Compound key word generation from document databases using a hierarchical clustering art model

The growing availability of databases on the information highways motivates the development of new processing tools able to deal with a heterogeneous and changing information environment. A highly desirable feature of data processing systems handling this type of information is the ability to automatically extract its own key words. In this paper we address the specific problem of creating semantic term associations from a text database. The proposed method uses a hierarchical model made up of Fuzzy Adaptive Resonance Theory (ART) neural networks. First, the system uses several Fuzzy ART modules to cluster isolated words into semantic classes, starting from the database raw text. Next, this knowledge is used together with coocurrence information to extract semantically meaningful term associations. These associations are asymmetric and one-to-many due to the polisemy phenomenon. The strength of the associations between words can be measured numerically. Besides this, they implicitly define a hierarchy between descriptors. The underlying algorithm is appropriate for employment on large databases. The operation of the system is illustrated on several real databases

How temporary is temporary employment in Spain?.

We use the Spanish Labor Force Survey (EPA) for the period 1987-1996 to study trends, characteristics, and labor force transitions of temporary workers. These are workers who hold fixed-term contracts, which the Spanish labor law distinguishes from indefinite contracts. Since the EPA questionnaire allows us to identify permanent from temporary workers, we are able to compare their characteristics. More importantly, we can use matched fIles from the same data source to analyze transitions from temporary to permanent employment. The aim is to test the extent to which temporary workers tend to be trapped in temporary employment relationships. Indeed, we fmd some evidence of this.Permanent and temporary employment; Fixed-term contract; Transition rate;

Trade policy and leapfrogging.

The recent extensive study of vertical product differentiation models has allowed for the analysis of international trade issues in the presence of country asymmetries in terms of product qualities, technology, cost, market size and income. In the presence of such asymmetries, national industries will either be market leaders or lagging behind in the international market place in terms of their product qualities. The resulting asymmetry in profits creates powerful incentives for lagging industries as well as their national Governments to reverse this situation to their advantage, i.e., to induce "leapfrogging" in terms of product qualities. This paper presents an overview of existing research on leapfrogging as well as several new results and questions.Product qualities; International trade; Trade policy;

Personalized Web Content with Fuzzy System

In this paper, we will develop a new computational intelligence methodology to automatically analyze and summarize web content during a user surfing sessions. The output of this process is meaningful keywords or phrases which will be used to bring the user other contents such as images that closely relate to the web pages that he or she is currently surfing

Equalizing opportunities through public education when innate abilities are unobservable

I consider the problem of equalizing opportunities among agents who differ in both their tastes and innate productive abilities when these characteristics are unobservable. The government specifically wishes to offset the effects of differences in innate talents by affording public education or training to those with lesser skills. I first show that in the benchmark case involving complete infonnation it is possible to fully equalize opportunities as defmed axiomatically by Bossert and Fleurbaey. Moreover, in the incomplete infonnation case, it is possible to implement any input progressive education policy by means of a direct implementation/revelation mechanism. However, it is not possible to afford equal opportunities. I conclude with an example demonstrating the alternative, social welfare function approach which I argue is more suitable for second-best analyses

How temporary is temporary employment in Spain?

We use the Spanish Labor Force Survey (EPA) for the period 1987-1996 to study trends, characteristics, and labor force transitions of temporary workers. These are workers who hold fixed-term contracts, which the Spanish labor law distinguishes from indefinite contracts. Since the EPA questionnaire allows us to identify permanent from temporary workers, we are able to compare their characteristics. More importantly, we can use matched fIles from the same data source to analyze transitions from temporary to permanent employment. The aim is to test the extent to which temporary workers tend to be trapped in temporary employment relationships. Indeed, we fmd some evidence of this

Trade policy and leapfrogging

The recent extensive study of vertical product differentiation models has allowed for the analysis of international trade issues in the presence of country asymmetries in terms of product qualities, technology, cost, market size and income. In the presence of such asymmetries, national industries will either be market leaders or lagging behind in the international market place in terms of their product qualities. The resulting asymmetry in profits creates powerful incentives for lagging industries as well as their national Governments to reverse this situation to their advantage, i.e., to induce "leapfrogging" in terms of product qualities. This paper presents an overview of existing research on leapfrogging as well as several new results and questions

Exploiting extensible background knowledge for clustering-based automatic keyphrase extraction

Keyphrases are single- or multi-word phrases that are used to describe the essential content of a document. Utilizing an external knowledge source such as WordNet is often used in keyphrase extraction methods to obtain relation information about terms and thus improves the result, but the drawback is that a sole knowledge source is often limited. This problem is identified as the coverage limitation problem. In this paper, we introduce SemCluster, a clustering-based unsupervised keyphrase extraction method that addresses the coverage limitation problem by using an extensible approach that integrates an internal ontology (i.e., WordNet) with other knowledge sources to gain a wider background knowledge. SemCluster is evaluated against three unsupervised methods, TextRank, ExpandRank, and KeyCluster, and under the F1-measure metric. The evaluation results demonstrate that SemCluster has better accuracy and computational efficiency and is more robust when dealing with documents from different domains

The asymptotic nucleolus of large monopolistic games

We study the asymptotic nucleolus of large differentiable monopolistic games. We show that if v is a monopolistic game which is a composition of a non-decreasing concave and differentiable function with a vector of measures, then v has an asymptotic nucleolus. We also provide an explicit formula for the asymptotic nucleolus of v and show that it coincides with the center of symmetry of the subset of the core of v in which all the monopolists obtain the same payoff. We apply this result to large monopolistic market games to obtain a relationship between the asymptotic nucleolus of the game and the competitive payoff distributions of the market