An Adjustable Fuzzy Chance-Constrained Network DEA Approach with Application to Ranking Investment Firms

This paper presents a novel approach for performance appraisal and ranking of decision-making units (DMUs) with two-stage network structure in the presence of imprecise and vague data. In order to achieve this goal, two-stage data envelopment analysis (DEA) model, adjustable possibilistic programming (APP), and chance-constrained programming (CCP) are applied to propose the new fuzzy network data envelopment analysis (FNDEA) approach. The main advantages of the proposed FNDEA approach can be summarized as follows: linearity of the proposed FNDEA models, unique efficiency decomposing under ambiguity, capability to extending for other network structures. Moreover, FNDEA approach can be applied for ranking of two-stage DMUs under fuzzy environment in three stages: 1) solving the proposed FNDEA model for all optimistic-pessimistic viewpoints and confidence levels, 2) then plotting the results and drawing the surface of all efficiency scores, 3) and finally calculate the volume of the three-dimensional shape in below the efficiency surface. This volume can be as ranking criterion. Remarkably, the presented fuzzy network DEA approach is implemented for performance appraisal and ranking of investment firms (IFs) with two-stage processes including operational and portfolio management process. Illustrative results of the real-life case study show that the proposed approach is effective and practically very useful

Fuzzy Data Envelopment Analysis Approach for Ranking of Stocks with an Application to Tehran Stock Exchange

The main goal of this paper is to propose a new approach for efficiency measurement and ranking of stocks. Data envelopment analysis (DEA) is one of the popular and applicable techniques that can be used to reach this goal. However, there are always concerns about negative data and uncertainty in financial markets. Since the classical DEA models cannot deal with negative and imprecise values, in this paper, possibilistic range directional measure (PRDM) model is proposed to measure the efficiencies of stocks in the presence of negative data and uncertainty with input/output parameters. Using the data from insurance industry, this model is also implemented for a real case study of Tehran stock exchange (TSE) in order to analyse the performance of the proposed method

An epidemiological survey of psychiatric disorders in Iran

BACKGROUND: The nation-wide epidemiological survey of psychiatric disorders in term of lifetime prevalence is not adequately known in Iran. The prevalence of lifetime psychiatric disorders was estimated among the population of aged 18 and over on gender, age group, educational level, occupational status, marital status, and residential area. METHODS: The subjects were 25,180 individuals selected through a clustered random sampling method. The psychiatric disorders were diagnosed on the bases of Diagnostic and Statistical Manual of Mental Disorders-IV criteria. It is the first study in which the structured psychiatric interview administered to a representative sample of the Iranian population age 18 and over by the 250 trained clinical psychologist interviewers. The data was entered through EPI-Info software twice in an attempt to prevent any errors and SPSS-11 statistical software was also used for analyses. The odds ratios and their confidence intervals estimated by using logistic regression. RESULTS AND DISCUSSION: The prevalence of psychiatric disorders was 10.81%. It was more common among females than males (14.34% vs. 7.34%, P < 0.001). The prevalence of anxiety and mood disorders were 8.35% and 4.29% respectively. The prevalence of psychotic disorders was 0.89%; neuro-cognitive disorders, 2.78% and dissociative disorders, 0.77%. Among mood disorders, major depressive disorder (2.98%) and among anxiety disorders, phobic disorder (2.05%) had the higher prevalence. The prevalence of psychiatric disorders among divorced and separated 22.31%; residents of urban areas 11.77%; illiterates 13.80%; householders 15.48%; unemployed 12.33% that were more than other groups. CONCLUSION: The mental health pattern in Iran is similar to the western countries, but it seems that the prevalence of psychiatric disorders in Iran may be lower than these countries. It is estimated that at least about 7 millions of Iranian population suffer from one or more of the psychiatric disorders. It shows the importance of the role of the psychiatric disorders in providing preventive and management programs in Iran

Sociological approach to the Social movement of Blacks in America (Analysis of Origins, processes and outcomes)

