10世纪日本庄园的转变

日本庄园自8世纪起,经过约二百年的发展,到了10世纪发生了广泛而深刻的变革:庄园化程度进一步加深;越来越多的庄园实现了不输不入化,庄园领主获得了对庄园土地及土地上的人的一元化支配权;也是在此时期,庄园的经营方式由原来的雇佣经营为主,经由"散田请作体制"发展成为"名田"经营.所有这些变革都显示了与初期庄园明显不同的特征,表明了体制完备的领主制庄园已经形成,并且成为10世纪以后日本庄园的主要形态.     

A likelihood ratio test for goodness‐of‐fit of recessive and dominant models for case–control studies

Testing goodness‐of‐fit of commonly used genetic models is of critical importance in many applications including association studies and testing for departure from Hardy–Weinberg equilibrium. Case–control design has become widely used in population genetics and genetic epidemiology, thus it is of interest to develop powerful goodness‐of‐fit tests for genetic models using case–control data. This paper develops a likelihood ratio test (LRT) for testing recessive and dominant models for case–control studies. The LRT statistic has a closed‐form formula with a simple $\chi^{2}(1)$ null asymptotic distribution, thus its implementation is easy even for genome‐wide association studies. Moreover, it has the same power and optimality as when the disease prevalence is known in the population. The Canadian Journal of Statistics 41: 341–352; 2013 © 2013 Statistical Society of Canada     

Der Sequentieile Quotiententest bei irreduziblen homogenen Markovschen Ketten mit endlichem Zustandsraum

The Sequential Probaility Ratio Test is applied to test two simple hypotheses about the transition probability matrix of an irreducible homogeneous MARKOV chain with finite state space. An analogue (14) of Wald's Fundamental Identity, the Operating Characteristic Function (20-21) and the Average Sample Number (22-23) are given. These statements are generalizations of the MARKOV chain as well as some more conditions about the eigenvalues of the transition probability matrix.     

Trade sophistication in developing countries: Does export destination matter?

We investigate whether exports to developed economies stimulate export sophistication (represented by UNCTAD’s index of export similarity) in developing countries. Results from fixed-effects estimations suggest that exporting to developed economies enhances the sophistication of exports in the exporting country but there are diminishing returns to this effect. We also find non-linear effects from FDI and income on export sophistication with the effect of income exhibiting diminishing returns which suggests that the gains from exporting to developed economies are higher for lower-income countries; i.e., as income increases, the gains taper off. We discuss the policy implications of these results.     

Analysis of a two incongruent arrivals and services M/G/1 queue with random feedback

A queuing system with two incongruent arrivals and services is considered. Two kinds of customers enter the system by Poisson process and the service times are assumed to have general distribution. After first kind service completion, it may feedback to repeat the first service, leave the system or go to give second service. The same policy is applied for the other kind of customer. All stochastic processes involved in this system are independent. We derive the probability generating function for each kind and for the system that yield the performance measures. Some numerical approaches examined the validity of the results.     

Assessing additivity in nonparametric models —A kernel‐based method

In this article, we address the testing problem for additivity in nonparametric regression models. We develop a kernel‐based consistent test of a hypothesis of additivity in nonparametric regression, and establish its asymptotic distribution under a sequence of local alternatives. Compared to other existing kernel‐based tests, the proposed test is shown to effectively ameliorate the influence from estimation bias of the additive component of the nonparametric regression, and hence increase its efficiency. Most importantly, it avoids the tuning difficulties by using estimation‐based optimal criteria, while there is no direct tuning strategy for other existing kernel‐based testing methods. We discuss the usage of the new test and give numerical examples to demonstrate the practical performance of the test. The Canadian Journal of Statistics 39: 632–655; 2011. © 2011 Statistical Society of Canada