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91.
92.
Paul H. Rubin 《Journal of Bioeconomics》2000,2(1):9-23
Several evolutionary mechanisms have been identified in the literature that would generate altruism in humans. The most powerful (except for kin selection) and most controversial is group selection, as recently analyzed by Sober & D.S. Wilson. I do not take a stand on the issue of the existence of group selection. Instead, I examine the level of human altruism that could exist if group selection were an engine of human evolution. For the Sober & Wilson mechanism to work, groups practicing altruism must grow faster than other groups. I call altruistic behavior that would lead to faster growth efficient altruism. This often consists of cooperation in a prisoner's dilemma. ltruistic acts such as helping a temporarily hungry or injured person would qualify as efficient altruism. Efficient altruism would also require monitoring recipients to avoid shirking. Utilitarianism would be an ethical system consistent with efficient altruism, but Marxism or the Rawlsian system would not. Discussions of efficient altruism also help understand intuitions about fairness. We perceive those behaviors as fair that are consistent with efficient altruism. It is important to understand that, even if humans are selected to be altruistic, the forms of altruism that might exist must be carefully considered and ircumscribed. 相似文献
93.
Paul Heyne 《The Australian economic review》1984,17(3):109-112
94.
A maximum likelihood method to estimate the parameters of dynamic models containing unobserved independent variables is proposed. The approach is to maximize the likelihood of the residuals produced by the recursive Kalman filter equations applied to the model in state-space form. A simulation study is presented comparing the proposed method to the instrumental variable approach. An example using real data is given which estimates models of the Permanent-Income Hypothesis. 相似文献
95.
James Kirkley Catherine J. Morrison Paul Stephen Cunningham Joseph Catanzano 《Environmental and Resource Economics》2004,29(2):191-217
Overfishing and excess capacity in mostfisheries around the world have generated considerableand increasing concern about their biological and economic performance ramifications. Theseproblems, in part, stem from substantialinvestment in technical improvements to boats andequipment in fishing fleets, which exacerbatesexcess fishing capacity and low returns tofishing effort and investment, given regulatoryand biological constraints. However, little attempt hasbeen made to quantify the extent or effects oftechnical change in fisheries. In this paper, we usedetailed data on innovation patterns for 19vessels in the Sète trawl fleet of southernFrance to evaluate the contributions oftechnical change to catch rates. We find thatembodied technical change enhanced productivity by approximately one percent per year between 1985 and 1999, but that external (disembodied) events counteractedthis trend, causing a net output decline ofabout three percent per year. 相似文献
96.
Bruno Miller Author Vitae John-Paul Clarke Author Vitae 《Technological Forecasting and Social Change》2007,74(1):18-35
Air transportation is a key strategic asset in that it provides access to markets and thereby enables the economic development of nations. Thus, in order to maintain their competitiveness in a global economy, countries must invest in air transportation infrastructure to ensure their ability to meet current and future demand for aviation services. The objective of this paper is to develop and illustrate a methodology for evaluating the strategic value of air transportation infrastructure, in particular the benefits associated with the ability to react quickly to changes in the market. The hypothesis is that by recognizing and taking advantage of this strategic value, it may be possible to design better policies for aviation infrastructure delivery.The methodology developed here uses system dynamics to model different strategies for infrastructure delivery. These strategies are defined by three variables: the amount of capacity increase, the time to deliver the capacity and the congestion threshold that triggers the need for capacity delivery. Monte Carlo simulation is used to take into account multiple sources of uncertainty. The model shows that a strategy of capacity delivery based on small increments and short response times can yield more benefits than strategies that consider large capacity increases and long response times. Furthermore, in the specific airport example considered here, it was found that a congestion threshold of 75% should be the trigger for capacity enlargements if strategies based on small capacity increments and 1 or 5 years to increase capacity are considered. The lesson for decision-makers is that congestion delays must be addressed with foresight. 相似文献
97.
Chihiro Watanabe Author Vitae Reiko Kondo Author Vitae Author Vitae Haihong Wei Author Vitae 《Technological Forecasting and Social Change》2004,71(4):365-390
Successful innovation and diffusion of technology can be attributed to the identification of the orbit of emerging new technologies that complement or substitute for existing technologies. This dynamism resembles the co-evolution process in an ecosystem. In an ecosystem, in order to maintain sustainable development, the complex interplay between competition and cooperation, typically observed in predator-prey systems, create a sophisticated balance. Given that an ecosystem can be used as a masterpiece system, this sophisticated balance can provide suggestive ideas for identifying an optimal orbit of competitive innovations with complement or substitution dynamism.Prompted by such a sophisticated balance in an ecosystem, this paper analyzes the optimal orbit of competitive innovations and, on the basis of an application of Lotka-Volterra equations, it reviews substitution orbits of Japan's monochrome to color TV system, fixed telephones to cellular telephones, cellular telephones to mobile Internet access service, and analog to digital TV broadcasting. On the basis of substitution orbits analyses, it attempts to extract suggestions supportive to identifying an optimal policy option in a complex orbit leading to expected orbit.Key findings include policy options that are effective in controlling parameters for Lotka-Volterra equations leading to expected orbit. 相似文献
98.
99.
Yuan-Chieh Chang Author Vitae Ming-Huei Chen Author Vitae Author Vitae Phil Y. Yang Author Vitae 《Technological Forecasting and Social Change》2006,73(2):199-213
Since the passage of the Science and Technology Basic Law in 1999, Taiwanese universities have taken a more “scientific-economic” approach to protect and commercialize their research. This research mainly examines innovation activities such as patenting, licensing, and incubated startups in the context of Taiwanese higher education institutions (HEIs). The “scientific-economic” framework used to analyze the strategic aspects influencing these academic innovations includes (1) intellectual property managerial capabilities, (2) the strength of external industrial partnerships, (3) the university entrepreneurial orientation, and (4) government research policy. Four hypotheses were developed. Data were collected via a questionnaire with all 122 HEIs in Taiwan surveyed.The research reveals that the aspects of intellectual property managerial capability, HEI-industry partnerships, and academic entrepreneurial orientation are useful to distinguish the university's innovation performance on patent grants, licensing incomes, and firm incubation. Also, government support on research plays a moderating role in academic innovation. Managerial and policy implications for managing innovation effectively in universities were drawn. 相似文献
100.
Paul Humphreys George Huang Trevor Cadden Ronan McIvor 《Journal of Purchasing & Supply Management》2007,13(1):42-52
It has been found from the contemporary research in the fields of supply chain management and concurrent engineering that significant benefits can be achieved if suppliers are involved in product development. However, recent investigations in manufacturing industries have revealed that early supplier involvement in the design process is not widely practiced. One issue is the lack of an appropriate customer–supplier interface to assess the suitability of suppliers with reference to design criteria. This paper proposes a mechanism for evaluating supplier involvement during product development. The assessment tool includes four types of distinctive indices to measure supplier involvement in the design process, namely: Satisfaction Index, Flexibility Index, Risk Index, and Confidence Index. These indices measure the extent to which both the customer requirements and the supplier capabilities match or mismatch and therefore reflect the potential or risk of signing a project contract. The proposed methodology is discussed within a multinational telecommunications company and preliminary analysis indicates that the approach provides an effective mechanism for selecting suppliers involved in the product development process. 相似文献