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1.
This paper presents an analysis of Delphi from a Bayesian point of view and brings to attention several hitherto neglected, but highly relevant findings of research in areas other than Delphi proper. The aim has been to seek avenues of improvement in the Delphi technique. This has led to development of a methodology, which is based on a concept of second order probabilities as a measure of one's fuzzy thinking. The justification of this new methodology lies in explicit recognition and implementation of an optimum, determined by the trade-off between advantages and complexities of hierarchial inference. It is essential that conventional Delphi applications, at the very least, be accompanied by a Turoff-type cross impact analysis. It is indicated that the tremendous potential of Bayesianized Delphi in appropriate situations has remained utapped. 相似文献
2.
Devendra Sahal 《Technological Forecasting and Social Change》1976,8(4):371-384
One of the most common forms of systems analysis is analysis of trade-off. However, few if any studies have been made of longitudinal trade-off, i.e., process of trade-off over time. An understanding of the process of trade-off would seem to be a prerequisite to development of a theory of the evolution of complex systems. In the present study an attempt is made in this direction. An illustrative case of aircraft design process is studied. Three distinct contributions are offered. First, the Pareto distribution is proposed as a relevant asymptotic model of the process of trade-off. Second, the constant parameter (fixed coefficient) assumption in the existing models of the evolution of complex systems is indicated to be a convenience that is not justified by the evidence. Third, the thesis is advanced that in many cases forseeing a breakthrough in systems design and engineering is possible by means of an analysis of residuals in a “properly specified” dimensional analytic framework. More generally, it is suggested that evolution of complex systems is best understood in a dimensional analytic framework. Implications of the results for the actual systems design, R & D project assessment and establishing engineering standards are noted. 相似文献
3.
We develop and validate a measure of tax accrual quality. Tax accrual quality captures variation in the extent to which the income tax accrual maps into income tax-related cash flows, with lower variation indicating a higher quality tax accrual. Low tax accrual quality arises from (1) management estimation error and (2) financial reporting standards that lead to differences between income tax expense and income tax cash flows not captured by deferred tax assets and liabilities. We validate our tax accrual quality measure by showing it is associated with firm characteristics that capture both constructs and by demonstrating it predicts future tax-related restatements and internal control material weaknesses. We illustrate the importance of our measure by showing that investors view tax expense as more informative in firms with better tax accrual quality. Future researchers can use tax accrual quality to address questions related to estimation error in the income tax account. 相似文献
4.
Ali Iftikhar Choudhary Syed Azeem Akhtar Arshad Zaheer 《Journal of Business Ethics》2013,116(2):433-440
The purpose of this study is to examine the impact of two comparative leadership styles on organizational performance outcomes. The leadership styles undertaken is transformational and servant leadership. A sample of 155 participants is taken from profit-oriented service sector of Pakistan. Data through survey gathered on a five point likert scale from organizations. AMOS and SPSS are used for statistical analysis. The result shows that, transformational leadership has more impact on organizational learning than servant leadership. Furthermore organizational learning enhances organizational performance. Managers and leaders of corporate sector can get benefited from this study. Their main objective is to maximize the profitability of organization thus, they can choose leadership style which polishes their abilities and helps them to achieve profit maximization. 相似文献
5.
Nagesh Shukla A.K. Choudhary P.K.S. Prakash K.J. Fernandes M.K. Tiwari 《International Journal of Production Economics》2013,141(1):146-166
The vehicle routing problem with stochastic demand (VRPSD) is a well known NP-hard problem. The uncharacteristic behaviour associated with the problem enhances the computational efforts required to obtain a feasible and near-optimal solution. This paper proposes an algorithm portfolio methodology based on evolutionary algorithms, which takes into account the stochastic nature of customer demand to solve this computationally complex problem. These problems are well known to have computationally complex objective functions, which make their solutions hard to find, particularly when problem instances of large dimensions are considered. Of particular importance in such situations is the timeliness of the solution. For example, Apple was forced to delay their shipments of iPads internationally due to unprecedented demand and issues with their delivery systems in Samsung Electronics and Seiko Epson. Such examples illustrate the importance of stochastic customer demands and the timing of delivery. Moreover, most of the evolutionary algorithms, known for providing computationally efficient solutions, are unable to always provide optimal or near optimal solutions to all the VRPSD instances within allocated time interval. This is due to the characteristic variations in the computational time taken by evolutionary algorithms for same or varying size of the VRPSD instances. Therefore, this paper presents portfolios of different evolutionary algorithms to reduce the computational time taken to resolve the VRPSD. Moreover, an innovative concept of the mobility allowance (MA) in landmoves based on the levy’s distribution function has been introduced to cope with real situations existing in vehicle routing problems. The proposed portfolio approach has been evaluated for the varying instances of the VRPSD. Four of the existing metaheuristics including Genetic Algorithm (GA), Simulated Annealing (SA), Artificial Immune System (AIS), TABU Search (TS) along with new neighbourhood search, are incorporated in the portfolios. Experiments have been performed on varying dimensions of the VRPSD instances to validate the different properties of the algorithm portfolio. An illustrative example is presented to show that the set of metaheuristics allocated to certain number of processors (i.e. algorithm portfolio) performed better than their individual metaheuristics. 相似文献
6.
