On the generalized negative binomial distribution

The generalized negative binomial distribution (GNBD) was defined and studied by Jain and Consul (1971). The GNBD model has been found useful in many fields such as random walk, queuing theory, branching processes and polymerization reaction in chemistry. In this paper, four methods by which the GNBD model gets generated are discussed. The different methods of estimating the model parameters are provided. By using the bias property, we found that the truncated version of GNBD model provides a better parameter estimates than the GNBD model when fitted to data sets from the GNBD model.     

Self-touching and attentional processes: The role of task difficulty,selection stage,and sex differences

Lateral and bilateral self-touching movements were studied in a group of men and women performing a series of attentional tasks. In all tasks, subjects were instructed to selectively attend to, and shadow (i.e., repeat outloud), one of two passages that were presented simultaneously through earphones. Loudness, voice quality, or thematic content determined which passage had to be selected and shadowed. Performance was significantly better when shadowing on the basis of loudness or voice quality (an earlier, easier selection) than when following content (a more difficult selection that occurs at a later stage in the information processing continuum). However, self-touching rates during performance were not simply a function of task difficulty but seemed to depend on the processing stage at which selection occurred as well as on the type of selection involved. Strong, significant associations emerged between lateral self-touching and performance measures in most of the tasks for the women but in only one task for the men. The sample size on which these correlations are based is small and, hence, these findings must be interpreted with caution. However, in the light of previous findings on sex differences with these tasks, the present results suggest that lateral movements may serve different functions in men and women.We are grateful to Dr. Norbert Freedman, Director of the Unit at which this work was carried out, for his encouragement and support during all phases of this project, and to Dr. Marshall Bush for generously making available to us his selective listening tasks. Some findings reported in this paper were included in the second author's master's thesis at New York University, Department of Psychology.     

Book reviews

Franco Ferrarotti The Myth of Inevitable Progress, Greenwood Press, 1985, pp.VIII,208.

Peter Grootings, Bjorn Gustavsen, and Lajos Héthy (eds.) New Forms of Work Organization and Their Social and Economic Development, Budapest, Statistical Publishing House, 1986, pp. VIII, 297.

Janusz Lewandowski and Jan Szomberg Samorzad w dobie “Solidarnosci”. Wspolpraca samorzadow pracowniczych Pomorza Gdanskiego na tle sytuacji w kraju w latach 1980/81 (Self‐government in the time of Solidarity. Cooperation of the self‐governmental bodies in the Baltic region and its general background during the period 1980/81), London, Odnowa, 1985, pp. 109.     

Approximate versus Exact Equilibria in Dynamic Economies

This paper develops theoretical foundations for an error analysis of approximate equilibria in dynamic stochastic general equilibrium models with heterogeneous agents and incomplete financial markets. While there are several algorithms that compute prices and allocations for which agents' first‐order conditions are approximately satisfied (“approximate equilibria”), there are few results on how to interpret the errors in these candidate solutions and how to relate the computed allocations and prices to exact equilibrium allocations and prices. We give a simple example to illustrate that approximate equilibria might be very far from exact equilibria. We then interpret approximate equilibria as equilibria for close‐by economies; that is, for economies with close‐by individual endowments and preferences. We present an error analysis for two models that are commonly used in applications, an overlapping generations (OLG) model with stochastic production and an asset pricing model with infinitely lived agents. We provide sufficient conditions that ensure that approximate equilibria are close to exact equilibria of close‐by economies. Numerical examples illustrate the analysis.     

Global supplier development considering risk factors using fuzzy extended AHP-based approach

Global supplier development is a multi-criterion decision problem which includes both qualitative and quantitative factors. The global supplier selection problem is more complex than domestic one and it needs more critical analysis. The aim of this paper is to identify and discuss some of the important and critical decision criteria including risk factors for the development of an efficient system for global supplier selection. Fuzzy extended analytic hierarchy process (FEAHP) based methodology will be discussed to tackle the different decision criteria like cost, quality, service performance and supplier's profile including the risk factors involved in the selection of global supplier in the current business scenario. FEAHP is an efficient tool to handle the fuzziness of the data involved in deciding the preferences of different decision variables. The linguistic level of comparisons produced by the customers and experts for each comparison are tapped in the form triangular fuzzy numbers to construct fuzzy pair-wise comparison matrices. The implementation of the system is demonstrated by a problem having four stages of hierarchy which contains different criteria and attributes at wider perspective. The proposed model can provide not only a framework for the organization to select the global supplier but also has the capability to deploy the organization's strategy to its supplier.     

Social Capital, Satisfaction and Quality of Life in the Workplace

This article is an empirical analysis of the relationship between social capital and satisfaction and quality of life in the workplace in Spain. Social capital has been defined as the set of cooperative relationships between social actors that facilitate collective action. This concept has been measured based on five dimensions: trust, social relations, commitment, communication and influence. An analysis has been carried out applying regression and causal models to determine the influence on satisfaction and quality of life at work of social capital dimensions and of characteristics of the worker, work environment and company or organization. The data is based on Spain's 2001 Quality of Life at Work Survey. The results of the analysis indicate that the models applied are significant, which confirms the examined propositions. Higher levels of social capital imply greater levels of satisfaction and quality of life at work. Social capital is a better predictor of quality of life at work and job satisfaction than the characteristics of the worker, the company or organization, and the work environment.