An Emergency Evacuation Planning Model Using the Universally Quickest Flow

In recent years, catastrophic disasters by massive earthquakes have been increasing in the world, and disaster management is required more than ever. In the case of disasters such as tsunamis, a slight delay in evacuation may deprive evacuees of life. In this article, we formalize the emergency evacuation planning model for evacuation from tsunamis and other disasters based on the idea of the universally quickest flow. We show that there does not always exist a universally quickest flow when the capacity constraint of refuges is taken into account. Therefore, we propose an alternative criterion that approximates a universally quickest flow, and presents an algorithm for finding an optimal flow for this criterion. Numerical experiments are carried out for the evacuation of a local city in Japan where tsunami damages are assumed to occur when a large earthquake occurs in the ocean nearby.     

Inference on impulse response functions in structural VAR models

Skepticism toward traditional identifying assumptions based on exclusion restrictions has led to a surge in the use of structural VAR models in which structural shocks are identified by restricting the sign of the responses of selected macroeconomic aggregates to these shocks. Researchers commonly report the vector of pointwise posterior medians of the impulse responses as a measure of central tendency of the estimated response functions, along with pointwise 68% posterior error bands. It can be shown that this approach cannot be used to characterize the central tendency of the structural impulse response functions. We propose an alternative method of summarizing the evidence from sign-identified VAR models designed to enhance their practical usefulness. Our objective is to characterize the most likely admissible model(s) within the set of structural VAR models that satisfy the sign restrictions. We show how the set of most likely structural response functions can be computed from the posterior mode of the joint distribution of admissible models both in the fully identified and in the partially identified case, and we propose a highest-posterior density credible set that characterizes the joint uncertainty about this set. Our approach can also be used to resolve the long-standing problem of how to conduct joint inference on sets of structural impulse response functions in exactly identified VAR models. We illustrate the differences between our approach and the traditional approach for the analysis of the effects of monetary policy shocks and of the effects of oil demand and oil supply shocks.     

Dynamic analysis of outsourcing

This paper develops an R&D-based growth model and calibrates the model to aggregate data of the US economy to quantify a structural relationship between patent length, R&D and consumption. Under parameter values that match the empirical flow-profit depreciation rate of patents and other key features of the US economy, extending the patent length beyond 20 years leads to a negligible increase in R&D despite equilibrium R&D underinvestment. In contrast, shortening the patent length leads to a significant reduction in R&D and consumption. Finally, this paper also analytically derives and quantifies a dynamic distortionary effect of patent length on capital investment.     

On sooner and later waiting time distributions associated with simple patterns in a sequence of bivariate trials

In this article, we study sooner/later waiting time problems for simple patterns in a sequence of bivariate trials. The double generating functions of the sooner/later waiting times for the simple patterns are expressed in terms of the double generating functions of the numbers of occurrences of the simple patterns. Effective computational tools are developed for the evaluation of the waiting time distributions along with some examples. The results presented here provide perspectives on the waiting time problems arising from bivariate trials and extend a framework for studying the exact distributions of patterns. Finally, some examples are given in order to illustrate how our theoretical results are employed for the investigation of the waiting time problems for simple patterns.     

Who values the family‐friendly aspects of a job? Evidence from the Japanese labour market

Women with family responsibilities such as child‐rearing generally prefer jobs with flexible working conditions. According to the theory of compensating wage differentials, women working in such family‐friendly jobs are paid less than those working in family‐unfriendly jobs. The present paper investigates whose wages are more greatly affected by the family‐(un)friendly aspects of their jobs. Based on a longitudinal survey of Japanese women, we found that among several family‐(un)friendly attributes of a job, only commuting time requires a wage premium, and most of the premium is associated with job changes made by part‐time‐working married women.     

Finitely repeated games with monitoring options

We study finitely repeated games where players can decide whether to monitor the other players? actions or not every period. Monitoring is assumed to be costless and private. We compare our model with the standard one where the players automatically monitor each other. Since monitoring other players never hurts, any equilibrium payoff vector of a standard finitely repeated game is an equilibrium payoff vector of the same game with monitoring options. We show that some finitely repeated games with monitoring options have sequential equilibrium outcomes which cannot be sustained under the standard model, even if the stage game has a unique Nash equilibrium. We also present sufficient conditions for a folk theorem, when the players have a long horizon.     

Policy trade-off in the long run: A new Keynesian model with technological change and money growth

In this study, we introduce a constant rate of technological change and money growth into the standard new Keynesian model, in which both prices and nominal wages are supposed to be sticky. Using such a model, we examine whether a policy trade-off exists between curbing inflation and stabilizing the welfare-relevant output gap in the steady state. If we take only price stickiness into consideration, a policy trade-off does not occur. However, if both nominal wage stickiness and price stickiness are taken into consideration, a policy trade-off occurs.