Showing papers by "Tilburg University published in 1980"

What is wrong with legs in motor preparation

Abstract: Publisher Summary This chapter discusses the wrong with legs in motor preparation The results of experiment I are confirmed by those of experiment II A systematic error is unlikely, particularly with regard to the results of exp III, in which contralateral larger amplitudes are found, in line with the literature The same set-up is used in all 3 experiments It could be hypothesized that a tonic activating influence is present in the left hemisphere, as always the same response is made, causing a negative DC shift Because of a ceiling effect it might be that the amplitude increase related to the movement itself could become less pronounced in the contralateral hemisphere than in the ipsilateral one However, the same holds for the uncued motor responses with the finger, where contralaterally, larger amplitudes have been found A different control mechanism for finger and foot responses also might be of importance However, although dominance for hand movements is much more pronounced than for foot movements, it still remains unclear why the ipsilateral hemisphere should show an opposite picture instead of a lack of difference between both hemispheres

Regression Estimation in Simulation

Abstract: In simulation an input variable like interarrival time is sampled, and hence its average deviates from its known expectation. This information can be used to improve the estimated simulation response: regression sampling or control variate technique. The usual crude estimator is shown to be biased. If local linearity holds, then the regression estimator becomes unbiased. Moreover its variance becomes smaller under mild conditions. The assumption of local linearity is an alternative to the normality assumption of other authors. This paper further emphasizes the difference between results ex ante (unconditional) and ex post (given the experimental input values). A telephone-exchange simulation provides a case study.

23 Motor Preparation, Recorded on the Cortical and Spinal Level

Abstract: EEG and Hoffmann reflexes were recorded during the four sec foreperiod of two reaction time experiments. Subjects responded with a plantar flexion of either their right or left foot. Preceding right foot movements larger CNV amplitudes were found over the right hemisphere. With left foot movements amplitudes also were larger over the right hemisphere, but the difference in amplitude between both hemispheres was much smaller than with right foot responses. The time course of changes in reflex amplitudes gave no indication of a selective element in the preparatory process. A hypothesis is presented about the relation between changes on the cortical and spinal level during motor preparation.

On economics and technical change

Abstract: The article is divided into four sections. The first consists of a review of a few main lines of Heertje's thoughts on the relation between economics and technical change. It appears that Dr. Heertje has chosen to write a basically non-mathematical book dealing with the history of technology, production theories and the significance of technical development for economic growth, monopoly power and economic policy. The general comments in the second section make it clear that his study is an excellent survey of the literature on the subject. It covers an overwhelmingly large number of topics and includes copious notes at the end. However, the author's assigned task of filling a gap in the literature for a varied audience of undergraduates, post-graduate students and working economists as well as those doing research in the field of technical development inevitably proved to be too difficult. It means that many conclusions have to be accepted at their face value. On the contrary, at the end of the second section of thepresent article a ‘CS’ model is constructed that allows for a more exact analysis of the important question about the absorptive power of an economic system with regard to the consequences of labour-saving technological pushes. The third section deals more fully with the author's treatment of Von Bohm-Bawerk's roundabout production theory. Improvements are suggested in this section as well as in the concluding fourth section.

Incentives to cooperate in linear quadratic difference games

Abstract: Linked macroeconometric policy models can often be regarded as linear quadratic N-person non-zero-sum difference games. In this paper we study sufficient conditions for the Nash optimal strategies to be Pareto optimal.

Simulation of a queueing problem with balking

Abstract: Queueing systems become complicated if balking occurs, that is, if impatient customers refuse to join the queue. Analytical results for expected queue length and waiting time have been obtained for the standard queueing problem (M/M/1) with balking. This report describes an investigation into the general validity of these formulas.Since an analytical approach to the general queueing problem is not feasible, we used simulation. An efficient simulation model was constructed and ana lysed using regenerative properties, a technique for handling correlated observations. The results extend standard queueing theory and indicate areas for further theoretical investigation.

Stackelberg solutions in macroeconometric policy models with a decentralized decision structure

Abstract: Macroeconometric policy models with a decentralized decision structure can often be viewed upon as a linear quadratic N-person nonzero sum difference game with exogenous inputs, nonfeasible ideal paths and a fixed time horizon. When the decision structure is also hierarchical, the Stackelberg solution concept can be used to model the decision structure. In this paper the open loop and feedback Stackelberg strategies for such a game are derived and an application is given in the form of a small linked econometric model for the Common Market.

Small-sample behavior of Weighted Least Squares in experimental design applications

Abstract: In experimental design applications unbiased estimators s2i of the variances σ2i are possible. These estimators may be used in Weighted Least Squares (WLS) when estimating the parameters β The resulting small-sample behavior is investigated in a Monte Carlo experiment. This experiment shows that an asymptotically valid covariance formula can be used if s2i is based on, say, at least 5 observations. The WLS estimator based on estimators s2i gives more accurate estimators of β, provided the σ2i differ by a factor, say, 10.

The case of labour time reduction without wage compensation: More or less employment?

Abstract: In this paper a model of a closed economy, including a market sector and a public sector, is presented to analyse the consequences of a reduction of labour time with and without wage compensation. It turns out that a policy of labour time reduction without wage compensation is a very strong instrument to improve production and employment, if the economy is characterized by the Keynesiandemand model. But if the economy is characterized by the neoclassicalsupply model, a relatively large drop in wages is necessary to prevent a policy of labour time reduction from causing a process of stagflation.