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181.
Organizational power and politics are the central issues of this paper. By developing a model of organizational power it is possible to determine whether an organizational change initiative is likely to be politically feasible. The formal model described has been derived largely from research reported in the social sciences. The modelling process involved using formal methods, in logic and entity relationship analysis, to discover an effective and consistent means of representing key organizational power concepts. The result is an advisory expert system called MP/L1 that can be employed by change agents to predict likely sources of potential resistance to major change initiatives and to suggest tactics that might be effective in combating anticipated resistance. Industrial experience with MP/L1 to date indicates that it has significant potential as a change management tool within the IS strategy-implementation domain. © 1998 John Wiley & Sons, Ltd.  相似文献   
182.
Capital allocation decisions are made on the basis of an assessment of creditworthiness. Default is a rare event for most segments of a bank's portfolio and data information can be minimal. Inference about default rates is essential for efficient capital allocation, for risk management and for compliance with the requirements of the Basel II rules on capital standards for banks. Expert information is crucial in inference about defaults. A Bayesian approach is proposed and illustrated using prior distributions assessed from industry experts. A maximum entropy approach is used to represent expert information. The binomial model, most common in applications, is extended to allow correlated defaults yet remain consistent with Basel II. The application shows that probabilistic information can be elicited from experts and econometric methods can be useful even when data information is sparse. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
183.
184.
Technological innovations have been investigated by means of substitution and diffusion as well as evolution models, each of them dealing with different aspects of the innovation problem. In this paper we follow the well known research traditions on self-organisation models of complex systems. For the first time in the literature we show the existence of a specific niche effect, which may occur in the first stage of establishment of a new technology. Using a stochastic Master equation approach, we obtain analytical expressions for the survival probabilities of a new technology in smaller or larger ensembles. As a main result we demonstrate how a hyperselection situation might be removed in a stochastic picture and thresholds against the prevailing of a new technology in a step-by-step process can be overcome.  相似文献   
185.
We prove a theorem on the existence of rational expectations general economic equilibrium when agents condition on prices as well as on private information, and maximize the expectation of a state-dependent utility function. The key to the result is a new idealization of what it means for a set of empirical distributions to support agents' expectations. This idealization depends on the notion that agents compare their expectations with continuous versions of the random empirical distributions that are generated by the workings of the economy. The existence theorem covers all strictly concave utility functions, arbitrary distributions of the state variable, and situations in which the dimension of the state variable is large relative to the number of commodities.  相似文献   
186.
It has been argued that “paternalistically motivated forced savings constitutes an important, and to some the most important, rationale for social security retirement systems.” This paper revisits the role played by myopia in generating a theoretical rationale for pay-as-you-go (PAYG) social security in dynamically efficient economies. If the competing asset is linear storage and myopic agents are allowed to borrow against future pension benefits, there is no welfare-rationale for PAYG pensions. Sufficiently strong myopia may justify such pensions only if agents cannot borrow against their future pension, but then they are at a zero-saving corner. With enough myopia, co-existence of positive optimal pensions and positive private saving is possible if the return to saving declines with saving, as in a model with a neoclassical technology.  相似文献   
187.
Objective: To assess long-term healthcare costs related to ischemic stroke and systemic embolism (stroke/SE) and major bleeding (MB) events in patients with non-valvular atrial fibrillation (NVAF) treated with non-vitamin K antagonist oral anticoagulants (NOACs).

Materials and methods: Optum’s Clinformatics Data Mart database from 1/2009–12/2016 was analyzed. Adult patients with ≥1 stroke/SE hospitalization (index date) were matched 1:1 to patients without stroke/SE (random index date), based on propensity scores. Patients with an MB event were matched to patients without MB. All patients had an NOAC dispensing overlapping index date, ≥12?months of eligibility pre-index date, and ≥1 NVAF diagnosis. The observation period spanned from the index date until the earliest date of death, switch to warfarin, end of insurance coverage, or end of data availability. Mean costs were evaluated: (1) per-patient-per-year (PPPY) and (2) at 1, 2, 3, and 4?years using Lin's method.

Results: The cost differences were, respectively, $48,807 and $28,298 PPPY for NOAC users with stroke/SE (n?=?1,340) and those with MB (n?=?3,774) events compared to controls. Cost differences of patients with vs without stroke/SE were $49,876, $51,627, $57,822, and $60,691 at 1, 2, 3, and 4?years post-index, respectively (p?p?Limitations: Limitations include unobserved confounders, coding and/or billing inaccuracies, limited sample sizes over longer follow-up, and the under-reporting of mortality for deaths occurring after 2011.

Conclusions: The incremental healthcare costs incurred by patients with vs without stroke/SE was nearly twice as high as those of patients with vs without MB. Moreover, each additional year up to 4?years after the first event was associated with an incremental cost for patients with a stroke/SE or MB event compared to those without an event.  相似文献   
188.
Strategic niche management (SNM), a tool to understand and manage radical socio-technical innovations and facilitate their diffusion, has always departed from a technical artefact. Many radical innovations, however, do not revolve around such an artefact. Social entrepreneurship is a new business model that combines a social goal with a business mentality and is heralded as an important new way to create social value such as sustainability. This study examines if and how SNM can be applied to such a social innovation. It identifies theoretical and practical limitations and proposes solutions. The main conclusion is that SNM can be used to analyse radical social innovation, although it requires rethinking the initial entry point for research and management. Exemplifying quotes are proposed as an alternative. Second, this paper suggests using values to describe niche–regime interaction as a better way to anticipate future niche–regime interactions.  相似文献   
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190.
1871 saw the publication of two major treatises in economics, with self-seeking economic man at their center. In the same year Darwin published The Descent of Man, which emphasized sympathy and cooperation as well as self-interest, and contained a powerful argument that morality has evolved in humans by natural selection. Essentially this stance is supported by modern research. This paper considers the nature of morality and how it has evolved. It reconciles Darwin’s notion that a developed morality requires language and deliberation (and is thus unique to humans), with his other view that moral feelings have a long-evolved and biologically-inherited basis. The social role of morality and its difference with altruism is illustrated by an agent-based simulation. The fact that humans combine both moral and selfish dispositions has major implications for the social sciences and obliges us to abandon the pre-eminent notion of selfish economic man. Economic policy must take account of our moral nature.  相似文献   
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