Maximum Likelihood Inference for Log-linear Models Subject to Constraints of Double Monotone Dependence

To model an hypothesis of double monotone dependence between two ordinal categorical variables A and B usually a set of symmetric odds ratios defined on the joint probability function is subject to linear inequality constraints. Conversely in this paper two sets of asymmetric odds ratios defined, respectively, on the conditional distributions of A given B and on the conditional distributions of B given A are subject to linear inequality constraints. If the joint probabilities are parameterized by a saturated log-linear model, these constraints are nonlinear inequality constraints on the log-linear parameters. The problem here considered is a non-standard one both for the presence of nonlinear inequality constraints and for the fact that the number of these constraints is greater than the number of the parameters of the saturated log-linear model.This work has been supported by the COFIN 2002 project, references 2002133957_002, 2002133957_004. Preliminary findings have been presented at SIS (Società Italiana di Statistica) Annual Meeting, Bari, 2004.     

Territorial Impact Assessment for European regions: A methodological proposal and an application to EU transport policy

The need to engage European research and institutions in the new field of Territorial Impact Assessment, from both a methodological and a procedural perspective, was stated some years ago by the European Spatial Development Perspective (ESDP). The necessity of multidimensional evaluation of the likely impact of policies and programmes on the territory – understood as the dimension on which all the other relevant dimensions (economic, social, environmental and cultural) converge and with which they integrate – emerged as a natural consequence of the importance of spatial aspects in the future development of the Union and of widespread preoccupations about certain emerging spatial trends.A proposal for a TIA methodology combining logical consistency vis-à-vis the Union's present institutional and policy guidelines with operational viability is being developed and applied to Trans-European Networks policy of the EU. Territorial impact is linked to an innovative definition of the objective of “territorial cohesion” of the Treaties in terms of territorial efficiency, quality and identity.Utilising sectoral impact studies developed inside the ESPON programme and developing territorial indicators for impact, vulnerability and desirability (territorial utility functions), a multicriteria model (TEQUILA) is implemented on priority projects as defined by the Commission, and results mapped and described for the 1360 NUTS-3 regions of the Union.     

A general algorithm to fit constrained DEDICOM models

The DEDICOM model is a model to analyze square tables describing asymmetric relationships among n entities. Its importance in the asymmetric multidimensional scaling literature is due to the fact that several authors showed a large class of models to be simply a constrained version of DEDICOM. A typical example is the Generalized GIPSCAL proposed by Kiers & Takane. In this paper we present a new algorithm capable to fit, in the least squares sense, any DEDICOM constrained model.     

Modelling two way contingency tables with recursive logits and odds ratios

In this work a new type of logits and odds ratios, which includes as special cases the continuation and the reverse-continuation logits and odds ratios, are defined. We prove that these logits and odds ratios define a parameterization of the joint probabilities of a two way contingency table. The problem of testing equality and inequality constraints on these logits and odds ratios is examined with particular regard to two new hypotheses of monotone dependence. Work partially supported by a MIUR2004 grant. Preliminary findings have been presented at SIS (Società Italiana di Statistica) Annual Meeting, Torino, 2006.     

Predicting Severity of Foreign Body Injuries in Children in Upper Airways: An Approach Based on Regression Trees

The entry of a small item into the upper airways is one of the leading causes of injuries in children up to 14 years old. The aim of this study is to characterize types of objects causing choking along with the features of the children involved in the accident and compare results with current standards. The European Survey on Foreign Bodies Injuries Study (ESFBI) collected data on foreign body injuries from 19 European countries. The data from ESFBI were selected according to the ICD-9-CM codes 933 (foreign body in the pharynx and larynx) and 934 (foreign body in the trachea, bronchi, and lungs). Both a classification tree and a linear discriminant analysis (LDA) have been set up to predict the probability that an injured child experiences a hospitalization. The classification tree provides flowchart-type decision rules and allows for analyzing the impact of the item features, the children characteristics, and the circumstances of the accidents on the severity of the foreign body injuries. Results showed that children younger than 3.5 who are involved in an accident have a high probability to experience a hospitalization.     

The policies of unemployment protection in Europe

The abundant literature on welfare state policies, regimes or ‘worlds’ has been only limitedly interested in unemployment protection, and even less in youth unemployment protection. What is clearly lacking in the literature is an updated analysis of the most recent policies developed in European countries targeting youth. This mini‐symposium aims to fill in this gap by presenting findings from an EU‐funded research project entitled ‘Youth, Unemployment and Exclusion in Europe: A Multidimensional Approach to Understanding the Conditions and Prospects for Social and Political Integration of Young Unemployed’ (YOUNEX). The main aim of the research endeavour was to develop theory and contribute to empirical knowledge concerning the social and political exclusion of unemployed youth in Europe.