درخت حوزه‌های تخصصی

The most common starting point for investors when buying a stock is to look at the trend of price changes. In recent years, different models have been used to predict stock prices by researchers, and since artificial intelligence techniques, including neural networks, genetic algorithms and fuzzy logic, have achieved successful re-sults in solving complex problems; in this regard, more exploitation Are. In this research, the prediction of stock prices of companies accepted in the Tehran Stock Exchange using artificial intelligence algorithm (non-sensory-parametric support vector regression algorithm in linear and nonlinear mode) has been investigated. The results of the research show that the PINSVR algorithm in nonlinear mode has been able to predict the stock price over the years, rather than linear mode.

Managers engage in income smoothing either to communicate private information about future earnings to investors (informativeness hypothesis) or to distort financial performance for opportunistic purposes (opportunism hypothesis). Business cycles and the monitoring role of institutional ownership may affect the earnings informativeness of income smoothing. The purpose of this research is to examine the effect of business cycles and institutional ownership on the earnings informativeness of income smoothing. 140 firms listed on the Tehran Stock Exchange are selected as the sample over the period 2010-2016. The results showed that, during recession, income smoothing does not effectively communicate information about future earnings and thus earnings are less informative. Moreover, higher levels of institutional ownership are associated with a decrease in their monitoring role and decrease in the earnings informativeness of income smoothing. Finally, the results suggested that the relationship between institutional ownership and the earnings informativeness of income smoothing is not significantly affected by business cycles.

One of the challenging issues for investors and professionals is appropriate models to evaluate financial situation of the firms. In this regard, many models have been extracted by researchers using different financial ratios to resolve these issues. However, choosing a model based on the conditions and users’ needs is complex. The main objective of this study is to identify the effect of contingency variables on the firms’ financial performance forecasting models. The statistical population of the research includes all firms listed in Tehran Stock Exchange during the period 2011-2018, among which 154 firms were selected. The research data were collected from firm's financial statements and other source. Multiple Discriminant Analysis and Logit Regression model were used to test the research hypotheses. According to the results of discriminant analysis, environmental uncertainty and firm size positively improve the predictive power of the firm's financial performance, and business strategy and business competition don’t improve the predictive power of the firm's financial performance. Also, the results of logit regression indicated that environmental uncertainty, business strategy, and firm size improve predictive power of the firm's financial performance; but, business competition don’t improve predictive power of the model. The results of comparing the two methods showed that the Discriminant analysis method outperformed the logistic regression method.

Hajj pilgrimage is one of the divine duties that is held every year by pilgrims. In addition to the jurisprudential issues of Hajj, the pilgrimage of Hajj has many individual, social, and political effects. This pilgrimage provides an opportunity for the pilgrims to gain spirituality. Anther role of Hajj is to create a platform for Muslims around the world to get to know each other. Professor Morteza Motahhari, as an Islamic thinker, believes that Hajj pilgrimage has great potentials for creating spirituality among Muslim societies. There is an international place (Kaaba) that belongs to all the believers of the world and also the same religious identity of the pilgrims of this holy house and some of the practices of this pilgrimage have the capacity to create real unity among Muslims. This research tries to study the role and position of Hajj pilgrimage in Professor Morteza Motahhari's thoughts by descriptive-analytical method and review the capacities of Hajj pilgrimage in creating spirituality from the perspective of Professor Morteza Motahhari.

Nowadays, the generated and shared content on tourist perceptions in social media is considered a fresh and far-reaching way to introduce the concept of the destination image. Destination decision-makers attempt to use this content to provide a deep understanding of tourism supply and demand. Marketers have to be particular about it when defining a proper destination image. In this regard, many researchers have emphasized the importance of using social media to tap into tourists’ perceptions of destination because it not only helps to deepen the administrators’ understanding of the demands of this type of tourism and to propose new approaches to determine the customers’ preferences in destination marketing but also directs new products and services to satisfy the tourists to a greater extent. Depending on the type of tourism, the contexts and criteria for this kind of virtual investigation are different. For example, in cultural destinations, tourists’ perceptions of tangible and intangible cultural heritage and services and products offered in virtual contexts are regarded as a tool to assess the tourists’ perceptions of that destination. The present study assumes that a holistic approach toward the analysis of tourist perception in the virtual sphere could be a well-qualified alternative to determine tourists’ wants in cultural destinations. Content analysis, which is a practical method in analyzing visual and textual data and  therefore is quite pertinent to the analysis of tourist perceptions, was adopted as the data analysis instrument in this study. To collect the data, two frequently-visited and widely-used websites with easy access to tourists’ comments, namely TripAdvisor and Flickr , were selected so that tourists’ experiences and perceptions could be gathered more authentically and conveniently. The findings demonstrated that the analysis of perceived authenticity of cultural destinations in Iran could provide the content required to create a destination image for purposeful marketing in Iran. Perceived Authenticity was categorized into three main themes: emotional, sensational, and rational.