A Taxi Zoning Analysis Using Large-Scale Probe Data: A Case Study for Metropolitan Bangkok

Taxis are considered one of the most convenient means of transportation, especially when people have to travel off-route, where public transportation is not a feasible option, and also when they need to reach a destination according to what is most convenient for them. However, many issues exist about taxi services, such as the problems of passengers who are unable to get taxi service at the location of their choice, or problems concerning when they need the taxi service to arrive. These problems may be due to the unavailability of the taxi at that particular location or due to the taxi driver not wanting to provide service. A taxi driver may not want to provide service to a potential passenger, because they may have preferences on the direction and areas they want to go or because of the different types of service zoning. Understanding the behaviors of taxi drivers and the characteristics of the trip/travel might be helpful to solving such issues. In this study, we conducted an analysis from a questionnaire survey and large-scale taxi probe data to understand taxi service behavior, travel characteristics, and to discover taxi service zoning characteristics. As a result, four types of taxi service zones including isolated zones, interactive zones, special service zones, and target zones were encountered. Travel characteristics were calculated and analyzed at different criteria, such as weekdays, weekends, and various time windows in a single day. The result of these characteristics was explained according to their similarities and dissimilarities in each type of zone. The discovery of the different zones and their respective definitions might be a good initiative for further development of a policy for taxi drivers to provide better service for passengers.     

Human resource management in Asian subsidiaries: comparison of French and Japanese MNCs

European and Japanese multinational corporations (MNCs) have expanded their activities in Asia, usually through massive mobilization of various human resources from head offices, whether expatriated or on short-term assignments, and a reliance on diverse categories of local employees. Because expatriation is costly, difficult and often limited in its results, MNCs have developed localization strategies for management positions to support their regional development. This contribution addresses such a scenario by comparing Japanese and French MNCs in eight Asian countries, based on 53 interviews across subsidiaries of 17 MNCs. We find that Japanese MNCs have not localized management positions as much as French MNCs, but they have grown more willing to do so. To compensate for the lack of local capabilities without sending more expatriates, both French and Japanese MNCs frequently send experts on short-term assignments. Finally, though human resource practices vary widely across countries, even for a given MNC, some harmonizing principles have been introduced to regional HRM strategies recently.     

Matrix exponential GARCH

I propose a new multivariate GARCH specification that maintains positive definiteness of the conditional covariance matrix. The idea is to specify the dynamics in the matrix logarithm of the conditional covariance. Because the matrix exponential transformation ensures positive definiteness, the dynamics can be specified without the positive definiteness constraint. This affords a variety of specifications and, in particular, we can specify element-by-element the dynamics of the matrix logarithm. I discuss specifications with leverage effects, estimation with multivariate Gaussian and t-distributions, and diagnostics that evaluate the appropriateness of the matrix exponential specification.     

Does the ‘persistence of profits’ persist?: a study of company profits in Japan, 1964–97

Earlier, in a time-series study of the profit rates of Japanese manufacturing firms, Odagiri and Yamawaki concluded that profits persist. With the addition of 15 more years of data up to 1997, this conclusion is shown to stand the test of time. In particular, those firms estimated to earn higher-than-average long-run profit rates in the early study were again estimated to earn higher-than-average long-run profit rates. The force of convergence was also found to be at work; for instance, the firms most profitable in Period 1 (1964–82) were most likely to face a decline in estimated long-run profit rates from Period 1 to Period 2 (1983–97). With the use of two sets of data, the firm’s profit performance was found to be positively related to measures of market share. First, among a smaller sample of firms for which reliable market share data could be matched, market share was estimated to have a significant positive effect on long-run profit rate in either period. Secondly, among the entire sample of 357 firms, the long-run profit rate in either period was estimated to be positively associated with firm sales relative to industry sales, which presumably is a crude measure of market share.     

