of the second part of the current research showed that the factor load, average variance extracted and reliability of all factors were appropriate. In addition, the model of the role of entrepreneurial leadership in the performance of active small and medium businesses in the field of nanotechnology had a significant effect on all five main factors and each main factor on its sub-factors (P<0.05). Conclusion: The model of the role of entrepreneurial leadership in the performance of active small and medium businesses in the field of nanotechnology has many practical implications for the activists in the field of nanotechnology industry, and they can according to the identified factors provide the basis for improving entrepreneurial leadership.

Volatility and risk measurement are essential parameters in risk management programs that can affect economic activities and public confidence in the stock market. Also, these two are the keys in the studies that connect the stock market, economic growth, and other financial factors. In recent years, due to the instability in the Tehran Stock Exchange, controlling the adverse effects caused by the volatility of stock prices, predicting and modeling price dynamics, and measuring risk have become necessary for the participants in this market. In the present research, the class of hidden Markovian index models of conditional variance Heteroskedasticity (HM-GARCH) is used to predict the volatility of stock prices and accounts of the Tehran Stock Exchange. For a comprehensive review, the models are selected to include the characteristics of volatility clustering, asymmetry in volatility (leverage effect), and heavy tail of stock returns (with t-student distribution). Based on RMSE and AME criteria, the HM-EGARCH-Normal Exponential GARCH model with normal distribution is more effective than other models in predicting stock market volatility. Therefore, leverage is necessary to analyze stock market risks using hidden Markov models, but heavy tail distribution is unnecessary. The results indicate that the HM-EGARCH-Normal model appropriately assesses volatility and improves market transparency and risk management forecasts. Also, the VaR and CVaR market risk assessment post-tests using Kupiec and DQ tests do not show evidence of overestimation or underestimation.

The rationality of religious belief systems indicates longitudinal relationships, so that each benefit from pertained rationality based on ontological place within the web of religious knowledge. Therefore, it can be possible to consider three layers of religious beliefs i.e. fundamental, middle, and marginal. Here fundamental beliefs are the most rational, followed by middle and finally marginal. Concerning Islamic and Christian traditions, there can be two beliefs, believing in one God and the hereafter, that are considered fundamental ones. There are also middle beliefs between the two mainstream religions that are about divine attributes, the relationship between God and human beings, and so on so forth. Finally, the level of marginal beliefs of two are about the sacredness of places, times, events, things, persons, situations etc. This research wants to show that although all religious beliefs have been expanded and changed under the influence of epistemic and non-epistemic factors, t fundamental beliefs have been more stable, immutable, universal, and compatible. Middle beliefs of Islam and Christianity, are generally based on believers’ plural understandings of religious texts and under aforementioned factors. Thus, in order to study the rationality of religions and their traditions, it is necessary to pay closer attention to how and under what conditions (epistemic and non-epistemic) their web of beliefs are formed and shaped.