Showing papers by "Tilburg University published in 1994"

Organizational Learning and diversification

Abstract: Employing concepts of lateral and longitudinal learning, we examined the dissolution of 462 expansions of Dutch firms, both acquisitions and new ventures. We interpreted the endurance of an expansi...

Transfer in Bilingual Development: The Linguistic Interdependence Hypothesis Revisited

Abstract: This study aimed to find empirical evidence for the linguistic interdependence hypothesis, which states that in bilingual development, language and literacy skills can be transferred from one language to another. Ninety-eight 6-year-old Turkish children, living in the Netherlands since infancy, were selected prior to their entrance into the first grade of primary school. A longitudinal design monitored the development of lexical, morphosyntactic, pragmatic, phonological, and literacy abilities in the children's first and second languages. To minimize test-bias, I developed linguistic tasks, which required minimal instruction, analyzing interdependence relationships in bilingual development with LISREL techniques. The results clearly show that at the level of lexicon and syntax, language transfer was quite limited. At the level of pragmatic skills, phonological skills, and literacy skills, however, positive evidence appeared for the interdependence in bilingual development.

Central effects of baroreceptor activation in humans: Attenuation of skeletal reflexes and pain perception

Abstract: Activating the arterial baroreceptors blunts pain sensation and produces other forms of central nervous system inhibition in animals. These effects may be important to blood pressure regulation but have not been rigorously verified in humans. We describe (i) a noninvasive behaviorally unbiased method for baroreceptor stimulation and (ii) the application of this method to measurement of baroreceptor-mediated attenuation of pain perception and of the Achilles tendon reflex. The findings are relevant to basic mechanisms of blood pressure stabilization and cardiovascular reactivity and may also have implications for noncompliance with antihypertensive medications and for the pathophysiology of essential hypertension.

Asymmetrical cross-language priming effects

Abstract: Three experiments were conducted to examine cross-language priming in bilinguals. The first was a cross-language primed lexical decision task experiment with Chinese-English bilinguals. Subjects made lexical decisions about primary associate targets in the two languages at the same rate, but priming occurred only when the prime was in their first language (L1), Chinese, and the target was in their second language (L2), English. Experiment 2 produced the same pattern of asymmetrical priming with two alphabetic languages, French and Dutch. In Experiment 3, the crucial stimuli were translation equivalents. In contrast to the results of Experiments 1 and 2, priming occurred across languages in both the L1-L2 and L2-L1 conditions. However, this priming was also asymmetrical, with more priming occurring in the L1-L2 condition. A tentative separate-interconnected model of bilingual memory is described. It suggests that the representations of words expressed in different languages are stored in separate memory systems, which may be interconnected via one-to-one links between some translation-equivalent representations as well as meaning-integration processes.

Environmental tax reform and endogenous growth

Abstract: This paper explores the effects of an environmental tax reform on pollution, economic growth and welfare in an endogenous growth model with pre-existing tax distortions. We find that a shift in the tax mix away from output towards pollution may raise economic growth through two channels. The first channel is an environmental production externality, which determines the positive effect of lower aggregate pollution on the productivity of capital. The second channel is a shift in the tax burden away from the net return on investment towards profits. The paper also shows that, if tax shifting towards profits is large and environmental amenities are unimportant, the optimal tax on pollution may exceed its Pigovian level.

Domain‐specific Market Segmentation

Abstract: Proposes domain‐specific market segmentation as a promising approach as compared with segmentation based on general or on brand‐specific variables. Treats product differentiation and positioning as the counterpart of market segmentation. The link between market segmentation, on the one hand, and product differentiation, on the other hand, is the product benefit. The product benefit is the interaction of the product and the consumer.

What Macroeconomists Should Know about Unit Roots: A Bayesian Perspective

Abstract: This paper summarizes recent Bayesian research on unit roots for the applied macroeconomist in the way Campbell and Perron [8] summarized the classical unit roots perspective. The appropriate choice of a prior is discussed. In recognizing a consensus distaste for explosive roots, I find the popular Normal-Wishart priors centered at the unit root to be reasonable provided they are modified by concentrating the prior mass for the time trend coefficient toward zero as the largest root approaches unit from below. I discuss that the tails of the predictive density can be sensitive to the prior treatment of explosive roots. Because the focus of an investigation often is on a particular persistence property or medium-term forecasting property of the data, I conclude that Bayesian methods often deliver natural answers to macroeconomic questions.

