Assessing the Interaction between Real Estate and Equity in Households Portfolio Choice.

In this paper, we provide a new empirical analysis of the dynamic portfolio decisions of households by simultaneously considering their stock market participation and home tenure choices. There is already a huge body of literature on housing status (own/rent) decisions and many contributions documented the low stock market participation rate of US households. Although some papers evidenced that the home status (modeled as an exogenous variable) has an impact on the stock proportion in portfolio, our paper is the first one to allow both decisions (home and stock) to be simultaneous and endogenous. We estimate a dynamic bivariate logistic panel data model on Panel Study of income Dynamics data from 1999 to 2007 controlling for sample selection bias and time-invariant unobserved heterogeneity. We first evidence that our original joint setup outperforms a standard one (with two distinct equations for stock holdings and for home tenure), i.e. marginal odds ratios are significant. Using these estimates, we are able to simulate individual paths of stock and home equity positions over the life cycle according to households attributes. Ceteris Paribus, we show that households taking positions in one asset (home or stock) encounter a positive position in the other asset at an earlier stage in their life cycle, i.e. some households appear to be locked in a no-stock-and-renter position.households; Investment;

Assessing the Interaction between Real Estate and Equity in Households Portfolio Choice

In this paper, we provide a new empirical analysis of the dynamic portfolio decisions of households by simultaneously considering their stock market participation and home tenure choices. There is already a huge body of literature on housing status (own/rent) decisions and many contributions doc- umented the low stock market participation rate of US households. Although some papers evidenced that the home status (modeled as an exogenous variable) has an impact on the stock proportion in portfolio, our paper is the …rst one to allow both decisions (home and stock) to be simultaneous and endogenous. We estimate a dynamic bivariate logistic panel data model on Panel Study of income Dynamics data from 1999 to 2007 controlling for sample selection bias and time-invariant unobserved heterogeneity. We …rst evidence that our original joint setup outperforms a standard one (with two distinct equations for stock holdings and for home tenure), i.e. marginal odds ratios are signi…cant. Using these estimates, we are able to simulate individual paths of stock and home equity positions over the life cycle according to households attributes. Ceteris Paribus, we show that households taking positions in one asset (home or stock) encounter a positive position in the other asset at an earlier stage in their life cycle, i.e. some households appear to be locked in a no-stock-and-renter position.Housing, Stock market participation, Portfolio choices, Panel Data

Reliability and Cost Evaluation of Third-Generation Wireless Access Network Topologies: A Case Study

Abstract-The "explosive growth in bursty traffic" changes the network dynamics and requires a good evaluation of various classes of service when designing an access network. From a topological standpoint, the multiservice networks in this paper are heterogeneous systems which integrate both a core and some wireless access networks into an infrastructure similar to third-generation wireless networks. Such networks require reliable and cost-effective solutions to the problem of selecting access technologies for satisfying performance and quality of service requirements related to the services and applications envisioned. This paper analyzes the reliability aspects of some access network topologies to insure a certain level of quality of service at the lowest cost for the end users. It considers a mass market equivalent to 1.6 million subscribers, the objective being to determine the cost the users are ready to pay to benefit from services and applications provided by these multiservice networks. For these purposes, the relative behavior of 3 access-network topologies are studied: the tree with parallel backup links, the ring, and the partially meshed topologies. In ring topology, simulation results show that a great connectivity in the access network is not justified in terms of reliability requirements; the partially meshed topology, even if it has redundant links which affect its cost, outperforms the tree with parallel backup links; and the ring topology is more reliable in terms of disconnected sessions than the tree topology. By considering both reliability and cost, a tree with parallel backup links appears the best topology for the access network and its cost is acceptable for the end user. This study can be extended by: 1) establishing the cost as a function of the quality of service; 2) optimizing the partially meshed topology for more reliable networks; and 3) defining a (shaping) policy to deal with a variety of traffic schemes. Index Terms-Access network, cost evaluation, multi-service network, quality of service, third-generation wireless network, topological design. ACRONYMS AND ABBREVIATIONS 1 ADSL asymmetric digital subscriber line AR access router ATM asynchronous transfer mod

Approche dynamique et apprentissage du lancer du javelot

Approche nouvelle des problèmes liés à l'enseignement ou à l'entraînement en lancer du javelot. Application concrète de la théorie des systèmes dynamiques et de l'apprentissage moteur, s'inspirant des positions de D. Delignières