日本存款准备金制度的历史演进

日本于1959年引入了存款准备金制度.在金融自由化前,存款准备金制度与再贴现率操作共同发挥着金融调节手段的作用.随着金融自由化的发展,人们逐渐意识到该制度会对银行存款业务的竞争力带来很大影响,因此下调了存款准备金率.20世纪90年代以后存款准备金率基本保持不变.作为日本银行诱导短期利率的一种框架,存款准备金制度现在仍有重要作用.     

The Bootstrap and the Edgeworth Correction for Semiparametric Averaged Derivatives*

In a number of semiparametric models, smoothing seems necessary in order to obtain estimates of the parametric component which are asymptotically normal and converge at parametric rate. However, smoothing can inflate the error in the normal approximation, so that refined approximations are of interest, especially in sample sizes that are not enormous. We show that a bootstrap distribution achieves a valid Edgeworth correction in the case of density‐weighted averaged derivative estimates of semiparametric index models. Approaches to bias reduction are discussed. We also develop a higher‐order expansion to show that the bootstrap achieves a further reduction in size distortion in the case of two‐sided testing. The finite‐sample performance of the methods is investigated by means of Monte Carlo simulations from a Tobit model.     

The effects of wild cruciferous host plants on morphology, reproductive performance and flight activity in the diamondback moth,Plutella xylostella (Lepidoptera: Yponomeutidae)

The wild crucifers,Rorippa indica andLepidium virginicum, are known to serve as host plants for the diamondback moth (DBM),Plutella xylostella, but they are less suitable than the preferred cultivated cruciferous plant, cabbage, in terms of adult body size and fecundity. The life history traits and flight activity of DBM adults grown on various host plants were investigated. The adults thus reared on each host plant were divided into three size groups (small, medium and large). In general, female adults grown on the wild crucifers were less fecund and lived longer than those reared on cabbage. Flight activity was higher in adults grown on wild crucifers than in those reared on cabbage. Male adults flew longer than females. Fecundity, longevity, flight activity and morphometrical characters of adults were positively correlated with pupal weight in individuals reared on the same host plant. A negative relationship was found between fecundity and flight activity in females of the same size group, but a positive one was observed in females reared on the same host plant.