The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Peter Turchin - One of the best experts on this subject based on the ideXlab platform.
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Does Population Ecology have general laws
Zhurnal obshchei biologii, 2002Co-Authors: Peter TurchinAbstract:There is a widespread opinion among ecologists that Ecology lacks general laws. In this paper the author argues that this opinion is mistaken. Taking the case of Population dynamics, the author points out that there are several very general law-like propositions that provide the theoretical basis for most Population dynamics models that were developed to address specific issues. Some of these foundational principles, like the law of exponential growth, are logically very similar to certain law of physics (Newton's law of intertia, for example, is almost a direct analogue of exponential growth). The author discusses two other principles (Population self-limitation and resource-consumer oscillations), as well as the more elementary postulates that underlie them. None of the "laws" that the author proposes for Population Ecology are new. Collectively ecologists have been using these general principles in guiding development of their models and experiments since the days of Lotka, Volterra, and Gause.
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Does Population Ecology have general laws
Oikos, 2001Co-Authors: Peter TurchinAbstract:There is a widespread opinion among ecologists that Ecology lacks general laws. In this paper I argue that this opinion is mistaken. Taking the case of Population dynamics, I point out that there are several very general law-like propositions that provide the theoretical basis for most Population dynamics models that were developed to address specific issues. Some of these foundational principles, like the law of exponential growth, are logically very similar to certain laws of physics (Newton's law of inertia, for example, is almost a direct analogue of exponential growth). I discuss two other principles (Population self-limitation and resource-consumer oscillations), as well as the more elementary postulates that underlie them. None of the “laws” that I propose for Population Ecology are new. Collectively ecologists have been using these general principles in guiding development of their models and experiments since the days of Lotka, Volterra, and Gause.
Virginia Gray - One of the best experts on this subject based on the ideXlab platform.
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An Introduction to the Population Ecology Approach
The Organization Ecology of Interest Communities, 2015Co-Authors: David Lowery, Virginia GrayAbstract:For a very long time, the essential traits of Populations of organized interests — their density and diversity — were not considered to be especially interesting. Rather, they were assumed to be simple tallies resulting from mobilization events whereby institutions became active in lobbying or they, along with individual citizens, joined groups or associations that lobbied (Truman 1951; Olson 1965). This changed with the publication of Gray and Lowery’s The Population Ecology of Interest Representation in 1996 (also see: Lowery and Gray 1995). Inspired by core theories of Population biology and organization Ecology, they outlined a theory that both accounted for observed variations in the density and diversity of interest communities in the American states and suggested ways in which these emergent Population characteristics shape organization survival and adaptation, the strategies and tactics interest organizations employ, and how influential these can be in political contexts. Since 1996, the organization Ecology research program has engendered work on all of these topics and has been applied to a wide range of political systems, including the European Union, its member states, and international organizations. In short, we now know that the structure of interest communities matters a great deal.
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the Population Ecology of interest representation lobbying communities in the american states
1996Co-Authors: Virginia Gray, David LoweryAbstract:The importance of Populations -- Conventional research and Population questions -- The Population Ecology approach -- Population Ecology and organized interests -- Describing state interest communities -- Population entry and exit -- The ESA model of Population density -- The ESA model of Population diversity -- The structure of interest communities -- Interest communities and legislative activity -- Impacts on the economy, policy, and politics -- Findings and future work.
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the Population Ecology of gucci gulch or the natural regulation of interest group numbers in the american states
American Journal of Political Science, 1995Co-Authors: David Lowery, Virginia GrayAbstract:Theory: The theory of Population Ecology (in contrast to economic theories of groups) is used to predict the number of interest groups in the United States. Hypotheses: Interest-group density is a function of potential constituents, potential government goods and services, the stability of the political system, government age, and government size. Methods: Regression analysis of U.S. state data for interest groups in construction, agriculture, manufacturing, welfare, the environment, and local governments. Results: Interest group density conforms to the predictions based on Population Ecology (constituents, government goods and services, and political stability), but not those based on economic theories of group mobilization.
Grant Jordan - One of the best experts on this subject based on the ideXlab platform.
