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1.
There is increasing evidence that public organizations dedicated exclusively to research and development (R&D) in agribusiness need systematic management tools to incorporate the uncertainties and complexities of technological and nontechnological factors of external environments in its long-term strategic plans. The major issues are: “What will be the agribusiness science and technology (S&T) needs be in the future?” “How to prepare in order to meet these needs?” Both Empresa Brasileira de Pesquisa Agropecuária (Brazilian Agricultural Research Corporation, Embrapa), attached to the Brazilian Ministry of Agriculture and the Agricultural Research Service (ARS) of the US Department of Agriculture (USDA) have developed a comprehensive strategic and operational planning process in order to answer these key questions in the 1990s. The main objective of this article is to present a comparative and preliminary analysis of concepts, methodologies, and processes utilized, and some results obtained by these public organizations.  相似文献   

2.
Nanotechnology has captured wide attention all over the world and excited the imagination of young and old alike. Interest in the subject has increased remarkably during the last few years because of potential technological applications, and commercial interest has skyrocketed. The promise of nanotechnology as an economic engine that can redefine the wellbeing of regions and nations is pervasive; yet the imprecise language, and overuse of the term nanotechnology, has made that term fuzzier, broader, and trendier than many imagined possible. This is especially evident in nanotechnology market projections, which rose dramatically over the past five years as more traditional “product families” were engulfed by the expanding use of the term. Government policy regarding nanotechnology has often resembled an embrace of imagination rather than a systematic use of what Sun Tzu and others have taught about strategic decision making. Further, if nanotechnology is truly the next wave of technology product paradigms, how will we provide an educated workforce to support it? Moreover, in company with these societal benefits come increased societal risks. This paper is intended to provide policy makers and strategists with observations that might limit actions such as those that led to the “over-hype” of nanotechnology and to the fear (or discounting) of societal risks. In the latter case we might learn from the experiences of policy makers connected with other emerging enabling-technology bases, such as nuclear energy and, to a lesser extent, the “dot-com” boom.  相似文献   

3.
A.  B.  K.  V.  A.  P.  I.  S.  E. 《Technological Forecasting and Social Change》2007,74(7):980-1029
We report here spatially explicit scenario interpretations for population and economic activity (GDP) for the time period 1990 to 2100 based on three scenarios (A2, B1, and B2) from the IPCC Special Report on Emissions Scenarios (SRES). At the highest degree of spatial detail, the scenario indicators are calculated at a 0.5 by 0.5 degree resolution. All three scenarios follow the qualitative scenario characteristics, as outlined in the original SRES scenarios. Two scenarios (B1 and B2) also follow (with minor adjustments due to scenario improvements) the original SRES quantifications at the level of 4 and 11 world regions respectively. The quantification of the original SRES A2 scenario has been revised to reflect recent changing perceptions on the demographic outlook of world population growth. In this revised “high population growth” scenario, A2r world population reaches some 12 billion by 2100 (as opposed to some 15 billion in the original SRES A2 scenario) and is characterized by a “delayed fertility transition” that is also mirrored in a delayed (economic) development catch-up, resulting in an initially stagnating and subsequently only very slow reduction in income disparities. The spatially explicit scenario interpretation proceeds via two steps. Through a combination of decomposition and optimization methods, world regional scenario results are first disaggregated to the level of 185 countries. In a subsequent second step, national results are further disaggregated to a grid cell level, taking urbanization and regional (rural–urban) income disparities explicitly into account. A distinguishing feature of the spatially explicit scenario results reported here is that both methodologies, as well as numerical assumptions underlying the “downscaling” exercise, are scenario-dependent, leading to distinctly different spatial patterns of population and economic activities across the three scenarios examined.  相似文献   

4.
This paper develops a simple sequential-move game to characterize the endogeneity of third-party intervention in conflict. We show how a third party's “intervention technology” interacts with the canonical “conflict technologies” of two rival parties in affecting the sub-game perfect Nash equilibrium outcome. From the perspective of deterrence strategy, we find that it is more costly for a third party to support an ally to deter a challenger from attacking (i.e., to maintain peace or acquiescence), as compared to the alternative case when the third party supports the ally to gain a disputed territory by attacking (i.e., to create war), ceteris paribus. However, an optimally intervening third party can be either “peace-making”, “peace-breaking”, or neither depending on the characteristics of the conflict and the stakes the third party holds with each of the rival parties.  相似文献   