Modeling lexical borrowability

Abstract: In this article, we develop analytical techniques to determine borrowability – that is, the ease with which a lexical item or a category of lexical items can be borrowed. The analysis is based on two assumptions: (1) the distribution of items in both the host and donor language should be taken into account to explain why certain items are, and others are not, borrowed; (2) the borrowability of a lexical category may result from a set of (underlying) operative factors or constraints. Our analysis is applied to Spanish borrowings in Bolivian Quechua on the basis of a set of bilingual texts.

The acquisition of stress: a data-oriented approach

Abstract: A data-oriented (empiricist) alternative to the currently pervasive (nativist) Principles and Parameters approach to the acquisition of stress assignment is investigated. A similarity-based algorithm, viz. an augmented version of Instance-Based Learning is used to learn the system of main stress assignment in Dutch. In this nontrivial task a comprehensive lexicon of Dutch monomorphemes is used instead of the idealized and highly simplified description of the empirical data used in previous approaches.It is demonstrated that a similarity-based learning method is effective in learning the complex stress system of Dutch. The task is accomplished without the a priori knowledge assumed to pre-exist in the learner in a Principles and Parameters framework.A comparison of the system's behavior with a consensus linguistic analysis (in the framework of Metrical Phonology) shows that ease of learning correlates with decreasing degrees of markedness of metrcal phenomena. It is also shown that the learning algorithm captures subregularities within the stress system of Dutch that cannot be described without going beyond some of the theoretical assumptions of metrical phonology.

A spatiotemporal dipole model of the Stimulus Preceding Negativity (SPN) prior to feedback stimuli

Abstract: Ten subjects performed a time production task, in which they were instructed to press a button four seconds after the presentation of an auditory stimulus. Two seconds after the button press they received either auditory or visual feedback on the temporal accuracy of their response. In such a paradigm negative slow brain potentials can be recorded preceding the response (Movement Preceding Negativity, MPN) as well as preceding the feedback stimulus (Stimulus Preceding Negativity, SPN). Spatiotemporal dipole modelling is used to gain insight in the possible generators of MPN and SPN. From the models it follows that the MPN can be described by one contralateral radial dipole and a bilateral pair of tangential dipoles. All three dipoles are located near central electrode positions, so the generators of the MPN probably reside within the motor cortex. The SPN is modelled by a bilateral frontotemporal pair of dipoles, hypothetically representing activation of the Insulae Reili. The insular cortex is involved in the processing of affective-motivational input, such as carried by the feedback in the present paradigm. However, processing of the information content of the feedback stimulus might by itself also activate the frontal cortex. Both the response and the feedback stimulus are followed by a positive peak, which can be described by the same deep posterior dipole. Both peaks probably represent a P3, which is related to context updating.

Monotonicity and stability of periodic polling models

Abstract: This paper deals with the stability of periodic polling models with a mixture of service policies. Customers arrive according to independent Poisson processes. The service times and the switchover times are independent with general distributions. The necessary and sufficient condition for the stability of such polling systems is established. The proof is based on the stochastic monotonicity of the state process at the polling instants. The stability of only a subset of the queues is also analyzed and, in case of heavy traffic, the order of explosion of the queues is given. The results are valid for a model with set-up times, and also when there is a local priority rule at the queues.

Is a stimulus conveying task‐relevant information a sufficient condition to elicit a stimulus‐preceding negativity?

Abstract: Movement-preceding and stimulus-preceding negativities were recorded when a movement was followed by one of three informative visual stimuli. The meaning of the visual stimulus alternated between (a) conveying a task-relevant instruction about a subsequent time production task and (b) providing feedback (knowledge of results) about performance on the current time production task. In a control condition, premovement and postmovement scalp potentials were recorded when subjects made the same movements but in a voluntary, self-paced manner. Under all conditions, movements were preceded by a movement-preceding negativity, and neither the amplitude nor the lateral asymmetry of this negativity was affected by the subsequent presentation of either kind of informative stimulus. When the movement was followed by a stimulus conveying knowledge of results, the negativity in the postmovement epoch was enhanced, but this enhancement was not evident in epochs preceding instruction stimuli. We conclude that not all task relevant stimuli elicit a stimulus-preceding negativity, and we provide a functional interpretation of this negativity in terms of emotional anticipation and the contingency of the stimulus on a previous event.