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Interpreting Environments: Interest Group Response to Population Ecology Pressures
British Journal of Political Science, 2009Co-Authors: Darren Halpin, Grant JordanAbstract:Important articles in this Journal by Nownes in 2004 and Nownes and Lipinksi in 2005 demonstrate that ‘Population Ecology’ approaches are now central to interest group studies. Partly at least this move to study at Population level is a consequence of the numbers of such organizations. Party scholars typically deal with far fewer cases and sui generis discussion is more defensible. Ecology seems to offer a ‘handle’ on the thousands of cases that exist in the interest group field. Nownes and Lipinski stressed the importance of environmental factors in determining group Populations, and challenged group scholars to address the dynamics among interest group Populations. This article argues that animal-based Population Ecology may be an imperfect analogy to use in making sense of group circumstances. It considers the way groups respond to opportunities and constraints.
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Interpreting Environments: Interest Group Response to Population Ecology Pressures
British Journal of Political Science, 2009Co-Authors: Darren Halpin, Grant JordanAbstract:Important articles in this Journal by Nownes in 2004 and Nownes and Lipinksi in 2005 demonstrate that ‘Population Ecology’ approaches are now central to interest group studies. Partly at least this move to study at Population level is a consequence of the numbers of such organizations. Party scholars typically deal with far fewer cases and sui generis discussion is more defensible. Ecology seems to offer a ‘handle’ on the thousands of cases that exist in the interest group field. Nownes and Lipinski stressed the importance of environmental factors in determining group Populations, and challenged group scholars to address the dynamics among interest group Populations. This article argues that animal-based Population Ecology may be an imperfect analogy to use in making sense of group circumstances. It considers the way groups respond to opportunities and constraints. Pursuing Nownes and Lipinski’s invitation to look at dynamics in particular settings, this article stresses the ‘shaping’ roles of group leaders through an exploration of the way the dominant Scottish farming group mediated the impact of external changes over the past decade. It concludes that while approaches based on Population Ecology rightly emphasize system implications of competition for scarce resources in creating group challenges, the manner in which particular organizations adapt and transform is crucial. Mortality is not inevitable. This article thus builds on those elements within the ecological tradition that accept a place for agency. Ideas such as ‘mortality anxiety’, as used by Gray and Lowery, 1 or ‘survival tactics’, discussed by Imig, 2 show that biological models do not make straightforward metaphors for understanding human-engineered structures.
Stephen H. Levine - One of the best experts on this subject based on the ideXlab platform.
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Products and Ecological Models: A Population Ecology Perspective
Journal of Industrial Ecology, 1999Co-Authors: Stephen H. LevineAbstract:Summary Industrial Ecology has used the systems Ecology model, with its emphasis on the flows of energy and nutrients, as a tool to find ways to minimize the adverse environmental effects of industrial activity. A second ecosystem model, the Population Ecology model, emphasizes intra-and inter-specific interactions of many types. When applied to industrial systems, it suggests an increased focus on products. It therefore can provide a useful complement to the systems Ecology approach. If industrial processes that are less harmful to the environment are to be successfully implemented, they will have to produce products that can successfully penetrate the marketplace. A number of historical examples are used to illustrate the many product interactions discussed.
Zhuang Xu-chun - One of the best experts on this subject based on the ideXlab platform.
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High-speed multicast congestion control based on Population Ecology
Journal of Computer Applications, 2011Co-Authors: Zhuang Xu-chunAbstract:The existing TCP multicast congestion control mechanisms do not have speed smoothness,Round-Trip Time(RTT)-fairness,and high efficiency in high-speed networks.To solve these inherent disadvantages derived from TCP,an Adaptive High-Speed Multicast(AHSM) congestion control mechanism was proposed based on Population Ecology theory.The new mechanism estimated the bottleneck bandwidth and the rate of background traffic at each receiver.Then the estimated values were used in Population Ecology model to calculate requested service rate.The receiver with lowest requested service rate was selected as representative to control the sending rate via feedbacks.The simulation results show that the new mechanism has speed smoothness and RTT-fairness,it also has high transmission efficiency in high-speed networks.It can share bandwidth with unicast flow in both low and high-speed networks.