Introduction Social movements are the type of the protest collective behavior that have emerged in modern societies. These movements organized a collective endeavor of significant part of the population that aims to change the thought, behavior and social relationships. Black movement in North America a prime example of this type of movement. More than a century African-American by providing any political opportunity in America, protested and strive to achieve equal rights with whites. This campaign, especially from the 1960s, has produced a lot of ups and downs in relations the black community with the government of this country. A recent example is the killing of 18-year-old Michael Brown of black America by police in Ferguson that prompted the massive response and public anger of black America against the policy of racial discrimination of the country's sovereignty. Accordingly, the main question of this study is that: what’s the causes and motives of revitalization and protests over the past few years in the community of black America? In response to this question, based on resource mobilization theory (the framework and structure of political opportunity) this hypothesis put to the test that: the black movement As a result of convergence the individual objectives and goals of the movement and existence of discontents and grievances such as racism, institutionalized discrimination and unequal and weak social and economic status of blacks in American society and also creating political opportunities such as the Civil Rights Act, Voting Rights Act, election and increasing the number of black officials "have been activated and thereby provided the groundwork for collective action is.     Materials and Methods Research method of this article is qualitative (causal explanation type), based on documentary sources and secondary data. To explanation the issue, the resource mobilization theory which includes the framework and political opportunity theory is used. Traditionally, this theory regarded social movements as political actors and knows them the continuation of political organizations such as political parties and groups the pressure. Theory of Structures of "political opportunity" that lies within a tradition of resource mobilization theory, more to the point, how resources mobilized by social movements for solving social discontents. Political opportunity theory, emphasis on the presence or absence of political opportunities. McAdams believes that the form of mobilization and it’s time is influenced by the perceived political opportunities. People through "framework" define dissatisfaction, build collective identity and to create, interpret and transform opportunities for social movements. Social movements by linking individual perceptions with the perceptions of the movement throughout the process that Snow calls it "rallying framework" trying to attract and activate its fans and followers. Of Framework-building theory of Snow is used to describe and analyze why the movement activate and how the frameworks, marked dissatisfaction for members. And how the movements with interpretation of issues, situations, events and emphasize on unbearable social conditions of some of its members, mobilizing their followers. Discussion of Results and Conclusions  In sum, based on the results of the article, the political and social conditions of the blacks in America society and also political-economic structures is the main factor for the black movement. To be precise, Inequality in wealth and quality of life is the main dissatisfaction of the blacks. According to the latest statistics, about 12 percent of America's total population are blacks. While about 31.9 percent of total arrests in this country are blacks. Segregation in the economy has been expanding in 2011 and at the beginning of the economic crisis, 1.91 percent of African - Americans and 91.5 percent of Latinos- Americans were homeowners. Rules in America interpreted by black people judges and police in such a way that traces of segregation evident on it. Published reports suggest that the New York police in 2011 has stopped 700,000 persons that 85 percent of them were African-American. The result of such discrimination is institutionalized violence against ethnic minorities. Differences in socio-economic status, including differences in the distribution of wealth, income and access to resources is negatively affected the individuals of society. Class divisions in America, a financial burden caused by successive wars continued and costly to taxpayers, led to the socioeconomic inequalities in society and eventually lead to racial discrimination is America. From the view point of this research, in the last few years, the arrival of a black president and the formation of the Occupy Wall Street movement, political-needed opportunity to keep the black movement has created. At these events the black movement in America, with the definition and interpretation of the events could encouraged their supporters to collective action against ruled policies. The existence of racial, judicial and economic discrimination have produced long-term incentives and events such as Ferguson has provided short-term motives of expansion of the black movement in America. Therefore, the blacks community of America have used every political opportunity to protesting   the discrimination against blacks in America were trying to transform and change in thought, behavior, social relationships ,causing changes in power relations of the society and state

A Novel Robust Network Data Envelopment Analysis Approach for Performance Assessment of Mutual Funds under Uncertainty

Mutual fund (MF) is one of the applicable and popular tools in investment market. The aim of this paper is to propose an approach for performance evaluation of mutual fund by considering internal structure and financial data uncertainty. To reach this goal, the robust network data envelopment analysis (RNDEA) is presented for extended two-stage structure. In the RNDEA method, leader-follower (non-cooperative game) and robust optimization approaches are applied in order to modeling network data envelopment analysis (NDEA) and dealing with uncertainty, respectively. The proposed RNDEA approach is implemented for performance assessment of 15 mutual funds. Illustrative results show that presented method is applicable and effective for performance evaluation and ranking of MFs in the presence of uncertain data. Also, the results reveal that the discriminatory power of robust NDEA approach is more than the discriminatory power of deterministic NDEA models