Devendra Sahal 《Technological Forecasting and Social Change》1976,8(4):385-399
This study is aimed at the development of a theory of the measurement of technology. Several distinct contributions are offered: (1) The existing approaches to the measurement of technological change, including the economic theory of quality change, are concluded to be inappropriate. A statistical version of dimensional analytic theory is presented as an alternative approach and is applied to the illustrative case of aircraft. (2) A dimensional analytic framework is proposed as an alternative to the neoclassical economic conception of the production function. (3) A theory is proposed and substantiated stating that once the basic configuration is established, the evolution of technological systems proceeds in small steps. The role of fundamental knowledge in the process of design appears to be relatively small and fundamental shifts in individual production functions are far less frequent than is commonly believed. (4) It is shown that a dimensional analytic approach transforms the characteristics of different systems to a common domain that also makes comprehensive measurement of intertechnology change a possibility. 相似文献
7.
We consider the problem of component-wise estimation of ordered scale parameters of two gamma populations, when it is known
apriori which population corresponds to each ordered parameter. Under the scale equivariant squared error loss function, smooth
estimators that improve upon the best scale equivariant estimators are derived. These smooth estimators are shown to be generalized
Bayes with respect to a non-informative prior. Finally, using Monte Carlo simulations, these improved smooth estimators are
compared with the best scale equivariant estimators, their non-smooth improvements obtained in Vijayasree, Misra & Singh (1995),
and the restricted maximum likelihood estimators.
Acknowledgments. Authors are thankful to a referee for suggestions leading to improved presentation. 相似文献
8.
In this paper theoretical and empirical models of intra-industry trade are developed in which economic activities, based on measurement and an associated measurement infrastructure, play a role in creating product variety. The paper discusses how the measurement infrastructure which includes institutions conducting metrological research and standard setting organization reduces transactions costs, especially in markets where differences in product characteristics are important. The theoretical analysis focuses on the public good characteristics of the measurement infrastructure, considering how the infrastructure impacts upon trade in a model based upon product differentiation under monopolistic competition. In the econometric analysis, indicators of the strength of the infrastructure within the EU, both across industries and across countries, suggest that measurement activities are important in determining the extent of bi-lateral EU intra-industry trade. Despite many common elements in the measurement infrastructure across the EU, there is also some evidence of differential access to the infrastructure among EU members. 相似文献
9.
Devendra Sahal 《Technological Forecasting and Social Change》1976,9(3):289-300
This paper presents a discriminant analytic framework for the measurement and assessment of technology. It circumvents entirely the problems associated with the other approaches to measurement of technology presented in the literature on technological forecasting and economic theory of quality change. The proposed framework is also capable of providing a whole new variety of systematic approaches to technology assessment. It has been pointed out that the present approach may be regarded as complementary to the dimensional analytical approach presented earlier by the author. In comparison of the two, the notion of process discriminant as distinguished from feature discriminant is advanced. A partial application of the framework to the illustrative case of piston-type aircraft technology is presented. The results of the study provide further support to the hypothesis that the majority of technological change occurs at the level of emperical rather than fundamental knowledge. 相似文献
10.
Devendra Sahal 《Technological Forecasting and Social Change》1985,27(1):1-37
Conventional indicators of technology fail to provide a direct measure of scientific or technological progress. This paper examines three explicit approaches to the measurement of technology: the Hedonic, the Rand, and the composite (wholistic and holistic). Looking at technology from within rather than from without, a theoretical framework for measurement—technometrics—is developed. The state-of-the-art is specified in terms of a surface of constant probability density given the distribution of technological characteristics. The latter, in turn, are specified as vectors in an n-dimensional space. 相似文献