حسن حیدری

Selecting approaches with appropriate accuracy and suitable speed for the purpose of making decision is one of the managers’ challenges. Also investing decision is one of the main decisions of managers and it can be referred to securities transaction in financial markets which is one of the investments approaches. When some assets and barriers of real world have been considered, optimization of stock basket can’t be solved easily, therefore, Meta-Heuristic approach is considered. In this regard, the main goal of this paper is to solve stock portfolio constrained optimization problem by using of Firefly Algorithm (FA) and Imperialist Competitive Algorithm (ICA). In order to do so, daily information of 25 accepted stocks in period of 2010-2016, in Tehran stock market have been used. Results show that Firefly Algorithm (FA) and Imperialist Competitive Algorithm (ICA) showed successful function in constrained optimization of stock portfolio and has acceptable accuracy in finding optimal answers in whole risk and returns levels. Also, the results of comparison of Cardinality Constrained Mean – Variance (CCMV) and Cardinality Constrained Mean – Semi -Variance (CCMSV) portfolios two using of Firefly Algorithm (FA) and Imperialist Competitive Algorithm (ICA) and considering to the findings of two criteria for assessing accuracy in stock basket optimization simultaneously show that Imperialist Competitive Algorithm (ICA) has high speed and accuracy for solving stock basket optimization and could have desirable interaction with real barriers of market. Moreover, there is high accuracy optimization of Cardinality Constrained Mean – Semi -Variance (CCMSV) compared to Cardinality Constrained Mean – Variance (CCMV).

Purpose: The aim of this study was to compare theory of Mind, IQ and attention of normal and hypothyroidism students. Materials & Methods: The research method was causal – comparative. The statistical society of it includes students studying in first-grade section of Saveh city that among them, 346 people were selected using random cluster sampling. In the first stage, 30 students were diagnosed with hypothyroidism by clinical examination and measurement of urinary iodine and 30 people were selected as healthful group (witness). In the second stage, the revised Wechsler Intelligence Scale for Children and the color-word Stroop test was performed to measure IQ, theory of mind and attention in both hypothyroidism and normal groups. Multivariate variance analysis, the mean and standard deviation were used to test the hypothesis. Findings: The results showed that there was a significant difference between theory of mind, the amount of IQ and attention of normal students with hypothyroidism students. The mean verbal and nonverbal and overall IQ of healthy group compared to hypothyroidism group was respectively 21.5 and 25 and 25.5 more .also, the theory of mind and attention in hypothyroidism group was reduced compared to normal group. Theory of mind, attention and IQ of hypothyroidism students was lower than normal students. Conclusion: in addition to intelligence, theory of mind and attention of hypothyroidism students was different from normal students.

Given the increasing importance of achieving low and stable inflation rate during the last decades, adopting the most suitable practices to implement monetary policies has always been of concern by monetary authorities of different countries. Inflation targeting (IT) regime is the most recent strategy to guide monetary policies that have been introduced following the occurrence of exchange rate targeting and monetary targeting problems. In this respect, in the present research, the performance of a number of IT countries versus that of the non-targeting ones was first investigated employing the difference in difference (DID) method. Then, considering monetary and oil shocks, IT performance in production gap in the economy of Iran was practically examined using smooth transition autoregressive regression (STAR) model. The Results indicated that implementation of IT policy was successful in applying the four main and most influential indicators in the production of treatment countries. In addition, it was revealed that variables such as IT, oil shock, and facility and exchange rates had a statistically negative effect on production shock in the economy of Iran. However, the monetary shock was found to have a statistically positive impact on production shock. Therefore, according to the findings regarding the successful performance of targeting countries, policymakers are recommended to implement IT policy during a long-term interval in order to stabilize it and also provide its prerequisites in the economy of Iran. JEL classification: E31, E58, E52.