Dynamic programming for non-additive stochastic objectives

We derive the existence of an optimum and the techniques of dynamic programming for non-additive stochastic objectives. Our key assumption for non-negative objectives is that asymptotic impatience exceeds asymptotic ‘mean’ growth, where ‘mean’ growth is derived not only from intertemporal inelasticity and the random return on investment but also from the curvature of the non-additive stochastic aggregator (i.e. the ‘certainty equivalent’). We provide broad families of new, interesting, and tractable examples. They illustrate that ‘mean’ growth can exist even when the distribution of returns has unbounded support, that power discounting often implies infinite asymptotic impatience, and that non-positive objectives are easily handled with few restrictions on growth.     

Nonlinear behavior of the socio-economic dynamics for lake eutrophication control

To succeed in combating lake eutrophication, cooperation of local inhabitants, small factories, and farmers in reducing phosphorus discharge is very important. But the willingness of each player to cooperate would depend on the cooperation of other players and on the level of environmental concern of the society in general. Here we study the integrated dynamics of people's choice of behavior and the magnitude of eutrophication. Assumptions are: there are a number of players who choose between alternative options: a cooperative and environment-oriented option is more costly than the other. The decision of each player is affected by “social pressure” as well as by economical cost of the options. The lake pollution increases with the total phosphorus released, and a high pollution level in the lake would enhance the social pressure. The model includes a positive and a negative feedback loops which create diverse dynamical behavior. The model often shows bistability — having an equilibrium with a high level of cooperation among people and clean water, and the other equilibrium with low cooperation and polluted water, which are simultaneously stable. The model also shows fluctuation between a high and a low levels of cooperation in alternating years, cycle with a longer periodicity, or chaotic fluctuation. Conservatism of people stabilizes the system and sometimes helps maintaining cooperation. The system may show unexpected parameter dependence — the improved phosphorus removing efficiency might make water more polluted if it causes the decline in the environmental concern and cooperation among people.     

Livelihood and care of the elderly: Determinants of public attitudes in Japan

This study analyses public attitudes towards the degree of government involvement in ensuring the livelihood and care of the elderly in Japan. Using four waves of individual-level annual data from the Japanese General Social Survey collected over the period 2000-2005, we estimate ordered logit models with various explanatory variables based on the socio-demographic, economic, political, and social background of the respondents. Many significant factors are common for both livelihood and care specifications, their effects being qualitatively the same and in line with our prior expectations. The estimation results also show positive coefficients of year intercept dummies, implying an increase in support of a government-based system over time. Further investigation shows that this trend is caused by those who favour government redistribution policies becoming increasingly more consistent in their support for a government-based social security system in Japan.     

Foreign direct investment,international trade,and firm heterogeneity

We present an asymmetric model with firm heterogeneity and foreign direct investment (FDI) from a developed country to a developing country. We found that the successful entry firms could be sorted from highest to lowest according to productivity as reimport firms, FDI firms, export firms, and domestic firms. We also found that FDI decreases (increases) the gross national income of the developed (developing) country, but it can either increase or decrease the world income according to the level of the relative propensity to spend. In addition, we demonstrated that FDI influences welfare through variations in average price, national income, and the number of types of goods.     

Japan's inflation under the Bretton Woods system: How large was the Balassa–Samuelson effect?

Japan's real exchange rate appreciation during the post-WWII manufacturing-led growth period has been regarded as a classical example of the Balassa–Samuelson effect. We choose the most conspicuous sub-period—1956–1970—to confirm the effect. Japan was in a rapid growth period under the U.S. dollar peg (real GDP growth, 9.7% per annum). The nominal anchor was weak as Japan's inflation rate (GDP deflator-based, 5.4%) was markedly higher than the U.S. rate (2.6%) during the 15-year period. The decomposition of the annual 2.7% (geometric) Japan–U.S. inflation rate gap (real exchange rate appreciation of the Japanese yen) reveals that the Balassa–Samuelson effect accounted for 0.7%; most of the real exchange rate appreciation (1.7%) was attributed to greater price increases in Japan's tradables. Although Japan's tradable sector achieved high TFP growth, the joint effect of the tradable–nontradable TFP growth difference between the two economies was too small to generate a sizable Balassa–Samuelson effect. Japan's example may suggest that even in rapidly growing economies, the magnitude of the effect in long-run real exchange rate appreciation is generally modest.