Using local linear kernel smoothers to test the lack of fit of nonlinear regression models

Herein, we propose a data-driven test that assesses the lack of fit of nonlinear regression models. The comparison of local linear kernel and parametric fits is the basis of this test, and specific boundary-corrected kernels are not needed at the boundary when local linear fitting is used. Under the parametric null model, the asymptotically optimal bandwidth can be used for bandwidth selection. This selection method leads to the data-driven test that has a limiting normal distribution under the null hypothesis and is consistent against any fixed alternative. The finite-sample property of the proposed data-driven test is illustrated, and the power of the test is compared with that of some existing tests via simulation studies. We illustrate the practicality of the proposed test by using two data sets.     

Adaptive tests of regression functions via multiscale generalized likelihood ratios

Many applications of nonparametric tests based on curve estimation involve selecting a smoothing parameter. The author proposes an adaptive test that combines several generalized likelihood ratio tests in order to get power performance nearly equal to whichever of the component tests is best. She derives the asymptotic joint distribution of the component tests and that of the proposed test under the null hypothesis. She also develops a simple method of selecting the smoothing parameters for the proposed test and presents two approximate methods for obtaining its P‐value. Finally, she evaluates the proposed test through simulations and illustrates its application to a set of real data.     

市场调查:图书选题计划制定的关键

加强市场调查对提高图书选题策划的预测准确性作用极大。市场导向和市场反馈,将直接有助于出版机构了解市场的饱和点、空白点、热点、增长点和萎缩点,正确判断图书市场的现状和未来走势,进而在制订选题计划时更为合理地进行因势利导和科学决策。     

COMPARISONS AND SELECTION OF TWO-PARAMETER EXPONENTIAL POPULATIONS

For two-parameter exponential populations with the same scale parameter (known or unknown) comparisons are made between the location parameters. This is done by constructing confidence intervals, which can then be used for selection procedures. Comparisons are made with a control, and with the (unknown) “best” or “worst” population. Emphasis is laid on finding approximations to the confidence so that calculations are simple and tables are not necessary. (Since we consider unequal sample sizes, tables for exact values would need to be extensive.)     

风险投资家的双重逆向选择风险规避机制

风险投资过程中,由于信息的不对称,投资者与风险投资家之间、风险投资家与风险企业家之间存在着双重逆向选择风险。在融资阶段的信号传递机制中,作为代理人的风险投资家,选择融资计划书信号,向作为委托人的投资者传递其能力信号,投资者据此修正自己的先验概率,然后根据后验概率,与风险投资家签定合同规避风险;在投资阶段的信息甄别机制中,作为中间委托人的风险投资家先提供合同,这时唯一可能是分离均衡,即不同类型的风险企业家选择不同的合同规避风险。     

论《红楼梦》“十二金钗“的入选与序次

排座论次是中国古典小说的一种重要文化现象。“十二金钗”的入选 ,基于封建末世大家族的各种悲剧类型 ,但又着重强调了“十二金钗”的门第和出身 ,“十二金钗”的序列先后又体现了曹雪芹的爱憎情感和道德评价。通过对《红楼梦》“十二金钗”的入选和序次的考察 ,有助于我们加深对曹雪芹思想及创作心态的理解     

江泽民关于选拔和培养优秀中青年干部的辩证思想

江泽民同志于 2 0 0 0年 6月在全国党校工作会议上的讲话 ,充满了实事求是的精神和深刻的辩证思维风格 ,体现了鲜明的时代特色。他对新时期干部德才基本要求所作出的新的规定 ,是对马克思主义人才理论的极大丰富。他提出的“重发现同时重培养”的原则、“使用、培养同一论”以及“德才具体说”、“辩证的台阶、资历观”等 ,是对传统的人才理论的突破和对马克思主义人才学说的丰富和发展     

SHOULD WE ESTIMATE THE PROBABILITY OF CORRECT SELECTION?

Various authors, given k location parameters, have considered lower confidence bounds on (standardized) dserences between the largest and each of the other k - 1 parameters. They have then used these bounds to put lower confidence bounds on the probability of correct selection (PCS) in the same experiment (as was used for finding the lower bounds on differences). It is pointed out that this is an inappropriate inference procedure. Moreover, if the PCS refers to some later experiment it is shown that if a non-trivial confidence bound is possible then it is already possible to conclude, with greater confidence, that correct selection has occurred in the first experiment. The short answer to the question in the title is therefore ‘No’, but this should be qualified in the case of a Bayesian analysis.     

An alternative to model selection in ordinary regression

The weaknesses of established model selection procedures based on hypothesis testing and similar criteria are discussed and an alternative based on synthetic (composite) estimation is proposed. It is developed for the problem of prediction in ordinary regression and its properties are explored by simulations for the simple regression. Extensions to a general setting are described and an example with multiple regression is analysed. Arguments are presented against using a selected model for any inferences.     

基于旅西日本游客旅游选择行为的西安旅游市场分析

根据在全国六大旅游热点城市所做的旅游市场调查的数据结果，对旅西日本游客的旅游选择行为进行了研究，同时进一步有针对性地对西安日本客源市场进行了SWOT分析，在此基础上，对西安旅游业的发展提出了相关对策建议。