Trends in stock-bond correlations

Previous studies document the existence of long-run trends in comovements in the stock and bond markets. Following these findings, this article examines possible trends in stock-bond return correlations. To this end, we introduce a trend component into a smooth transition regression (STR) model including the multiple transition variables of Aslanidis and Christiansen (2012). The results indicate the existence of significant decreasing trends in stock-bond correlations for many advanced safer countries. In addition, although stock market volatility continues to be an important factor in stock-bond correlations, the short rate and yield spread become only marginally significant once we introduce the trend component. Our out-of-sample analysis also demonstrates that the STR model, including the volatility index and time trend as the transition variables, dominates other models. Furthermore, we find a significant increase in stock-bond correlations for riskier euro countries around the beginning of the euro crisis. Our findings of decreasing and increasing trends in stock-bond correlations can be considered a consequence of the decreasing effects of diversification and more intensive flight-to-quality behaviour that have taken place in recent years and after the euro crisis.     

International aid from the recipient perspective: public or private good input assistance?

This article proposes a theoretical model from the recipient perspective that considers what type of assistance a donor country should provide: public good assistance or private good assistance. We investigate the effects of migration and free riders under both types of assistance. We empirically apply this model to the rapidly growing economies and a large official development assistance disbursement for East Asia.     

Partial Communication in a Voluntary‐Contribution‐Mechanism Experiment

This paper presents results of a voluntary‐contribution‐mechanism experiment with partial communication. It was found that the trend of mean investments depended on whether a communication network was connected and on how fast all subjects could share information. When each subject could communicate with two other subjects and the network was connected, the mean investment increased from 33 percent to 58 percent of the optimal investment. On the other hand, when each subject could communicate with only one other subject and the network was not connected, the mean investment decreased from 34 percent to 19 percent of the optimal investment.     

Modified Quasi‐Likelihood Ratio Test for Regime Switching

In this paper we propose a modified quasi‐likelihood ratio test of the null hypothesis of one regime against the alternative of two regimes in Markov regime‐switching models. The asymptotic distribution of the proposed test statistic is a simple function of Gaussian random variables, and the inference is no more complicated than in the standard case. Our simulations show that the proposed test has good finite sample size and power that are comparable to the quasi‐likelihood ratio test of Cho and White. We apply our test to stock returns and Japanese policy functions.     

Detecting motives for cooperation in public goods experiments

This study clarifies the types of motives that are important as a source of cooperation in a linear public goods experiment. Our experimental design separates contributions into those due to confusion, one-shot motives (which includes altruism, warm-glow, inequality aversion, and conditional cooperation), and multi-round motives (which includes a strategic motive under incomplete information, a failure of backward induction, and reciprocity). The experiment reveals that multi-round motives plays an important role in driving cooperative behavior. Confusion and one-shot motives play a minor role.     

Fundamental impossibility theorems on voluntary participation in the provision of non-excludable public goods

Groves and Ledyard (Econometrica 45:783–809, 1977) constructed a mechanism attaining Pareto efficient allocations in the presence of public goods. After this path-breaking paper, many mechanisms have been proposed to attain desirable allocations with public goods. Thus, economists have thought that the free-rider problem is solved, in theory. Our view to this problem is not so optimistic. Rather, we propose fundamental impossibility theorems with public goods. In the previous mechanism design, it was implicitly assumed that every agent must participate in the mechanism that the designer provides. This approach neglects one of the basic features of public goods: non-excludability. We explicitly incorporate non-excludability and then show that it is impossible to construct a mechanism in which every agent has an incentive to participate.     

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.     

Characterizing Natural Implementability: The Fair and Walrasian Correspondences

We characterize natural implementability in exchange economies when a social choice correspondence possibly recommends a Pareto efficient allocation where the common marginal rate of substitution is not determined uniquely. We find that the no-envy and efficient (or fair) correspondence cannot be implemented by any natural mechanism with a price and a quantity announcement, but can be implemented by a natural mechanism with a price and two-quantity announcement. On the other hand, the constrained Walrasian correspondence can be implemented by a natural price-quantity mechanism with budget balance. Journal of Economic Literature Classification Numbers: C72, D51, D63, D78.