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911.
The benefits of integrated enterprise-wide information systems (IS), such as Enterprise Resource Planning (ERP) systems, are widely accepted. The implementation of such systems in large organisations is established with many in their second or third generation. However, in small to medium-sized enterprises (SMEs) the maturity and extent of their IS infrastructure is less clear. In engineering SMEs, this infrastructure needs to support not only business processes but also the activities of design and manufacture.In this case study, our goal is to provide a better understanding of current IS infrastructure, the functional elements of IS infrastructure, integration and expenditures are explored in ten engineering SMEs. A model of IS functionality is developed and used to identify and classify functional elements within the firms and to compare and contrast the IS infrastructures. The findings are contrasted with the SME literature and conclusions and implications developed.  相似文献   
912.
Using data from the New Immigrant Survey, we examine the religious beliefs and practices of new legal immigrants to the United States. We find that Christian immigrants are more Catholic, more Orthodox, and less Protestant than American Christians, and that those immigrants who are Protestant are more likely to be evangelical. In addition to being more Catholic and more Orthodox than American Christians, the new immigrants are also paradoxically less Christian, with a fifth reporting some other faith. Detailed analysis of reported church attendance at places of origin and in the United States suggest that immigration is a disruptive event that alienates immigrants from religious practice rather than “theologizing” them. In addition, our models clearly show that people who join congregations in the United States are highly selected and unrepresentative of the broader population of immigrants in any faith. In general, congregational members were more observant both before and after emigration, were more educated, had more cumulative experience in the United States, and were more likely to have children present in the household and be homeowners and therefore yield biased representations of all adherents to any faith. The degree of selectivity and hence bias also varies markedly both by religion and nationality.  相似文献   
913.
Three studies were done to examine the effects of being a tobacco smoker on employment prospects. In Study 1, thirty-two subjects reviewed application forms and rated four applicants as prospective employees. The subjects rated the nonsmoker version of the job applicants significantly more highly for hiring. In Study 2, forty-four subjects stated whether they preferred to hire smokers or nonsmokers and estimated the preference of employers generally. Those who stated a personal preference gave their reasons. Seven personal reasons for preferring a nonsmoker were mentioned by at least two subjects. The reasons ranged from dislike of tobacco smoke to concern about smokers taking more sick leave. In Study 3, which involved forty-six subjects, degree of endorsement of the attitudes underlying four of the seven preference reasons were found to be associated with degree of preference for non-smokers. The results of the three studies provide potentially useful information for job applicants and for individuals who design smoking prevention interventions.  相似文献   
914.
For normal homoscedastic equicorrelated data the parameters μ, σ and p are identifiable, but it is shown that no consistent estimators exist. Confidence intervals for μ and prediction intervals with known confidence coefficients can, however, be obtained.  相似文献   
915.
Modified maximum likelihood estimators of the parameters of a multivariate normal distribution are developed when the smallest or largest observations on one of the components are censored. These estimators are used to construct tests for means and correlation coefficients. The robustness of these tests to deviations from normality is investigated.  相似文献   
916.
In this paper, we consider simple random sampling without replacement from a dichotomous finite population. We investigate accuracy of the Normal approximation to the Hypergeometric probabilities for a wide range of parameter values, including the nonstandard cases where the sampling fraction tends to one and where the proportion of the objects of interest in the population tends to the boundary values, zero and one. We establish a non-uniform Berry–Esseen theorem for the Hypergeometric distribution which shows that in the nonstandard cases, the rate of Normal approximation to the Hypergeometric distribution can be considerably slower than the rate of Normal approximation to the Binomial distribution. We also report results from a moderately large numerical study and provide some guidelines for using the Normal approximation to the Hypergeometric distribution in finite samples.  相似文献   
917.
This paper considers estimation of the parameter of a Poisson distribution using Varian's (1975) asymmetric LINEX loss function L (δ) = b{exp(aδ) - aδ - 1}, where δ is the estimation error and b > 0, a 0. It is shown that for a < 0, the sample mean X¯ is admissible whereas for a > 0, X¯ is dominated by c*X¯, where c*= (n/a)log(1+a/n). Practical implications of this result are indicated. More general results, concerning the admissibility of estimators of the form cX¯+ d are also presented.  相似文献   
918.
Application of the characterization theory to the mixture model   总被引:1,自引:0,他引:1  
This paper indicates the potential application of the characterization theory to the mixture model. It discusses a particular example of a mixture model and concludes that successful application of this theory can be made in order to choose the appropriate mixture model and the mixing parameter.  相似文献   
919.
Ecology of urban lawns under three common management programs   总被引:2,自引:1,他引:1  
Turfgrass lawns are a central part of urban and suburban landscapes throughout North America and are often managed using repeated applications of chemical fertilizers and pesticides. These inputs are expensive and may negatively affect ecological processes in lawns. Therefore, we evaluated the influence of three most common lawn care programs on ecological characteristics of turfgrass lawns. Twenty-eight home lawns, separated into 3 groups based on the lawn care program (professional, do-it-yourself [DIY], and no-input), were studied. Data on lawn quality, weed and insect infestation, disease incidence, soil nematode community, soil nitrogen pools, microbial biomass (MBN), and soil organic matter (SOM) were collected. Results indicated that professional lawn care resulted in the highest aesthetic lawn quality mainly due to better weed control, compared to DIY and no-input programs. However, professional and DIY programs negatively affected MBN and SOM pools and enhanced disease (rust) severity. No significant differences in soil nematode population and nematode community indices across the three programs were found, indicating no differences in net ecosystem productivity among the three programs. Overall, soil nematode food web in turfgrass lawns represented a disturbed food web compared to natural grasslands and forest ecosystems, irrespective of the lawn care program used.  相似文献   
920.
Estimates of variance from samples depend strongly on extreme values. Incomplete variance functions may be used to explain the unreliability of variance estimates when the distribution is long-tailed.  相似文献   
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