The Optimal of Provision of Products with Income Effects

Discrete choice models have been used to describe imperfect competition between firms selling horizontally differentiated products. In all theoretical models, the indirect utility function is assumed to be linear in income so that there is no income effect. We consider here a situation in which income enters nonlinearly into the indirect utility function. We propose a correct (hicksian) measure of consumer surplus based on a willingness to pay principle. In order to grantee the existence of a price equilibrium, match values are assumed logconcavilly distributed. Using a correct measure of welfare, we extent the results of Anderson, de Palma and Nesterov to the case where income effects are involved. We proof that under these general assumptions, overentry prevails. Our findings, which extend the conventional discrete choice oligopoly approach provide various guidelines for empirical research.

A KINEMATIC COMPARISON OF JORDANIAN SPRINTERS IN RELATION TO LEG STRENGTH AND LENGTH

The purpose of this study was to compare the kinematic parameters with regard of their leg strength and length in performing 100m. dash. A twenty four sprinters were filmed by Sony - Video of 25 image/second from a perpendicular position to the sagittal plane of the 100m. sprinting execution. A group "a" were specialised in running (100 - 200 m), while a group "B" consists of (400 m) sprinters; of which each group consists of twelve sprinters. The distance of the 100 m was divided into four phases for the sake of the analysis and comparisons. Results indicate that in both groups, there was a significant difference in stride length and frequency in all phases of the 100 m except the fourth phase. It is also indicated that there is a linear correlation between limbs length and stride length. In addition, there was a parabolic relationship between limbs length and stride frequency. For both groups, it was indicated that there was no correlation between strength of lower extremities and stride length and frequency. Therefore it was concluded that the sprinters lack legs muscular strength. Thus, it was suggested to increase muscular strength training in their routine in order to improve their performance

On Different Strategies for Eliminating Redundant Actions from Plans

Satisficing planning engines are often able to generate plans in a reasonable time, however, plans are often far from optimal. Such plans often contain a high number of redundant actions, that are actions, which can be removed without affecting the validity of the plans. Existing approaches for determining and eliminating redundant actions work in polynomial time, however, do not guarantee eliminating the "best" set of redundant actions, since such a problem is NP-complete. We introduce an approach which encodes the problem of determining the "best" set of redundant actions (i.e. having the maximum total-cost) as a weighted MaxSAT problem. Moreover, we adapt the existing polynomial technique which greedily tries to eliminate an action and its dependants from the plan in order to eliminate more expensive redundant actions. The proposed approaches are empirically compared to existing approaches on plans generated by state-of-the-art planning engines on standard planning benchmark

Fetal-Neonatal Lifestyle Basis of the Adult Metabolic Syndrome Patients

Information on the health status in modern society and developed countries depicts an increase in noncommunicable diseases (NCDs) such as diabetes, overweight, obesity, and metabolic syndrome. An examination of factors related to this increase shows that there is a shift in the daily practices of the people, and especially children in all ages, as they grow older toward a more sedentary lifestyle. This chapter concentrated on the term used to describe lifelong changes in function that follow a particular event in an earlier period of the life span, which is called programming. These include the lifestyle in the fetus, pregnant woman, and parents; all of which affect pronounce metabolic syndrome in later life of adult. Therefore, regular physical activity and living systematic healthy lifestyle in the prenatal stages are of importance to genetic modification of inheritance for future generations

Transition choice probabilities and welfare analysis in random utility models

We study the descriptive and the normative consequences of attribute changes in standard discrete choice models. For additive random utility models, we derive expressions for the transition choice probabilities for a change in the systematic utility. We then use these expressions to compute the CDF’s of the compensating variation conditional on the initial and on the final choices. The conditional moments of the compensating variation are obtained as a one-dimensional integral of the transition choice probabilities. We also provide a stochastic version of Shephard’s Lemma when transitions are observed. Example of the logit and the disaggregated CES are also studied.Random Utility Models, Transition Choice Probabilities, Multinomial Logit Model, CES, Conditional Compensating Variation, Shephard’s Lemma.

