Hepatocellular carcinoma: Prospective assessments of the T-factor with CT,US, and MR imaging

The capabilities of computed tomography (CT), ultrasonography (US), and magnetic resonance (MR) imaging were studied in order to determine the role of each of these noninvasive examinations for estimating the T-factor of hepatocellular carcinomas (HCCs). Fifty-one patients with surgically proven HCCs received CT (50 patients), US (46 patients), and MR (44 patients). The images of CT, US, and MR were prospectively evaluated for main tumor size, intrahepatic metastases, and vascular invasion, which compose the T-factor of HCC, and compared to pathological results. The sizes of the main tumor were estimated correctly by all examinations. For estimating intrahepatic metastases, US (74%) and MR (73%) were superior to CT (65%). For estimating portal invasion, CT (79%) was superior to US (70%) and MR (66%), because CT could demonstrate the segmental staining caused by portal invasion. The estimates of hepatic venous invasion were difficult during any of the examinations. We conclude that presurgical evaluations of the T-factor require the use of US and CT or MR and CT.     

Paradoxical trade patterns and terms of trade

It is shown that, when a monopoly is present in a two-country, two-commodity world, the terms-of-trade do not necessarily fall in between the pre-trade relative prices of the two countries, and that these pre-trade prices do not unequivocally determine the pattern of trade.     

An Explicit Finite Difference Approach to the Pricing Problems of Perpetual Bermudan Options

The pricing problem of options with an early exercise feature, such as American options, is one of the important topics in mathematical finance. Pricing formulas for options with the early exercise feature, however, are not easy to obtain and the numerical methods are thus frequently required to derive the price of these options. The value function of perpetual Bermudan options is characterized with the partial differential equation and this is solved by the finite difference method in this article.     

Out‐of‐Sample Exchange Rate Forecasting and Macroeconomic Fundamentals: The Case of Japan

This study explores the respective out‐of‐sample exchange rate forecasting abilities of five macroeconomic fundamental models in comparison to a naïve random walk model for Japan during the post‐Bretton Woods era. To assess the influence of major economic changes, we estimate both linear and nonlinear models for all the macroeconomic fundamentals. Overall, most structural exchange rate models outperform a naïve random walk model in terms of forecasting accuracy in the short horizon. When the fundamentals are only linearly modelled, the forecasting ability of the Taylor rule is generally superior to other fundamental models. When the fundamentals are nonlinearly specified, the predictability of some other models rises dramatically to match that of the Taylor rule models in short and/or long horizons. Of importance, we determine that the yen/dollar exchange rate forecasting performance effectively improves in several fundamental models when influential economic changes are incorporated.     

Multidimensional Poverty and Perceived Happiness: Evidence from China,Japan and Korea*

We compare multidimensional poverty and its associations with perceived happiness in China, Japan and Korea. Using largely comparable nationwide survey data, we focus on multidimensional poverty in terms of income, schooling, health and social protection. We find multidimensional poverty to be more prevalent in China than in Japan or Korea; sex and age‐based differences are largest in Korea. We further confirm significant associations between multidimensional poverty and perceived happiness. For all three countries, the aggregated poverty dimensions could largely identify unhappy individuals, with both wider coverage and higher odds than is possible through unidimensional analyses.     

A spatio-temporal model of house prices in the USA

This paper provides an empirical analysis of changes in real house prices in the USA using State level data. It examines the extent to which real house prices at the State level are driven by fundamentals such as real per capita disposable income, as well as by common shocks, and determines the speed of adjustment of real house prices to macroeconomic and local disturbances. We take explicit account of both cross-sectional dependence and heterogeneity. This allows us to find a cointegrating relationship between real house prices and real per capita incomes with coefficients (1,−1)$(1,-1)$, as predicted by the theory. We are also able to identify a significant negative effect for a net borrowing cost variable, and a significant positive effect for the State level population growth on changes in real house prices. Using this model we then examine the role of spatial factors, in particular, the effect of contiguous states by use of a weighting matrix. We are able to identify a significant spatial effect, even after controlling for State specific real incomes, and allowing for a number of unobserved common factors. We do, however, find evidence of departures from long run equilibrium in the housing markets in a number of States notably California, New York, Massachusetts, and to a lesser extent Connecticut, Rhode Island, Oregon and Washington State.     

The welfare effect of tariff rate reductions in a many country world

Consider a two-commodity n-country model without inferior goods where import tariffs are the only trade barriers. In this paper we establish that the world's welfare is improved if the country with the highest tariff rate unilaterally reduce its rate to the level of the second highest country or if all the countries of the world reduce tariff rates proportionally. The second rule serves as a theoretical justification of the Kennedy and Tokyo Round Tariff Reductions.     

A Generalization of Continuity and Convexity Conditions for Correspondences in Economic Equilibrium Theory

Fixed-point theorems for multi-valued mappings and economic equilibrium existence theorems are generalized from the viewpoint that the continuity and/or convexity assumptions on a mapping may be replaced by weaker local conditions on the vector field defined by the mapping. The generalization gives us natural conditions on individual (possibly non-ordered) preferences or aggregated demand behaviours so that we may obtain several extensions of recent results in social and game-theoretic equilibrium theories.
JEL Classification Numbers: C60, C62, C72, D50, D51.