A matching prior for extreme quantile estimation of the generalized Pareto distribution

Extreme quantile estimation plays an important role in risk management and environmental statistics among other applications. A popular method is the peaks-over-threshold (POT) model that approximate the distribution of excesses over a high threshold through generalized Pareto distribution (GPD). Motivated by a practical financial risk management problem, we look for an appropriate prior choice for Bayesian estimation of the GPD parameters that results in better quantile estimation. Specifically, we propose a noninformative matching prior for the parameters of a GPD so that a specific quantile of the Bayesian predictive distribution matches the true quantile in the sense of Datta et al. (2000).     

International labor migration and social security: Analysis of the transition path

This paper numerically simulates a two-country overlapping-generations model to study international labor migration when the two countries are characterized by different social-security systems. The present analysis extends previous work beyond steady-state considerations. The most striking result is that in all cases considered, dynamically efficient and inefficient economies in autarkic steady-state, migration leads to temporary welfare losses in both countries. In all cases, the transition path is characterized by temporary dynamic inefficiency in one country.All correspondence to Doris Geide-Stevenson. We would like to thank an anonymous referee for very helpful comments. We are responsible for any remaining errors. Responsible editor: Christoph M. Schmidt.     

Is there early take-off phenomenon in diffusion of IP-based telecommunications services?

Traditionally, the diffusion of telecommunications services has been considerably affected by the presence of critical mass and network externalities, and thus has shown the so-called “late take-off” phenomenon. However, as telecommunications networks evolve from circuit switching to packet switching, especially IP networks, and thus enabling diverse new services, it seems these traditional telecommunications diffusion patterns are changing. By comparing the diffusion of IP-based services with those of circuit-based services and durable goods, we have found the late take-off phenomenon is not involved in the diffusion of newly introduced IP-based services. Moreover, we concluded that the diffusion of IP-based services is much faster than that of durable goods, thus showing an “early take-off” phenomenon. Based on this empirical result, we suggest that telcos (telecommunications companies) and (ISPs) Internet service providers should pay as much attention to the growth stage as the introduction stage in their development, in order for their IP-based services to be successful in the market.     

Experience-weighted Attraction Learning in Normal Form Games

In ‘experience-weighted attraction’ (EWA) learning, strategies have attractions that reflect initial predispositions, are updated based on payoff experience, and determine choice probabilities according to some rule (e.g., logit). A key feature is a parameter δ that weights the strength of hypothetical reinforcement of strategies that were not chosen according to the payoff they would have yielded, relative to reinforcement of chosen strategies according to received payoffs. The other key features are two discount rates, φ and ρ, which separately discount previous attractions, and an experience weight. EWA includes reinforcement learning and weighted fictitious play (belief learning) as special cases, and hybridizes their key elements. When δ= 0 and ρ= 0, cumulative choice reinforcement results. When δ= 1 and ρ=φ, levels of reinforcement of strategies are exactly the same as expected payoffs given weighted fictitious play beliefs. Using three sets of experimental data, parameter estimates of the model were calibrated on part of the data and used to predict a holdout sample. Estimates of δ are generally around .50, φ around .8 − 1, and ρ varies from 0 to φ. Reinforcement and belief-learning special cases are generally rejected in favor of EWA, though belief models do better in some constant-sum games. EWA is able to combine the best features of previous approaches, allowing attractions to begin and grow flexibly as choice reinforcement does, but reinforcing unchosen strategies substantially as belief-based models implicitly do.     

Child’s gender,parental monetary investments and care of elderly parents in China

Review of Economics of the Household - This study analyzes whether parental monetary investments in children stimulate support from sons and daughters. Using data from the China Health and...     

Can digital signals from the keyboard capture force exposures during typing?

An exposure-response relationship has been shown between muscle fatigue and its effects on keystroke durations. Since keystroke durations can readily be measured by software programs, the method has the potential as a non-invasive exposure assessment tool. However, the software based keystroke durations may be affected by keyswitch force-displacement characteristics. Thus, this study used a force platform to measure the keystroke durations and compared them to software measured keystroke durations in order to determine whether the software based keystroke durations can be used as a surrogate force exposure measures. A total of 13 subjects (6 males and 7 females) typed for 15 minutes each on three keyboards with different force-displacement characteristics. The results showed that the software based keystroke durations were more sensitive to the keyboard force-displacement differences than the force based measures. Although the digital signal based keystroke durations depend on the force-displacement characteristics, the high correlation between the two measures indicated that the keystroke durations derived from the digital signal approximated the true force derived keystroke durations, regardless of the keyboard force-displacement characteristics. Therefore, the software based keystroke durations could be used as a non-invasive, surrogate force exposure measure in lieu of the more invasive actual force measurements.     

TESTS FOR DETECTING MORE NBU-NESS AT A SPECIFIC AGE

This paper proposes a class of non‐parametric test procedures for testing the null hypothesis that two distributions, F and G, are equal versus the alternative hypothesis that F is ‘more NBU (new better than used) at specified age t₀’ than G. Using Hoeffding's two‐sample U‐statistic theorem, it establishes the asymptotic normality of the test statistics and produces a class of asymptotically distribution‐free tests. Pitman asymptotic efficacies of the proposed tests are calculated with respect to the location and shape parameters. A numerical example is provided for illustrative purposes.