国产电子分色机横向倍率缩放系统

本文对彩色制版的关键设备——国产电子分色机作了简单介绍。提出了电子分色机的横向倍率缩放功能系统的实现方法及其设计方案,在设计方案中采用了锁相环及PWM脉宽调制器以及其他集成电路。     

动态Nelson-Siegel模型与无套利约束相容吗？——来自中债国债收益率曲线的经验证据

实践上成功的动态Nelson-Siegel利率期限结构模型,存在不能排除无套利机会的理论缺陷,而符合金融理论的无套利仿射模型却在实证绩效上表现不足。通过对两个模型的估计和比较,本文旨在检验动态Nelson-Siegel模型能否在中国国债市场产生与无套利约束相容的收益率曲线。采用中债即期收益率数据的实证研究显示,中国国债市场存在显著的时变性风险价格,确认了期限溢价的存在,但无套利约束并未明显地改善预测绩效。此外,利用模拟收益率数据的检验发现,无套利模型下的载荷参数估计量,在统计上显著不同于来自于动态Nelson-Siegel模型的载荷,即无证据表明中国国债市场的动态Nelson-Siegel收益率曲线与无套利性是相容的。     

A General Theory for Perceptual Indicators of Family Life Quality

The paper presents Foa and Foa's Resource Theory (1974) that was used to develop a self-report, multidimensional measure of family well-being, an indicator of family life quality. Facet theory methods of sentence mapping provided an explicit way to explain how theoretical constructs were translated to operational measures, and a rationale for the use of multidimensional scaling analysis to verify the circular structure of resource classes proposed by the theory. Results of the analyses confirmed the theoretical propositions for a sample of 560 adults and indicated a better fit of the data for women's, compared to the men's model.     

Robust inference for parsimonious model-based clustering

We introduce a robust clustering procedure for parsimonious model-based clustering. The classical mclust framework is robustified through impartial trimming and eigenvalue-ratio constraints (the tclust framework, which is robust but not affine invariant). An advantage of our resulting mtclust approach is that eigenvalue-ratio constraints are not needed for certain model formulations, leading to affine invariant robust parsimonious clustering. We illustrate the approach via simulations and a benchmark real data example. R code for the proposed method is available at https://github.com/afarcome/mtclust.     

Presenting DEA graphically

This paper introduces a methodology that permits presentation of the results of data envelopment analysis (DEA) graphically. A specialized form of multi-dimensional scaling, Co-Plot, enables presentation of the DEA results in a two-dimensional space, hence in a clear, understandable manner. When plotting ratios rather than original data, DEA efficient units can be visualized clearly, as well as their connections to specific variables and/or ratios. Furthermore, Co-Plot can be used in an exploratory data analysis to identify outliers, whose data require additional scrutiny, and potentially inconsequential variables that could be aggregated or removed from the analysis with little effect on the subsequent DEA results.     

一种快速全局运动估计算法

为了对全局运动进行准确快速的估计,在对全局运动估计算法进行研究的基础上,提出了一种快速全局运动估计算法。该算法基于非线性密度估计,采用了六参数的仿射模型。为了提高计算速度,采用了3层金字塔进行多分辨率计算,而且在每层迭代计算中,将基于块的外点去除算法与特征点提取算法相结合,这样既加快了算法的速度,又提高了计算结果的准确性。全局运动估计的实验结果表明,该算法在速度和准确性上具有一定的优势。     

Concept mapping internal validity: A case of misconceived mapping?

Since the early 1990s, the concept mapping technique developed by William M. K. Trochim has been widely used by evaluators for program development and evaluation and proven to be an invaluable tool for evaluators and program planners. The technique combines qualitative and statistical analysis and is designed to help identify and prioritize the components, dimensions, and particularities of a given reality. The aim of this paper is to propose an alternative way of conducting the statistical analysis to make the technique even more useful and the results easier to interpret. We posit that some methodological choices made at the inception stage of the technique were ill informed, producing maps of participants’ points-of-view that were not optimal representations of their reality. Such a depiction resulted from the statistical analysis process by which multidimensional scaling (MDS) is being applied on the similarity matrix, followed by a hierarchical cluster analysis (HCA) on the Euclidian distances between statements as plotted on the resulting two-dimensional MDS map. As an alternative, we suggest that HCA should be performed first and MDS second, rather than the reverse. To support this proposal, we present three levels of argument: 1) a logical argument backed up by expert opinions on this issue; 2) statistical evidence of the superiority of our proposed approach and 3) the results of a social validation experiment.     

Investigating call record data using sequence analysis to inform adaptive survey designs

Researchers have become increasingly interested in better understanding the survey data collection process in interviewer-administered surveys. However, tools for analysing paradata capturing information about field processes, also called call record data, are still not yet fully explored. This paper introduces sequence analysis as a simple tool for investigating such data with the aim of better understanding and improving survey processes. A novel approach is to use sequence analysis within interviewers, which allows the identification of unusual interviewer calling behaviours, and may provide guidance on interviewer performance. Combining the technique with clustering, optimal matching and multidimensional scaling, the method offers a way of visualising, displaying and summarising complex call record data. The method is introduced to inform survey management and survey monitoring. The method is hence informative for adaptive survey designs and will help to identify unusual behaviour and outliers and to improve survey processes. Sequence analysis is applied to call record data from the UK Understanding Society survey. The findings inform further modelling of call record data to increase efficiency in call scheduling.     

Is “Generic Utility Theory” a Suitable Theory of Choice Behavior for Gambles with Mixed Gains and Losses?

Miyamoto's (1988, 1992) generic utility theory (GUT) subsumes a broad class of bilinear utility models. Chechile and Cooke (1997) tested the GUT class of models and found model failure due to the systematic variation of a parameter that should be a positive constant across a range of contexts. In the current study, an improved experimental design is employed to evaluate utility theory. The current study provides further evidence against the GUT class of models for mixed gambles. Moreover, evidence is also provided to demonstrate individual behavior that is incompatible with a coherent bilinear utility theory of choice behavior in the context of mixed gambles with gains and losses.     

Multivariate analysis in genstat

Genstat is a general statistical language for data analysis. The facilities for multivariate and cluster analysis within the language are described as well as the many vector and matrix operations which can be used to form multivariate analysis programs. The contents of the standard macro library relevant to multivariate analysis are also discussed.