Debt management in a small open economy: A theoretical and an empirical study for Belgium

This article analyzes the effects of debt management and its consequence for the control of base money in a small open economy (Belgium). The study compares the effects obtained from a small theoretical model with the results of a larger empirical model.The theoretical model focuses on the financing of government by money operation, on the bond rate, and on the international reserve of the Central Bank.The empirical model is a medium-term one, including the demand and the supply sectors of the economy and permitting simultaneous analysis of real and financial variables.The effects of an endogeneous or exogenous debt management have been studied by numerical simulation of modification in the public expenditure, the world trade, and the discount rate.     

EXCESS DEMAND AND MARKET ADJUSTMENT

This paper develops a model of wage and price adjustment that is based on the optimizing behavior of firms. The output of the model is a relationship between price changes and excess demands that looks like a generalized Walrasian adjustment but which is based on firm microfoundations. The model is then applied to stability analysis and the "Phillips curve," using restrictions derived from the underlying optimization to generate results.     

Problem Behavior and Heart Rate Reactivity in Adopted Adolescents: Longitudinal and Concurrent Relations

The present longitudinal study examined resting heart rate and heart rate variability and reactivity to a stressful gambling task in adopted adolescents with aggressive, delinquent, or internalizing behavior problems and adopted adolescents without behavior problems (total N=151). Early‐onset delinquent adolescents showed heart rate hyporeactivity to the stress‐eliciting gambling task compared to late‐onset delinquent adolescents and adolescents without behavior problems. Heart rate, heart rate variability, and reactivity to stress were not related to environmental factors such as early‐childhood parental sensitivity, parental socioeconomic status, or adoptee's health status at arrival. We conclude that the distinction between delinquency and aggression and between childhood‐onset and adolescence‐onset delinquency is important for the study of stress reactivity in adolescents.     

A Bayesian model for ranking hazardous road sites

Summary.  Road safety has recently become a major concern in most modern societies. The identification of sites that are more dangerous than others (black spots) can help in better scheduling road safety policies. This paper proposes a methodology for ranking sites according to their level of hazard. The model is innovative in at least two respects. Firstly, it makes use of all relevant information per accident location, including the total number of accidents and the number of fatalities, as well as the number of slight and serious injuries. Secondly, the model includes the use of a cost function to rank the sites with respect to their total expected cost to society. Bayesian estimation for the model via a Markov chain Monte Carlo approach is proposed. Accident data from 519 intersections in Leuven (Belgium) are used to illustrate the methodology proposed. Furthermore, different cost functions are used to show the effect of the proposed method on the use of different costs per type of injury.     

Testing the demand-control-support model among health-care professionals: A structural equation model

This paper reports a further empirical validation of the Demand-Control-Support Model (DCS model), which was developed by Johnson and colleagues (1988, 1989). Data were collected from a heterogeneous group of health-care professionals (nurses and nurses' aides; n = 249). Three major refinements were made to the validation of the DCS Model. First, all relationships in the model were estimated simultaneously by means of covariance structure modelling (LISREL 8). Second, the control dimension was refined substantially, using a psychometrically more sound assessment of the workers' autonomy. Third, the model was applied to the work of health-care professionals. The data did not confirm the assumption that both job strain and motivation are multiplicative functions of job demands, autonomy and social support. First, the results suggested that high levels of autonomy attenuate the increase of emotional exhaustion due to job demands. These results partially supported Karasek's Job Demand-Control Model (Karasek 1979). Second, high levels of social support proved to attenuate the increase of emotional exhaustion due to autonomy. Finally, the main effect of autonomy on job challenge implied that an increase in autonomy is accompanied by an increase in job challenge (and, consequently, job involvement). In addition, low job demands and a high amount of work-related support seem to reduce feelings of exhaustion and, consequently, health complaints.     

Simplicial Pivoting Algorithms for a Tractable Class of Integer Programs

We present a tractable class of integer feasibility problems. This class of max-closed IP problems was studied in somewhat restricted form by Glover, Pnueli, Hochbaum and Chandrasekaran and has a logic counterpart known as the class of Horn formulas. First we modify the existing algorithms in order to avoid the related recognition problem. Then we show that in order to solve these max-closed IP problems, simplicial path following methods can be used. This is important because these methods are flexible with respect to starting conditions, which make them more suitable than the top-down truncation algorithms that have been suggested.     

The EFOM 12C energy supply model within the EC modelling system

This article describes the EC-EFOM 12C model in general and refers where possible to existing documentation. It also reports on the first completed experimental case study and on planned future analysis. This model was developed in one of the research programs undertaken by the European Commission aimed primarily at multinational studies. Data are obtained from research carried out by an interactive network of national implementation teams working with a central group at the Commission. The energy system used is an oriented network carrying the primary energy over intermediate stages till finally meeting consumers' demand. The numerical information, constituting the attributes that characterise the various energy transformation processes, is stored in the European energy data base. About 225 transformation processes distributed over 17 subsystems characterised for six time periods up till 2020 for all EC countries are involved. The management of the data base is performed by an interactive software and this data base is designed for use in simulation studies and for linear programming optimisation with various objective functions. The model has been used in a parallel case study to explore substitution possibilities between an investment policy reducing the primary energy imports and one where these investments are restrained at the cost of having to import more primary energy. Results are shown and briefly discussed. Finally the relationship of this EFOM 12C model with the other EC models developed in the same research subprogram is outlined.     

Maintaining strategic momentum: The CEO''s agenda

How does the chief executive of a large complex organization maintain strategic momentum? This represents a great challenge when there are no obvious external threats, and no obvious reasons for having a concerted action. Floris Maljers, Charles Baden-Fuller and Frans van den Bosch explore the inherent tensions which exist between stability and change. Change is necessary to maintain success, but too much change is disastrous. The authors argue that there are several possible solutions to this paradox, including that of generating periods of intense activity followed by periods of comparative stability and incremental improvement. Using the introspection of one of the CEOs of Unilever, who held office from 1984 to 1994, the authors examine how these tensions were played out and resolved.