5.
Symmetric (3,2) simple games serve as models for anonymous voting systems in which each voter may vote “yes,” abstain, or vote “no,” the outcome is “yes” or “no,” and all voters play interchangeable roles. The extension to symmetric (j,2) simple games, in which each voter chooses from among j ordered levels of approval, also models some natural decision rules, such as pass–fail grading systems. Each such game is determined by the set of (anonymous) minimal winning profiles. This makes it possible to count the possible systems, and the counts suggest some interesting patterns. In the (3,2) case, the approach yields a version of May's Theorem, classifying all possible anonymous voting rules with abstention in terms of quota functions. In contrast to the situation for ordinary simple games these results reveal that the class of simple games with 3 or more levels of approval remains large and varied, even after the imposition of symmetry.  相似文献   

6.
Conditions are investigated under which democratic choice of the division of land between collective and “private” use and of the distribution of collective income between “needs” and “work” payments will produce a Pareto-optimal land allocation and optimal collective labor incentives. Sen's optimal rule for the degree of “needs” distribution is found to result from self-interested voting on this parameter when the distribution of labor inputs is unskewed or when votes are weighted by labor contributions. This in turn increases the optimality of land allocation, which can be further improved by a simple rental scheme. J. Comp. Econ., Dec. 1981, 5(4), pp. 392–403. Brown University, Providence, Rhode Island.  相似文献   

7.
We investigate experimentally whether preferences over an outcome depend on what other possible outcomes of the situation under consideration are, i.e., whether choices are “menu dependent.” In simple sequential games we analyze whether reactions to a certain benchmark outcome are influenced by changes in the payoffs of another outcome, not attainable at that time, called the “reference point.” Our data provide evidence that is favorable to the notion of menu dependence. Alterations of the reference point can lead to quantitatively significant changes in behavior at the benchmark outcome. The behavior we observe can be interpreted in terms of negative reciprocity. Journal of Economic Literature Classification Numbers: C91, C92, C72.  相似文献   

8.
The possibility of introducing time-succession into a type of scenario approach used in futures research is examined, starting from Duperrin and Godet's SMIC-74 method, which deals with sets of nondated binary events and requires as input data the individual probabilities of these events and their time-independent conditional probabilities, taken by pairs. Time succession is then considered successively at two levels: 1)as a means used just to make conditional probabilities more accessible to intuition, following a proposal of Mitchell and Tydeman, to which a simplification is suggested; and 2) as a characteristic to be kept in the time-succession dependent scenarios that are finally dealt with. In the second the investigated period is split into q time “scenes,” as suggested by Olaf Helmer, and a method is proposed using the same algorithm as is used in SMIC-74, but in which binary events, as basic elements, are replaced by “boxed-events.” A boxed-event consists in the couple formed by an event and a “box” that represents either one of the q time scenes or the nonoccurrence of the event. The procedure by which experts can be consulted about the individual and conditional probability data required is described in some detail.  相似文献   

9.
We investigate the problem of simultaneously characterizing various classes of simple games in three different ways: (i) the existence of “quasi-weightings” in which smaller numerical values are assigned to losing coalitions than are assigned to winning ones, (ii) the robustness of “winningness” with respect to trades involving groups of players, and (iii) the acyclicity of certain strict “orderings” that intuitively correspond to the idea of one player being more desirable than another.Journal of Economic LiteratureClassification Number: C71.  相似文献   

10.
Following Shapley [Theory of Measurement of Economic Externalities, Academic Press, New York, 1976], we study the problem of the existence of a Nash Equilibrium (NE) in which each trading post is either active or “legitimately” inactive, and we call it a Shapley NE. We consider an example of an exchange economy, borrowed from Cordella and Gabszewicz [Games Econ. Behav. 22 (1998) 162–169], which satisfies the assumptions of Dubey and Shubik [J. Econ. Theory 17 (1978) 1–20], and we show that the trivial equilibrium, the unique NE of the associated strategic market game, is not “very nice,” in the sense that it is not “legitimately” trivial. This result has the more general implication that, under the Dubey and Shubik's assumptions, a Shapley NE may fail to exist.  相似文献   

