درخت حوزه‌های تخصصی

Since the seismic behavior of the earth’s energy (which follows from the power law distribution) can be similarly seen in the energy realized by the stock markets, in this paper we consider a statistical study for comparing the financial crises and the earthquakes. For this end, the TP statistic, proposed by Pisarenko and et al. (2004), is employed for estimating the critical point or the lower threshold, i.e. the point beyond that the market energy follows from the power law (Pareto) distribution. The results confirm the deviation of the energy from the Pareto distribution in the high quantiles of the energy data. The upper threshold that the energy's distribution is changed from the Pareto to another distribution is also estimated by TP statistic. A simulation study is employed for checking out the statistical behavior of the estimated thresholds. Finally, the magnitude of the financial earthquakes is studied. The results indicate that the domestic and the international events have caused the financial earthquakes in Tehran Stock Exchange. Also, the positive relation between the daily energy released and the daily magnitude of the shocks that was connected by Gutenberg and Richter (1956) is confirmed.

Supply chain integration represents the extent based on which a producer strategically cooperates with its supply chain partners and collaboratively manages inter-organizational and intra-organizational processes. The current research has been conducted to examine the effect of supply chain integration on operational efficiency and value creation. In order to do this, Annan’s et al. (2016) standard questionnaire was used to measure the research variables. The research method was descriptive correlational. In order to answer the research questions and investigate the research hypotheses, structural equations and path analysis by means of the partial least squares method (PLS) were used with Smart-PLS software. The obtained results indicate that there is a positive and significant relationship between the inter-firm networking resources and dysfunctional competitions on the supply-chain integration. The results also approve the positive and significant effect of supply chain integration on customer value creation and the company’s operational efficiency.

Performance appraisal is a process which help shareholders make informed and optimal investment decisions. In recent decades, a long stream of research has devoted particular attention to the importance and impact of financial decisions on firm performance and firm value. The present study thus is primarily concerned with investigating the association between free cash flow and institutional ownership and long-term performance of the firms listed on the Tehran Stock Exchange over the period of 2012-2016. Moreover, firm size, financial leverage and sale grows serve as the control variables of the research. A number of 89 firms listed on the Tehran Stock Exchange were selected, and then the research hypotheses were tested using multivariate regression model based on panel data. The results reveal that firm long-term performance is not significantly correlated with free cash flow, yet it has a significant relationship with institutional ownership.

Assessment of writing skill is generally believed to be judged by a rater subjectively and qualitatively or by using analytic scoring rubrics which can potentially result in somehow not very reliable assessment. It seems that an evaluation of writing based on a model can result in a valid and reliable writing assessment. To achieve such an objective, this study firstly aimed to develop an assessment model based on Activity Theory (AT), i. e., Activity Theory-Based Assessment Model (ATBAM), and then to employ it in the assessment of writing performances of Iranian language learners in a private language college. And finally, to achieve the concurrent validity of ATBAM, its results were compared with those of a traditional approach. Three groups of participants took part in this study: a group of upper intermediate English learners (N=29) who submitted one writing sample per week in four successive weeks, teachers (N=6) who provided learners with feedback and assigned holistic scores and course supervisors (N=2) who reassessed the writing samples on the basis of an analytic rubric of writing assessment. The results showed that using ATBAM in writing assessment results in an exploration of not only learners’ but also teachers’ engagement in the development of learners’ writing ability. The role of teachers’ feedback and teachers’ and learners’ social interaction in the development of learners’ writing ability could potentially provide comprehensive, fair, reliable, and valid scores in this model.

The marriage between technology and teaching in educational milieus in recent years has been a major concern among educational researchers in general and applied linguists in particular as far as augmented reality (AR) and virtual reality (VR) are concerned. Augmented reality after virtual reality received much attention over the last decades in mobile assisted language learning context. AR mixes virtual world onto real environment, VR delve the participants in to the virtual world. To examine the effect of AR and VR on abstract writing of EFL students, 12 intermediate proficiency pairs (high and low proficiency) participated based on their scores on TOEFL and a hypothetical abstract writing task. The participants were required to write an abstract according to the sub-moves of Hyland's (2000) move analysis provided through three mobile applications including AR-, VR HeadSet virtual reality-, and paper-based scaffoldings for four weeks in a collaborative context. In evaluating the groups' abstract writing scores before and after the treatment, no significant differences were found among the three groups. However, the AR group revealed better mean average results ( M = 33) compared to the other VR ( M = 24) and paper-based groups ( M = 29). Besides, the low intermediate proficiency subjects in the AR group received higher scores ( M = 40) compared to heir higher counterpart ( M = 37). Results imply that the integration of real and unreal worlds might be a good asset in teaching the genre of abstracts to EFL learners in general and low intermediate proficiency learners in particular.