THE BIAS OF COST CONTROL CHARTS TOWARD TYPE II ERRORS

Application of control charts has significantly improved process control by explicitly recognizing uncontrollable variation in the process. A dangerous misapplication of the technique involves the use of control charts with data produced by accounting systems. This paper points out the weaknesses inherent in using aggregated accounting data for inferences about cost control.     

ALTERNATIVES TO EXPECTANCY THEORIES OF WORK MOTIVATION

A number of criticisms of expectancy theory as an explanation of work effort have been raised in recent months. These criticisms are basic enough and based on sound enough evidence to warrant consideration of possible alternate frameworks for the study of work effort. Promising alternatives are: (1) Detuned Cognitive Models; (2) Acognitive Models; and (3) Combined Cognitive and Acognitive Models.     

论停滞与失败--思想意识形态与历史:两个初步的问题(之一)

理学作为一种思想体系受到朝廷的推崇,并作为科举考试的组成部分。在20世纪,对理学的看法发生了分歧。有人认为理学是智识与科学进步的障碍,中国要想走向现代化就必须摆脱理学。关于中国在12世纪后进入长时期停滞的看法,历史学界一般都不赞成了,但读者的这种看法还比较强烈。对于中国历史的一些基本特征的认识需要重新检验,比如中国文化不是只有一个起源;中国并非与外界隔离并拒绝外界影响;中国的政治体制不是绝对独裁;中国文化并没有一个纯正的“正统”或“道统”(orthodox);中国人并非没有自主的完整实体的“自我”观念。学者在实际研究中往往把中国当作一个实体民族或一个连续不断的文明体,这种观念并不太准确,实际是误解了China的原意。     

Solving the part families problem in discrete-parts manufacture by simulated annealing

In the production planning and control of discrete-parts manufacture, aggregation of parts into families, on the basis of similarity, is carried out to ease both long-horizon planning and short-horizon scheduling. Additional advantages are related to those of group technology (GT), such as simplifying the flow of parts and tools and reducing both set-up and production costs. The problem of formally forming part families is presented and discussed. Previous work is reviewed and assessed. Two solution approaches, one based on a location model, the other on simulated annealing, are presented and compared along with test results. The location formulation, which results in an integer programming model solved by Lagrangian relaxation, proved capable of producing solutions of excellent quality, but only for relatively small problem instances. In contrast, simulated annealing, which is a general heuristic approach to combinatorial optimization, produced solutions of comparable quality and could handle realistically large problem instances. However, careful design of the simulated annealing algorithm is crucially important. An effective design is presented.     

Was there compression of disability for older Americans from 1992 to 2003?

Medical advances and the growth of the elderly population have focused interest on trends in the health of the elderly. Three theories have been advanced to describe these trends: compression of morbidity, expansion of morbidity, and dynamic equilibrium. We applied multistate life table methods to the Medicare Current Beneficiary Survey to estimate active and disabled life expectancy from 1992 to 2003, defining disability as having difficulty with instrumental activities of daily living or activities of daily living. We found increases in active life expectancy past age 65 and decreases in life expectancy with severe disability. These trends are consistent with elements of both the theory of compression of morbidity and the theory of dynamic equilibrium.     

Using age and spatial flow structures in the indirect estimation of migration streams

This article outlines a formal model-based approach for inferring interregional age-specific migration streams in settings where such data are incomplete, inadequate, or unavailable. The estimation approach relies heavily on log-linear models, using them to impose some of the regularities exhibited by past age and spatial structures or to combine and borrow information drawn from other sources. The approach is illustrated using data from the 1990 and 2000 U.S. and Mexico censuses.     

Family structure and child outcomes in the USA and Sweden

Previous research shows that living in a non-intact family is associated with educational disadvantages. This paper compares the relationships between childhood family structure, schooling, and earnings in Sweden and the USA. This comparison is interesting because both family structure and public policies differ significantly. We find a negative relationship between living in a non-intact family and child outcomes, and the estimates are remarkably similar in both countries. After using sibling-difference models, the correlation with family structure is no longer significant. These results cast doubt on the causal interpretation of the negative relationship between non-intact family structures and child outcomes.