利用生产停顿机会进行维修以提高产量

介绍Statoil公司提出的机会维修概念和它对生产所起的重要作用,举例说明机会维修的可行性,并对机会维修进行优化使它更好地为生产服务.     

Marketing online banking services: The voice of the customer

US banks have invested heavily in developing online capabilities, with the expectation of migrating customers to the new cheaper delivery system. Results in the USA thus far have been mixed at best; market penetration is low and customer usage is sporadic, focusing mainly on simple tasks. This paper reports on the first of two studies conducted to investigate the reasons for the mediocre performance. A qualitative consumer study revealed significant differences in attitudes and opinions between early users and those that banks hope will adopt next. Most importantly, future prospects could be characterised as indifferent about online banking; many were not convinced about its benefits and the value it provides. While the potential to expand the market for online banking services exists, banks need to re-examine their marketing approach.     

Media use and life satisfaction: the moderating role of social events

This study investigates whether and how social events, which have specific impact levels and consequences, influence the relationships between the use of different types of media and media users’ life satisfaction. The impact levels refer to the number of impact factors, which characterize social events (relevance, non-polarization, certainty, radicalness and proximity). The consequences, in turn, refer to the outcomes for media users (positive or negative outcomes). The results are based on data from the Standard Eurobarometer survey (N = 73,860) as well as on data from a content analysis and cover 36 social events in 13 European countries over a time period of 6 years. The moderated moderation analysis reveals that social events only influence the effects of the use of more interactive media types (the internet and social network sites) on media users’ life satisfaction, but they don’t influence the effects of the use of less interactive media types (written press, radio and TV) on media users’ life satisfaction. In fact, social events with positive consequences increase these effects, while social events with negative consequences buffer these effects. Previous research has investigated how the use of different types of media or specific social events affect people’s life satisfaction. This study contributes to the literature by revealing how social events and media use interact and thereby influence media users’ life satisfaction.     

Influence measures on profile analysis with elliptical data through Frèchet’s metric

In this paper, from Frèchet’s metric, diagnostic tools are constructed for the detection of influential observations in Profile Analysis with elliptically distributed random errors . This distributional hypothesis allows the application of the proposed diagnostics to a wide variety of random experiences, not only for data from a multivariate normal distribution but also from other symmetric distributions, commonly used in studies of several sciences. The diagnostics are based on Frèchet’s distance between the distributions of the basic statistics in Profile Analysis, in the postulated model and in the perturbed model obtained by deleting an observation from the sample data. This metric is highly useful since it enables the analysis of the influence on the point estimation and the estimation error. Applications on two data sets are provided.     

On the discrete mean past lifetime

Let T denote a positive discrete survival time and n a non-negative integer number. Properties of the mean past lifetime E(n  −  T|T  <  n) are provided. M. Asadi’s work is supported by the University of Isfahan Grant 850713.     

A product Pareto distribution

The Pareto distributions are becoming increasing prominent in several applied areas. In this note, a new Pareto distribution is introduced. It takes the form of the product of two Pareto probability density functions. Various structural properties of this distribution are derived, including its cumulative distribution function, moments, mean deviation about the mean, mean deviation about the median, entropy, asymptotic distribution of the extreme order statistics, method of moments estimates, maximum likelihood estimates and the Fisher information matrix. The calculations involve the use of several special functions.     

Estimators for the common principal components model based on reweighting: influence functions and Monte Carlo study

The common principal components model for several groups of multivariate observations is a useful parsimonious model for the scatter structure which assumes equal principal axes but different variances along those axes for each group. Due to the lack of resistance of the classical maximum likelihood estimators for the parameters of this model, several robust estimators have been proposed in the literature: plug-in estimators and projection-pursuit (PP) type estimators. In this paper, we show that it is possible to improve the low efficiency of the projection-pursuit estimators by applying a reweighting step. More precisely, we consider plug-in estimators obtained by plugging a reweighted estimator of the scatter matrices into the maximum likelihood equations defining the principal axes. The weights considered penalize observations with large values of the influence measures defined by Boente et al. (2002). The new estimators are studied in terms of theoretical properties (influence functions and asymptotic variances) and are compared with other existing estimators in a simulation study.     

Transferability and Naturalistic Generalization: New Generalizability Concepts for Social Science or Old Wine in New Bottles?

Interpretative qualitative social science has attempted to distinguish itself from quantitative social science by rejecting traditional or ‘received’ notions of generalization. Traditional concepts of scientific generalization it is claimed are based on a misguided objectivism as to the mechanisms operating in the social world, and particularly the ability of statements to capture such mechanisms in any abstract sense. Instead they propose new versions of the generalizability concept e.g. ‘transferability’, which relies on the context dependent judgement of ‘fit’ between two or more cases instances made by a researcher. This paper argues that the transferability concept, as outlined and argued by interpretativist methodologists, is thoroughly coextensive with notions of generalizability formalized for natural science and naturalistic social science by philosophers and methodologists of science. Therefore, it may be concluded that the interpretativist claim to a break with received scientific traditions is a premature one, at least with regard to the issue of generalization.     

Wither Qualitative/Quantitative?: Grounds for Methodological Convergence

The qualitative quantitative issue has been given attention in sociological scholarship for decades. Upon theoretical examination of the basis of separations, the commonly used criteria of subjectivity versus objectivity, systematization, quantification and generalization, do not separate. This suggests that the impetus for the qualitative/quantitative issue is more political than intellectual owing to several factors in the practice of sociology: diverse intellectual heritages, the domination of quantitative sociologists in teaching methods and writing methods text books, the proliferation of computer technology in the past 20 years, and separation of theory and method. Advancing sociological methods means transcending the quantitative/qualitative issue and moving on to consider issues like science, validity, causality and multiverse.