Simply Logical: Intelligent Reasoning by Example

Abstract: From the Publisher: An introduction to Prolog programming for artificial intelligence covering both basic and advanced AI material A unique advantage to this work is the combination of AI, Prolog and Logic Each technique is accompanied by a program implementing it Seeks to simplify the basic concepts of logic programming Contains exercises and authentic examples to help facilitate the understanding of difficult concepts

The discrete-time Riccati equation related to the H/sub /spl infin// control problem

Abstract: The H/sub /spl infin// control problem has been solved recently with the use of discrete-time algebraic Riccati equations. In this paper, we investigate this Riccati equation. We derive recursive methods to find the stabilizing solution of this Riccati equation. Moreover, we derive several properties of the class of positive semi-definite solutions of this equation. >

Do Autistics Have a Generalized Face Processing Deficit

Abstract: The study presents results from a clinical test battery (Bruyer & Schweich, 1991; Schweich & Bruyer, 1993) that is used to study components in the face recognition system of autistic children. The results of the autisties are compared with the performance of two age groups of normal children (7-10 years, 12-16 years) and an adult control group. Autistic subjects, like young children, make more errors on a task in which they have to match facial features in the context of a complete face but not when the features are presented in isolation or in a simplified facial context. Finally, the sensitivity of the battery for clinical populations other than prosopagnosics is discussed.

Optimal Environmental Taxation in the Presence of Other Taxes: General Equilibrium Analyses

Abstract: This paper examines the optimal setting of environmental taxes in economies where other, distortionary taxes are present. We employ analytical and numerical models to explore the degree to which, in a second best economy, optimal environmental tax rates differ from the rates implied by the Pigovian principle (according to which the optimal tax rate equals the marginal environmental damages). Both models indicate, contrary to what several analysts have suggested, that the optimal tax rate on emissions of a given pollutant is generally less than the rate supported by the Pigovian principle. Moreover, the optimal rate is lower the larger are the distortions posed by ordinary taxes. Numerical results indicate that previous studies may have seriously overstated the size of the optimal carbon tax by disregarding pre-existing taxes.

The measurement of household cost functions: revealed preference versus subjective measures.

Abstract: Since the work of Pollak and Wales (1979), it is well-known that demand data are insufficient to identify a household cost function. Hence additional information is required. For that purpose I propose to employ direct measurement of feelings of well-being, elicited in surveys.

A univariate analysis of EMS exchange rates using a target zone model

Abstract: SUMMARY The models in the literature on exchange-rate target zones imply a non-linear time series model for the exchange rate. We show how the parameters of such models can be estimated and develop Maximum Likelihood and Method of Simulated Moments estimators for the target zone model of Krugman (1991). The Maximum Likelihood estimator is based on a computationally attractive approximation to the exact predictive density of the continuous time model. Monte Carlo experiments are used to assess the properties of this estimator. In the empirical part we estimate the model with data on recent EMS exchange rates. We find that the Krugman (1991) target zone model is not able to explain the full observed kurtosis and conditional heteroscedasticity of the exchange-rate returns.

Measuring the complexity of writing systems

Abstract: We propose a quantitative operationalisation of the complexity of a writing system. This complexity, also referred to as orthographic depth, plays a crucial role in psycholinguistic modelling of reading aloud (and learning to read aloud) in several languages. The complexity of a writing system is expressed by two measures, viz. that of the complexity of letter‐phoneme alignment and that of the complexity of grapheme‐phoneme correspondences. We present the alignment problem and the correspondence problem as tasks to three different data‐oriented learning algorithms, and submit them to English, French and Dutch learning and testing material. Generalisation performance metrics are used to propose for each corpus a two‐dimensional writing system complexity value.

Daily Bundesbank and federal reserve interventions: Are they a reaction to changes in the level and volatility of the DM/$-rate?

Abstract: This paper reports on the results of an empirical investigation into the objectives of daily foreign exchange market intervention by the Deutsche Bundesbank and the Federal Reserve System in the U.S. dollar-Deutsche Mark market. Tobit analysis is implemented to estimate the intervention reaction functions consistently. It is found that an increase in the conditional variance in daily exchange rate returns derived from a GARCH model estimated in the paper, led the Bundesbank and the Federal Reserve to increase the volume of intervention, both in case of dollar-sales and purchases on account of their leaning against the wind policy.