Has Competition in the Japanese Banking Sector Improved?

This paper investigates whether competition in the Japanese banking sector has improved in the last quarter of the 20th century. By estimating the first order condition of profit maximization, together with the cost function and the inverse demand function, we found that competition had improved, especially in the 1970s and in the first half of the 1980s. The results fail to reject a Cournot oligopoly for city banks for most of the period, while they do reject it for regional banks for the overall period. This suggests that competition among city banks was stronger than that among regional banks.Japanese banks, degree of competition, loan market.

Firm Growth and Efficiency in the Banking Industry : A New Test of the Efficient Structure Hypothesis

In this paper we propose a new test of the efficient structure (ES) hypothesis, which predicts that efficient firms come out ahead in competition and grow as a result. Our test has significant advantages over existing ones, because it is more direct, and can jointly test the so-called quiet-life hypothesis, which predicts that in a concentrated market firms do not minimize costs. We then apply this test to large banks in Japan. Consistent with the ES hypothesis, we find that more efficient banks become larger. We also find that market concentration reduces banks’ efficiency, which supports the quiet-life hypothesis. These findings imply that there is an intriguing growth-efficiency dynamic throughout banks’ life cycle, although our findings also suggest that the ES hypothesis dominates the quiet-life hypothesis in terms of economic impact

Firm Growth and Efficiency in the Banking Industry : A New Test of the Efficient Structure Hypothesis

This paper proposes a new test of the efficient structure hypothesis by directly examining the relation between firm efficiency and firm growth. This is also a test of the so-called quiet-life hypothesis.Applying this test to large banks in Japan, we find that more efficient banks become larger, which is consistent with the efficient structure hypothesis. We also find that market concentration reduces banks’ cost efficiency, which is consistent with the quiet-life hypothesis. These findings imply that there is an intriguing growth-efficiency dynamic throughout the life cycle of banks, although yet another finding suggests that the economic impact of the quiet-life hypothesis is less significant than that of the efficient structure hypothesis

Efficiency Structure Hypothesis versus Structure-Conduct-Performance Hypothesis Revisited (Japanese)

This paper examines whether the efficiency structure hypothesis holds true for major Japanese commercial banks using panel data covering fiscal years 1974-2001. The efficiency structure hypothesis has been hitherto mostly examined in comparison with the structure-conduct-performance (SCP) hypothesis in the framework that determines which of the two measurements - the degree of market concentration or market shares - better explains market performance such as profits and interest rates. In this paper, we point out problems of this framework and examine the efficiency structure hypothesis in a more straightforward way by focusing on the proposition that the more efficient a bank is the more it grows. Also, the paper provides analysis of the SCP hypothesis that is formulated as follows: the more a bank grows, the more inefficient it becomes. Specifically, we estimate organizational inefficiencies and the diseconomy of scale for each major bank using the panel data. Then we examine how these estimates affect the bank's size in the next year, and in reverse how they are affected by the growth of the bank. The estimation results show: (1) the efficiency structure hypothesis is supported by the organizational efficiency, but not by the diseconomy of scale; and (2) the SCP hypothesis is not necessarily supported.

Test of the Efficiency Structure Hypothesis with an Application to Japanese Major Banks (Japanese)

This paper examines whether the efficiency structure hypothesis holds true for Japanese major commercial banks using a panel data set covering the period from fiscal year 1974 to 2001. The efficiency structure hypothesis has been hitherto mostly examined in comparison with the structure-conduct-performance (SCP) hypothesis in the framework that determines which of the two measurements - the degree of market concentration or market shares - better explains market performance such as profits and interest rates. In this paper, we point out some problems of this framework and examine the efficiency structure hypothesis in a more straightforward manner by focusing on the proposition that the more efficient a bank the more it grows. First, we estimated organizational inefficiencies and the diseconomy of scale for each major bank using the panel data set. Then, we examined how these estimates for a certain bank in a certain year affect the bank's size in the next year. The regression analysis, in which the organizational inefficiencies and the diseconomy of scale in the preceding fiscal year are linked to the reduced-form equation for bank loans, has found that organization inefficiencies adversely affect the amount of bank loans, just as expected. However, contrary to our expectation, the impact of the diseconomy of scale vis-a-vis bank loans has turned out to be positive. Meanwhile, we have found that both organizational inefficiencies and the diseconomy of scale have a negative impact on the amount of bank assets, which is consistent with the efficiency structure hypothesis.

Transfer of Plasmid pJP4 from Escherichia coli to Activated Sludge Bacteria by filter Mating

『大阪大学大学院工学研究科環境・エネルギー工学専攻生物圏環境工学領域 研究活動報告』, (2009.4.1～2010.3.31), pp.101-107, 大阪大学大学院工学研究科環境・エネルギー工学専攻環境資源・材料学講座生物圏環境工学領域, 2010.5 に掲

Influence of myopotential interference on the Wavelet discrimination algorithm in implantable cardioverter-defibrillator

Background: Wavelet is a morphology-based algorithm for detecting ventricular tachycardia. The electrogram (EGM) source of the Wavelet algorithm is nominally programmed with the Can-RV coil configuration, which records a far-field ventricular potential. Therefore, it may be influenced by myopotential interference. Methods: We performed a retrospective review of 40 outpatients who had an implantable cardioverter-defibrillator (LCD) with the Wavelet algorithm. The percent-match score of the Wavelet algorithm was measured during the isometric chest press by pressing the palms together. We classified patients with percent-match scores below 70% due to myopotential interference as positive morphology change, and those with 70% or more as negative morphology change. Stored episodes of tachycardia were evaluated during the follow-up. Results: The number of patients in the positive morphology change group was 22 (55%). Amplitude of the Can-RV coil EGM was lower in the positive morphology change group compared to that in the negative group (3.9 +/- 1.3 mV vs. 7.4 +/- 1.6 mV, P=0.0015). The cut-off value of the Can-RV coil EGM was 5 mV (area under curve, 0.89). Inappropriate detections caused by myopotential interference occurred in two patients (5%) during a mean follow-up period of 49 months, and one of them received an inappropriate LCD shock. These patients had exhibited positive morphology change. Conclusions: The Wavelet algorithm is influenced by myopotential interference when the Can-RV coil EGM is less than 5 mV

Hybrid technique of cortical bone trajectory and pedicle screwing for minimally invasive spine reconstruction surgery : A technical note

The pedicle screw (PS) system is widely used for spinal reconstruction. Recently, screw insertion using the cortical bone trajectory (CBT) technique has been reported to provide increased holding strength of the vertebra, even in an osteoporotic spine. CBT is also beneficial due to its low invasiveness. We have been performing hybrid reconstruction with CBT at the cranial level and PS at the caudal level based on the concept of minimal invasiveness. We applied this hybrid technique to 6 cases of degenerative spondylolisthesis. Surgery was completed with a small skin incision of around 5-6 cm, which is shorter than that of the conventional PS procedure. The mean percent slippage before surgery was 19.8%, and this was reduced to 3.9% after surgery and almost maintained 3 months after surgery. Furthermore, no major surgical complications were observed. Here, we introduce the minimally invasive hybrid technique of CBT-PS. Surgeons should be aware of the procedure as an option for minimally invasive lumbar spine reconstructive surgery