A new strategic approach for R&D project portfolio selection using efficiency-uncertainty maps

Purpose: New business practices and the globalization of markets force firms to take innovation as the fundamental pillar of their competitive strategy. Research and Development (R&D) plays a vital role in innovation. As technology advances and product life cycles become shorter, firms rely on R&D as a strategy to invigorate innovation. R&D project portfolio selection is a complex and challenging task. Despite the management\u27s efforts to implement the best project portfolio selection practices, many projects continue to fail or miss their target. The problem is that selecting R&D projects requires a deep understanding of strategic vision and technical capabilities. However, many decision-makers lack technological insight or strategic vision. This article aims to provide a method to capitalize on the expertise of R&D professionals to assist managers in making informed and effective decisions. It also provides a framework for aligning the portfolio of R&D projects with the organizational vision and mission. Design/methodology/approach: This article proposes a new strategic approach for R&D project portfolio selection using efficiency-uncertainty maps. Findings: The proposed strategy plane helps decision-makers align R&D project portfolios with their strategies to combine a strategic view and numerical analysis in this research. The proposed strategy plane consists of four areas: Exploitation Zone, Challenge Zone, Desperation Zone and Discretion Zone. Mapping the project into this strategic plane would help decision-makers align their project portfolio according to the corporate perspectives. Originality/value: The new approach combines the efficiency and uncertainty dimensions in portfolio selection into an integrated framework that: (i) provides a complete representation of the stochastic decision-making processes, (ii) models the endogenous uncertainty inherent in the project selection process and (iii) proposes a computationally practical and visually unique solution procedure for classifying desirable and undesirable R&D projects

A novel two-phase robust portfolio selection and optimization approach under uncertainty: A case study of Tehran stock exchange.

Portfolio construction is one of the most critical problems in financial markets. In this paper, a new two-phase robust portfolio selection and optimization approach is proposed to deal with the uncertainty of the data, increasing the robustness of investment process against uncertainty, decreasing computational complexity, and comprehensive assessments of stocks from different financial aspects and criteria are provided. In the first phase of this approach, all candidate stocks' efficiency is measured using a robust data envelopment analysis (RDEA) method. Then in the second phase, by applying robust mean-semi variance-liquidity (RMSVL) and robust mean-absolute deviation-liquidity (RMADL) models, the amount of investment in each qualified stock is determined. Finally, the proposed approach is implemented in a real case study of the Tehran stock exchange (TSE). Additionally, a sensitivity analysis of all robust models of this study is examined. Illustrative results show that the proposed approach is effective for portfolio selection and optimization in the presence of uncertain data

A novel fuzzy data envelopment analysis based on robust possibilistic programming: possibility, necessity and credibility-based approaches

Possibilistic programming approach is one of the most popular methods used to cope with epistemic uncertainty in optimization models. In this paper, several robust fuzzy data envelopment analysis (RFDEA) models are proposed by the use of different fuzzy measures including possibility, necessity and credibility measures. Despite the regular fuzzy DEA methods, the proposed models are able to endogenously adjust the confidence level of each constraints and produce both conservative and non-conservative methods based on various fuzzy measures. The developed RFDEA models are then linearized and numerically compared to regular fuzzy DEA models. Illustrative results in all of the FDEA and RFDEA models show that, maximum efficiency is obtained for possibility, credibility and necessity-based models, respectively

Examining the effect of Knowledge Management factors on Mobile Learning adoption through the use of Importance-Performance Map Analysis (IPMA)

A tremendous amount of research indicated that KM factors have significant impacts on different technologies at the organizational level. What is not yet clear is the influence of these factors on technology adoption at the individual level. On the other hand, the understanding of students’ behavioral intention to use m-learning systems is still an ongoing research issue. Thus, the main theoretical contribution of this study is to investigate the impact of KM factors (i.e., acquisition, sharing, application, and protection) on m-learning adoption at the individual level, and to identify the importance and performance of each factor using the importance-performance map analysis (IPMA) technique through SmartPLS. A total of 319 IT undergraduate students enrolled at Al Buraimi University College in Oman took part in the study by the medium of online survey. In terms of importance, the empirical data analysis through IPMA exhibited that knowledge protection is the most important factor in determining the students’ behavioral intention to use m-learning. Concerning performance, the findings also triggered out that both knowledge sharing and knowledge protection perform well in determining the students’ behavioral intention to use m-learning