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101.
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The ability of the randomized response technique to obtain sensitiveinformation on surveys was compared to two other methods involvingself-administered questionnaires. Using a national probabilitysample, and extending upon a number of developmental changeswhich have evolved over the years, the randomized response techniqueproved to be decidedly superior to the other methods. 相似文献
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When network effects are important and technology is rapidly improved, this study explores the relative optimality of five product introduction strategies of a durable goods manufacturer: (1) replacement, (2) skipping, (3) a delayed line, (4) shelving, and (5) line‐extension. Using a two‐period analytical model, we show how the type of compatibility—either full or backward compatibility—and the magnitude of the network effect influence the manufacturer's preference for the above strategies. Our analysis reveals that only the strategies (1)–(3) above can be optimal; and the optimal strategy varies with network strength. Further, the type of compatibility can dramatically change the profitability under each optimal strategy; for instance, while backward compatibility can increase the profitability of replacement under certain conditions, it always reduces the profitability of a delayed line. We also illustrate that if compatibility were a choice, although backward compatibility may be observed widely in practice, the parametric region for its optimality is relatively more restricted than that of full compatibility. 相似文献
105.
Sondra S. Teske Mark H. Weir Timothy A. Bartrand Yin Huang Sushil B. Tamrakar Charles N. Haas 《Risk analysis》2014,34(5):911-928
The effect of bioaerosol size was incorporated into predictive dose‐response models for the effects of inhaled aerosols of Francisella tularensis (the causative agent of tularemia) on rhesus monkeys and guinea pigs with bioaerosol diameters ranging between 1.0 and 24 μm. Aerosol‐size‐dependent models were formulated as modification of the exponential and β‐Poisson dose‐response models and model parameters were estimated using maximum likelihood methods and multiple data sets of quantal dose‐response data for which aerosol sizes of inhaled doses were known. Analysis of F. tularensis dose‐response data was best fit by an exponential dose‐response model with a power function including the particle diameter size substituting for the rate parameter k scaling the applied dose. There were differences in the pathogen's aerosol‐size‐dependence equation and models that better represent the observed dose‐response results than the estimate derived from applying the model developed by the International Commission on Radiological Protection (ICRP, 1994) that relies on differential regional lung deposition for human particle exposure. 相似文献
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Based on attachment theory, two aims were addressed. Firstly, we tested whether close teacher–child relationships may buffer children who are less securely attached to their mothers against negative outcomes, such as aggressive behavior. Secondly, our study evaluated whether teacher sensitivity may protect less securely attached children against forming less close relationships with their teachers. In a sample of 127 children, mother–child attachment was observed in preschool. In kindergarten, teacher sensitivity was observed, and teacher–child closeness and child aggressive behavior were rated by the teacher. Results of multilevel hierarchical regression analyses first showed that with high teacher–child closeness, less securely attached children are no longer at risk for more aggressive behavior. Secondly, it was found that with high teacher sensitivity, less securely attached children are no longer at risk for developing less close relationships with their teachers. 相似文献
109.
Jeff Shockley Lawrence A. Plummer Aleda V. Roth Lawrence D. Fredendall 《Production and Operations Management》2015,24(3):451-468
This study uses a service operations management (SOM) strategy lens to investigate chain store retailers' strategic design responsiveness (SDR)—a term that captures the degree to which retailers dynamically coordinate investments in human and structural capital with the complexity of their service and product offerings. Labor force and physical capital are respectively used as proxies for investments in human capital and structural capital, whereas gross margins are proxies for product/service offering complexity. Consequently, SDR broadly reflects three salient complementary choices of SOM design strategy. We test the effects of “brick and mortar” chain store retailers' SDR on current and future firm performance using publically available panel data collected from Compustat and the University of Michigan American Customer Satisfaction Index databases for the period 1996–2011. We find that retailers that fail to keep pace with investments in both structural and human capital exhibit short‐term financial benefits, but have worse ongoing operational performance. These findings corroborate the importance of managers strategically maintaining the complementarity of design‐related choices for improving and maintaining business performance. 相似文献
110.
AbstractThe present study confirms the influential role of a positively and a negatively correlated auxiliary variables in enhancing the precision of estimates of current population mean in two occasion rotation (successive) sampling. Exponential-type estimators of current population mean have been proposed for three different situations: (i) the information on a positively correlated auxiliary variable is readily available on both occasions (ii) the information on a negatively correlated auxiliary variable is readily available on both occasions and (iii) the information on both positively and negatively correlated auxiliary variables are readily available on both the occasions. The characteristics of the proposed estimators have been explored and their efficacious performances are compared with the natural and recent contemporary estimators. Optimum replacement strategies of the proposed estimation procedures have been formulated. Simulation and empirical studies are carried out to justify the proposition of the proposed estimators and appropriate recommendations have been put forward to the survey practitioners. 相似文献