Japan's resource imports

The paradox in Japan's external trade arises from the structure of Japan's international trade, that is, from its high dependence on a few major commodities on both the export and import sides. This structure implies that, should, for some reason, Japan's exports and/or imports be severely disrupted, the Japanese economy would be thrown into an economic chaos of formidable magnitude. Such was the case with the first oil shock of 1973-74. As the price of petroleum quadrupled, Japan's trade went into a deficit and its economy was thrown into a heavy recession coupled with a high inflation. On the other hand, when the terms of trade turn in favor of Japan, the economy enjoys a boom with stable prices as in the latest boom which began at the end of 1986. Japan's growth and inflation are quite sensitive to external economic conditions despite its low aggregate dependence on the foreign sector

Bubbles in Japan's stock market: A macroeconomic analysis

Since the 1950s, Japan's stock market has gone into bubbles every ten years or so (early 50s, early 60s, and early 70s). Then, the 1980s saw a strong bubble that went on for several years (late 1982 to the end of 1989). What caused this bubble to be so strong? Our analysis of the fundamental equation reveals that the key factor was the nominal interest rate which continued to decline until the late 1980s owing to the extremely relaxed monetary policy pursued by the Bank of Japan. Investors' stock price expectations added to the effect of low interest rates. We show that investors tend to forecast fluctuations on the real side two to three quarters ahead of time. The bubble crashed when investors' expectations collapsed. Since then, investors have remained bearish and the stock market has remained in the doldrums

Japan at a crossroads

Following our review of recent economic changes in Japan, we continue or study by speculating on the future course of macroeconomic changes of the IS balance and the trade balance associated with population aging and post-industrialization. Interpreting Japanese-style capitalism as a joint politics-bureaucracy-business utility maximization, we discuss the process of its demise as the collapse of this collective utility function

Predictability of conversation partners

Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information theoretic method to the spatiotemporal data of cell-phone locations, [C. Song et al. Science 327, 1018 (2010)] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one's conversation partners is defined as the degree to which one's next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to some extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual's predictability is correlated with the position in the static social network derived from the data. Individuals confined in a community - in the sense of an abundance of surrounding triangles - tend to have low predictability, and those bridging different communities tend to have high predictability.Comment: 38 pages, 19 figure

Non-cross-linking gold nanoparticle aggregation as a detection method for single-base substitutions

Aggregation of DNA-modified gold nanoparticles in a non-cross-linking configuration has extraordinary selectivity against terminal mismatch of the surface-bound duplex. In this paper, we demonstrate the utility of this selectivity for detection of single-base substitutions. The samples were prepared through standard protocols: DNA extraction, PCR amplification and single-base primer extension. Oligonucleotide-modified nanoparticles correctly responded to the unpurified products from the primer extension: aggregation for the full match and dispersion for all the mismatches. Applicability of this method to genomic DNA was tested with five human tumor cell lines, and verified by conventional technologies: mass spectrometry and direct sequencing. Unlike the existing methods for single-base substitution analysis, this method does not need specialized equipments, and opens up a new possibility of point-of-care diagnosis for single-nucleotide polymorphisms

Simultaneous Optimization of a Wheeled Mobile Robot Structure and a Control Parameter

A wheeled mobile mechanism with a passive and/or active linkage mechanism for traveling in the outdoor environment is developed and evaluated. In our previous research, we developed a wheeled mobile robot which has six wheels and a passive linkage mechanism, and its maneuverability was experimentally verified. The ability to climb over a 0.20 [m] high bump, which is twice height of the wheel diameter of 0.10 [m], was achieved, and the mobile robot can climb up continuous steps of 0.15 [m] high. In this research, we optimized the mobile robot linkage mechanisms and a controller parameter by evolutionary algorithm and dynamics engine in numerical simulations. The evolutionary algorithm employed in this research is Genetic Algorithm, and Open Dynamics Engine is used for dynamics calculation. To optimize the linkage mechanism and a controller parameter, we investigated outdoor environment for the mobile robot, for example obstacles, steps, and stairs. And, we selected typical three kinds of outdoor environments, 0.20 [m] high bump, right angle stairs of 0.15 [m] high, and angled stairs of 0.15 [m] high. In the numerical simulations, though the mobile robot using parameters which express our existing robot could climb up/down the 0.20 [m] high bump, but it could not achieve climbing up/down the two kinds of stairs. On the other hand, the optimized parameter mobile robot could climb up/down the three kinds of typical environments

Japanese-style capitalism

Japanese-style capitalism is a collusive system of national politics, elite bureaucracy, and big business. Elaborated in the course of rapid growth, it served Japan's post-war economic growth in flying colors. But on-going structural changes, induced by growth slowdown and population aging, now places Japanese-style capitalism in jeopardy. In this paper, we review these changes in the near past -- changes in the microeconomic sphere such as the family system, the employment system and the business system and changes in the macroeconomic sphere such as increasing part-time work in the labor market, slowdown in technical change, decline in manufacturing at home, persistence of trade surplus, and ongoing financial deepening

Saving and investment in Japan

This paper traces movements of saving and investment in the Japanese economy over the four decades after World War II. The postwar decades may be divided conveniently into four periods: the reconstruction period (1945-1952) in which saving was in absolutely short supply; the normalization period (1952-1959) when the economy returned to normalcy; the rapid growth period (1960-1973) when saving and investment were balanced at a very high level so as to make rapid growth achievable; and the slow grown period (1974-present) in which saving exceeded investment in the private economy. This paper presents international comparisons between the Japanese economy and other industrializing Asian economies that have high savings rates. The paper then examines the individual sectors of the economy -- personal savings ratios, corporate saving and investment ratios, fiscal policy, and monetary policy. This paper then explains the transition of the Japanese economy from a neoclassical model economy to a Keynesian model economy. Finally, the paper concludes with the hope that the private sector will begin investing again, in order to prevent disequilibria in the government and external sectors