Transition choice probabilities and welfare in ARUM's

We study the descriptive and the normative consequences of price and/or other attributes changes in additive random utility models. We first derive expressions for the transition choice probabilities associated to these changes. A closed-form formula is obtained for the logit. We then use these expressions to compute the cumulative distribution functions of the compensating variation conditional on ex-ante and/or ex-post choices. The unconditional distribution is also provided. The conditional moments of the compensating variation are obtained as a one-dimensional integral of the transition choice probabilities. This framework allows us to derive a stochastic version of Shephard's lemma, which relates the expected conditional compensating variation and the transition choice probabilities. We compute the compensating variation for a simple binary linear in income choice model and show that the information on the transitions leads to better estimates of the compensating variation than those obtained when only ex-ante or ex-post information on individual choices is observed. For the additive in income logit, we compute the conditional distribution of compensating variation, which generalizes the logsum formula. Finally, we derive a new welfare formula for the disaggregated version of the represen- tative consumer CES model.Additive random utility models (ARUM), Logit, Transition choice probabilities, Compensating variation, Shephard's Lemma, Logsum, CES

KINEMATICAL ANALYSES OF TWO STYLES IN BREAST STROKES SWIMMING

In order to determine the best wave style technique for the youth Jordanian breaststrokers and to accurately pin point the differences in the kinematics variables a 3D analysis was conducted. Therefore, the purpose of this study was to investigate some kinematics variables of both styles: the Hip Wave Undulation (HWU) and the Hip Wave Undulation with Feet Breaking Surface (HWUBS), and to compare the variables: Stroke Length SL, Stroke Rate SR, Velocity V, Stroke Time ST, Hip Displacement HD and Feet Displacement FD. Subjects were assigned to swim at their maximum speed with both styles at different order so that the best trial according to their time was analyzed. Both males and females showed an intriguing feature of the CG body velocity curve per cycle and both had decreasing velocity in slow rate when they used (HWUBS). Thus, one may conclude that an exaggerated hip undulation was executed to allow for feet to break the surface of the water which affected their velocity reduction during the stroke cycle

First verbs : On the way to mini-paradigms

This 18th issue of ZAS-Papers in Linguistics consists of papers on the development of verb acquisition in 9 languages from the very early stages up to the onset of paradigm construction. Each of the 10 papers deals with first-Ianguage developmental processes in one or two children studied via longitudinal data. The languages involved are French, Spanish, Russian, Croatian, Lithuanien, Finnish, English and German. For German two different varieties are examined, one from Berlin and one from Vienna. All papers are based on presentations at the workshop 'Early verbs: On the way to mini-paradigms' held at the ZAS (Berlin) on the 30./31. of September 2000. This workshop brought to a close the first phase of cooperation between two projects on language acquisition which has started in October 1999: a) the project on "Syntaktische Konsequenzen des Morphologieerwerbs" at the ZAS (Berlin) headed by Juergen Weissenborn and Ewald Lang, and financially supported by the Deutsche Forschungsgemeinschaft, and b) the international "Crosslinguistic Project on Pre- and Protomorphology in Language Acquisition" coordinated by Wolfgang U. Dressler in behalf of the Austrian Academy of Sciences

Estimation of bivariate excess probabilities for elliptical models

Let $(X,Y)$ be a random vector whose conditional excess probability $\theta(x,y):=P(Y\leq y | X>x)$ is of interest. Estimating this kind of probability is a delicate problem as soon as $x$ tends to be large, since the conditioning event becomes an extreme set. Assume that $(X,Y)$ is elliptically distributed, with a rapidly varying radial component. In this paper, three statistical procedures are proposed to estimate $\theta(x,y)$ for fixed $x,y$, with $x$ large. They respectively make use of an approximation result of Abdous et al. (cf. Canad. J. Statist. 33 (2005) 317--334, Theorem 1), a new second order refinement of Abdous et al.'s Theorem 1, and a non-approximating method. The estimation of the conditional quantile function $\theta(x,\cdot)^{\leftarrow}$ for large fixed $x$ is also addressed and these methods are compared via simulations. An illustration in the financial context is also given.Comment: Published in at http://dx.doi.org/10.3150/08-BEJ140 the Bernoulli (http://isi.cbs.nl/bernoulli/) by the International Statistical Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm