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1.
In this paper, we discuss the properties of preliminary test estimators (PTE) of the parameters of simple linear model with measurement error (ME model) when the slope of the linear model is suspected to be zero. Expressions of the bias, MSE and efficiencies are obtained under conditional as well as unconditional situations with known reliability coefficient. Conditional model results are compared to the standard model without measurement error. We also provide the unconditional model analysis in finite samples. Asymptotic theory under local alternatives is developed when the variance of measurement error or the ratio of the variance of the model error relative to the variance of the measurement error is known. Asymptotic expressions of bias and MSE of the estimators along with their efficiencies are obtained. In every case, it is shown that the measurement error tend to increase the variability of the estimators compared to the estimators without measurement error. Graphs and tables are provided to see these results and to determine optimum level of significance for minimum guaranteed efficiency. Received October 2001 RID="*" ID="*"  A. K. Md. E. Saleh is a Distinguished Research Professor and H. M. Kim is a Ph.D. candidate in the School of Mathematics and Statistics, Carleton University, Ottawa. Acknowledgment. The authors gratefully acknowledge the constructive suggestion of the referees to improve the paper. The research is supported by NSERC grant A3088.  相似文献   
2.
Sample design and sample allocation methods are developed for random digit dialling in household telephone surveys. The proposed method is based on a two-way stratification of telephone numbers. A weighted probability proportional to size sample allocation technique is used, with auxiliary variables about the telephone coverage rates, within local telephone exchanges of each substrata. This makes the sampling design nearly “self-weighting” in residential numbers when the prior information is well assigned. A computer program generates random numbers for the local areas within the existing phone capacities. A simulation study has shown greater sample allocation gain by the weighted probabilities proportional to size measures over other sample allocation methods. The amount of dialling required to obtain the sample is less than for proportional allocation. A decrease is also observed on the gain in sample allocation for some methods through the increasing sample sizes.  相似文献   
3.
Security of Big Data is a huge concern. In a broad sense, Big Data contains two types of data: structured and unstructured. Providing security to unstructured data is more difficult than providing security to structured data. In this paper, we have developed an approach to provide adequate security to unstructured data by considering types of data and their sensitivity levels. We have reviewed the different analytics methods of Big Data to build nodes of different types of data. Each type of data has been classified to provide adequate security and enhance the overhead of the security system. To provide security to a data node, and a security suite has been designed by incorporating different security algorithms. Those security algorithms collectively form a security suite which has been interfaced with the data node. Information on data sensitivity has been collected through a survey. We have shown through several experiments on multiple computer systems with varied configurations that data classification with respect to sensitivity levels enhances the performance of the system. The experimental results show how and in what amount the designed security suite reduces overhead and increases security simultaneously.  相似文献   
4.
Innovation is the engine of development for enterprises, and there is an increasing trend to adopt an open innovation strategy. However, how to manage external resources in an open, collaborative and complementary manner, and in a shared environment that will yield the greatest networking effects, it is a challenging task. Because there is no such a satisfactory model for an open innovation strategy that combine operational mechanisms with the management of, external resources. Thhis article tries to fill the gap by adopting a resource-based perspective to construct an overall open innovation (OOI) business model. In this model, external resources are classified as industrial and non-industrial entities, to enable the identification of the interaction methods between manufacturing enterprises and external resources. The management of external resources involved in a Technology Open Innovation (TOI) cycle is given particular attention that includes: 1) the classification of the external resources of a TOI, 2) the general mechanisms extracted to promote qualified resources in and unqualified resources out, and 3) a business model to conceptualize the collaboration between enterprises and external resources. A case study of TOI is also provided to empirically verify its feasibility. This paper contributes to the literature by providing an original operational model and mechanism design for an open innovation strategy that is capable of managing external resources effectively.  相似文献   
5.
Bangladesh, a labour-abundant country, is finally learning to reap gains from her labour abundance. The historical under-optimized capital–labour ratio of Bangladesh is slowly moving towards its optimum as the migration of its labour force and consequent inflow of remittance strategically converts its abundant labour into capital. Though the fear that remittance as an alternative source of earning may result in Dutch disease for existing family members; annual data for 1982–2013 and through applying standard testing methodologies, our empirical findings suggest that such a fear is not valid since remittance flow significantly improves domestic labour productivity in Bangladesh in the long run.  相似文献   
6.
The authors examine whether firm corporate governance (CG) contributes to lower stock-return volatility. Using the panel data of 1,252 public listed firms in Asia across 11 countries for 15 years, the authors document international evidence that CG has a stabilizing effect on firm stock-return volatility. The authors further examine whether increasing information efficiency, reducing foreign exposure, and a lower cost of capital contribute to the stabilizing effect of firm CG on stock-return volatility. The result implies that better CG will only reduce stock-return volatility for firms that have less foreign exposure.  相似文献   
7.
Journal of Business Ethics - The purpose of this article is to problematise a particular social transparency and disclosure regulation in the UK, that transcend national boundaries in order to...  相似文献   
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9.
Using data from a nationally representative farm survey in India, we have analyzed Indian farmers' stated preference for farming as a profession. Findings show that more than 40% of farmers dislike farming as a profession because of low profits, high risk, and lack of social status, yet they continue with it owing to a lack of opportunities outside agriculture. Farmers who express a preference for moving out of agriculture are mostly those with small landholdings, poor irrigation facilities, fewer productive assets including livestock, and follow a cereal‐centric cropping pattern. They also have relatively lower access to credit, insurance, and information, and are weakly integrated with social networks such as self‐help groups and farmers' organizations. Importantly, the disinclination for farming, conditional on other covariates, is not significantly differentiated by caste, an important indicator of social status in rural India. Yet, within a caste group, the dislike for farming moderates with larger landholdings.  相似文献   
10.
Participation index: a measure to identify rural transport disadvantage?   总被引:1,自引:0,他引:1  
This paper develops a composite participation index (PI) to identify patterns of transport disadvantage in space and time. It is operationalised using 157 weekly activity-travel diaries data collected from three case study areas in rural Northern Ireland. A review of activity space and travel behaviour research found that six dimensional indicators of activity spaces were typically used including the number of unique locations visited, distance travelled, area of activity spaces, frequency of activity participation, types of activity participated in, and duration of participation in order to identify transport disadvantage. A combined measure using six individual indices were developed based on the six dimensional indicators of activity spaces, by taking into account the relativity of the measures for weekdays, weekends, and for a week. Factor analyses were conducted to derive weights of these indices to form the PI measure. Multivariate analysis using general linear models of the different indicators/indices identified new patterns of transport disadvantage. The research found that: indicator based measures and index based measures are complement each other; interactions between different factors generated new patterns of transport disadvantage; and that these patterns vary in space and time. The analysis also indicates that the transport needs of different disadvantaged groups are varied.  相似文献   
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