对外贸易与近代云南统一市场的形成及其空间结构

口岸开放与对外贸易的发展推动了近代云南市场格局的变化，从而大致在20世纪初全省统一市场形成。受口岸开放格局和对外贸易发展的影响，近代云南区域市场形成了蒙自—昆明、腾越—大理（下关）“双核”型空间结构。区域双核结构既是口岸开放—贸易发展的产物，又是近代云南三关贸易特征形成，特别是贸易地位形成的重要影响因素，还是近代云南经济发展不平衡的空间机制之一。     

Cautionary Note about R 2

The coefficient of determination (R ²) is perhaps the single most extensively used measure of goodness of fit for regression models. It is also widely misused. The primary source of the problem is that except for linear models with an intercept term, the several alternative R ² statistics are not generally equivalent. This article discusses various considerations and potential pitfalls in using the R ²'s. Specific points are exemplified by means of empirical data. A new resistant statistic is also introduced.     

On construction of constant block-sum partially balanced incomplete block designs

Abstract

Constant block-sum designs are of interest in repeated measures experimentation where the treatments levels are quantitative and it is desired that at the end of the experiments, all units have been exposed to the same constant cumulative dose. It has been earlier shown that the constant block-sum balanced incomplete block designs do not exist. As the next choice, we, in this article, explore and construct several constant block-sum partially balanced incomplete block designs. A natural choice is to first explore these designs via magic squares and Parshvanath yantram is found to be especially useful in generating designs for block size 4. Using other techniques such as pair-sums and, circular and radial arrangements, we generate a large number of constant block-sum partially balanced incomplete block designs. Their relationship with mixture designs is explored. Finally, we explore the optimization issues when constant block-sum may not be possible for the class of designs with a given set of parameters.     

Designs for symmetrical parallel line assays obtainable through group divisible designs

A wide class of block designs for symmetrical parallel line assays with even number of doses, obtainable through group divisible designs is considered. Several new designs can thus be obtained using group divisibledesigns. Group divisible designs are also shown to provide a unification of many exisiting designs which follow as special cases.     

商标平行进口的反垄断法规制

商标平行进口问题不仅仅是知识产权领域的问题,它还涉及到反垄断法的规制。用消尽论和默示许可论解决该问题存在诸多缺陷,应按照合理原则对商标平行进口问题进行反垄断规制。     

Diagnostics for non-linear regression

Sensitivity analysis in regression is concerned with assessing the sensitivity of the results of a regression model (e.g., the objective function, the regression parameters, and the fitted values) to changes in the data. Sensitivity analysis in least squares linear regression has seen a great surge of research activities over the last three decades. By contrast, sensitivity analysis in non-linear regression has received very little attention. This paper deals with the problem of local sensitivity analysis in non-linear regression. Closed-form general formulas are provided for the sensitivities of three standard methods for the estimation of the parameters of a non-linear regression model based on a set of data. These methods are the least squares, the minimax, and the least absolute value methods. The effectiveness of the proposed measures is illustrated by application to several non-linear models including the ultrasonic data and the onion yield data. The proposed sensitivity measures are shown to deal effectively with the detection of influential observations in non-linear regression models.     

Block designs for incomplete factorial treatment structures with two factors

Abstract

In this paper, the problem of obtaining efficient block designs for incomplete factorial treatment structure with two factors excluding one treatment combination for estimation of dual versus single treatment contrasts is considered. The designs have been obtained using the A-optimal completely randomized designs and modified strongest treatment interchange algorithm. A catalog of efficient block designs has been prepared for m₁?=?3, 4 and m₂?=?2, b?≤?10 and k?≤?9 and for m₁?=?3,4 and m₂?=?3, 4, b?≤?10 and k?≤?10.     

函数g（n）=2n＋2的整除性质的推广

将函数g（n）=2n＋2的整除性推广到更一般的函数f（n）=an＋a（n∈N＋,a为正偶数）的形式。     

国外职业教育实训基地建设对我国职业教育的启示

实训基地是职业教育的主课堂,是培养技能型人才的主要平台。国外职业教育实训基地有不同的类型,它们具有各自不同的内涵、形式和教学特色。研究国外职业教育实训基地的主要类型及其教学特色,对我国职业教育实训基地的建设和发展,具有重要的现实启迪。