Testing hypotheses when there could be an initial effect

In many treatment-versus-control experiments, the observed random variables can be written as the product of a Bernoulli and a continuous random variable. The treatment can affect the distribution of the observations in two ways.

1. the probability that the observation is 0 could be altered.

2. the distribution of the nonzero observations could be changed.

We may also want to measure the combined effect of the treatment.

3. the expected value of control and treated units may differ.

A method is presented for testing for the presence of the combined effect when the general form of the distribution function of the continuous observations is known. For the case when this distribution function is from the family of gamma distributions, a previously proposed test criterion for the combined effect has poor power properties. In this paper, we discuss a test criterion that has improved power properties.     

Score tests in the two - way layout of counts

For the balanced two-way layout of a count response variable Y classified by fixed or random factors A and B, we address the problems of (i) testing for individual and interactive effects on Y of two fixed factors, and (ii) testing for the effect of a fixed factor in the presence of a random factor and conversely. In case (i), we assume independent Poisson responses with µ_ij= E(Y| A=i,B=j) = α_iβ_jγ_ij corresponding respectively to the multiplicative

interactive and non-interactive cases. For case (ii) with factor A random, we derive a multivariate gamma-Poisson model by mixing on the random variable associated with each level of A. In each case Neyman C(α) score tests are derived. We present simulation results,and apply the interaction test to a data set, to evaluate and compare the size and power of the score test for interaction between two fixed factors, the competing Poisson-based likelihood ratio test, and the F-tests based on the assumptions that √Y+1 or log(Y+1) are approximately normal. Our results provide strong evidence that the normal-theory based F-tests typically are very far from nominal size, and that the likelihood ratio test is somewhat more liberal than the score test.     

论Charles C.Fries的语料库语言学思想及方法

Charles C.Fries是被语料库语言学界遗忘的一位重量级人物。他既是美国结构主义的代表人物,同时也是一位具有超前意识的语料库语言学思想家和杰出实践者。他的一些语料库语言学思想及方法至今对语料库语言学仍具有指导意义。对其主要的语料库语言学思想及方法:真实客观的数据观、将语言对比特征作为研究的焦点以及实证的研究范式,进行了评述,并在最后指出其思想和方法上的一些缺陷。     

中国农业劳动力转移与农业劳动生产率趋同的实证分析

20世纪90年代以来,中国农业劳动生产率不仅发生了显著的趋同现象,而且已处于向稳态转型的最后阶段;这种趋同是农业产出增长率的变化和因农业劳动力转移而引起的农业就业增长率的变化的相互作用的结果,而且后者的贡献更大;如果仅凭经济系统的自我发展机制,我国区域农业劳动生产率差距终将不会自动消失。必须通过加大投资、进行制度创新、发展乡镇企业和第三产业等措施来人为地缩小区域农业劳动生产率差距,以协调区域经济发展。     

新中国五十年湖南中篇小说巡礼

新中国50年特别是新时期以来的湖南中篇小说,名篇佳构联袂而出,令人目不暇接,文苑震惊,有口皆碑,堪称湖南文学的代表。     

直接碘量法定量测定维生素C

在pH=3的盐酸酸性介质中,碘能定量地将还原型维生素C氧化为脱氢维生素C,淀粉为指示剂,用标准曲线法测定样品中维生素C的含量,从而建立了一种测定维生素C的新方法。该法具有准确度和精密度较高。操作简便,终点变色敏锐,对滴定剂(碘的乙醇溶液)不需要标定等特点。     

Developments in and prospects for external debt position and burden of developing countries: The case of Korea

The delay of strong economic recovery by industrialized nations, slowed world export growth, and higher interest rates have worsened the financial situation of a number of developing countries which have relied on external borrowings to sustain current account deficits and protect economic development. Recently, well-publicized concerns over the ability to these countries to repay their considerable debt burden have been raised. To shed light on these concerns, the paper focuses on Korea—one of the heavier debt-holding countries. It describes the process through which Korea has acquired its external debt over the past decade, assesses the trends in its debt burden, and presents prospects for the period 1982–1986. Using the Korean experience, the paper shows that the most common indicators used for evaluating foreign debt burden, such as the long-term service ratio, need to be supplemented by other measurements. In a world economy characterized by short-term debts with variable interest rates, the paper suggests that an important tool in analyzing the external debt burden should be the short-term debt burden.     

Asset markets and foreign exchange intervention: A model of the Belgo-Luxemburg economic union

In this article a general formulation of government intervention policies in the foreign exchange market is integrated in the framework of an asset market model. The policy reaction function is based on a trade off between exchange rate and reserve stock fluctuations; constant exchange rates and a pure float are derived as limiting cases of the intervention schedule. An exchange rate equation is derived from the short run portfolio equilibrium of the model and is successfully tested using data for the Belgo-Luxemburg Economic Union (1967–1979). Our policy conclusions contrast the European Snake constraints for the Belgian Franc with Artus's findings (IMF Staff Papers XXIII(2), July 1976) for the leading DM.     

中共十八大以来群众路线研究综述

中共十八大以来,国内学术界对群众路线的内涵、重大意义、历史进程、经验教训、制约因素以及贯彻群众路线的途径和方法等方面进行了多层次、多视角的研究和探讨,取得了丰硕成果。通过对这些成果进行系统梳理,勾勒出既有研究成果的总体脉络,以资后续研究参考。     

Macroeconomic imbalances in Europe: How to overcome the fallacy of unit labour costs

Policy recommendations based on unit labour costs (ULC) indices can lead to undesirable and counterproductive policies, because they do not reveal possible distortions in the base year. In this paper, we discuss the problems with the ULC-current account relation and provide an alternative measure for relative wage costs called Wage Competitive index (WCI) based on the assumption of convergence of the returns on capital. We show how to calculate it and that it is more efficient than traditional ULC and REER indicators. The implication is that policymakers should not focus on nominal wage setting only, but also more broadly on all factors which affect the return on capital. This implies that the well-known Rehn–Meidner rule, which underlies the Macroeconomic Dialogue should be modified.