11.
Scenarios raise a very remarkable challenge. They are a special category of thought experiments and as such they deal with the domain of the “possible” and “probable”, i.e. with the world of speculation. Nevertheless they are of a crucial practical importance for public policy, management and strategic thinking in general: any premeditated significant action has to be preceded by such a thought experiment that anticipates the possibility of its outcomes and its implications. The question is then, how could speculation have such a crucial epistemic role? What kind of knowledge, if any, do scenarios produce? What is the epistemic role of scenarios? The objective of this article is to discuss the controversial but crucial issue of the epistemic functions of scenarios and to outline several possible approaches to it. The article explores the relevance in this respect of the research that has been already done on thought experiments, de-biasing, deductive arguments and uncertainty—and complexity—coping cognitive devices while indicating the potential contribution of that literature to the further development of the scenario building practice and of the futures methodology.  相似文献   

12.
Science itself can be considered as a “fuzzy system.” In attempting to deal with possible laws of scientific development we formulate a simple, partial model and illustrate its use as a means to control the strategy of investments in science.  相似文献   

13.
We tell of the evolving meaning of the term coordination as used by economists. The paper is based on systematic electronic searches (on “coord,” etc.) of major works and leading journals. The term coordination first emerged in professional economics around 1880, to describe the directed productive concatenation of factors or activities within a firm. Also, transportation economists used the term to describe the concatenation of routes and trips of a transportation system. These usages represent what we term concatenate coordination. The next major development came in the 1930s from several LSE economists (Hayek, Plant, Hutt, and Coase), who extended that concept beyond the eye of any actual coordinator. That is, they wrote of the concatenate coordination of a system of polycentric or spontaneous activities. These various applications of concatenate coordination prevailed until the next major development, namely, Thomas Schelling and game models. Here coordination referred to a mutual meshing of actions. Game theorists developed crisp ideas of coordination games (like “battle of the sexes”), coordination equilibria, convention, and path dependence. This “coordination” was not a refashioning, but rather a distinct concept, one we distinguish as mutual coordination. As game models became more familiar to economists, it was mutual coordination that economists increasingly had in mind when they spoke of “coordination.” Economists switched, so to speak, to a new semantic equilibrium. Now, mutual coordination overshadows the older notion of concatenate coordination. The two senses of coordination are conceptually distinct and correspond neatly to the two dictionary definitions of the verb to coordinate. Both are crucial to economics. We suggest that distinguishing between the two senses can help to clarify “coordination” talk. Also, compared to talk of “efficiency” and “optimality,” concatenate coordination allows for a richer, more humanistic, and more openly aesthetic discussion of social affairs. The narrative is backed up by Excel worksheets that report on systematic content searches of the writings of economics using the worldwide web and, using JSTOR, of Quarterly Journal of Economics, Economic Journal, Journal of Political Economy, American Economic Review, and Economica.  相似文献   

14.
In this article we attempt to uncover some systemic management principles for the better management of complex issues. Taking a pragmatic approach we have expanded the case methodology proposed by John Dewey to the case study of a major crisis. By proposing that crises allow for a better apprehension of complexity, we study the changes which were carried out or not, to this day, after the 1988 Nestucca oil spill that occurred in Canada only three months prior to the Exxon-Valdez disaster. After conducting a linear and systemic analysis of the crisis, we propose that the changes institutionalized thus far spring mostly from what we call “behavioral” and “paradigmatic” learning which are weak for addressing complex issues. Proposing that 15% of the people we have interviewed where able to derive a “systemic learning” from this crisis, we suggest several unlocking strategies that allow these systemic lessons to be institutionalized.  相似文献   

15.
Learning to Learn, Pattern Recognition, and Nash Equilibrium   总被引:1,自引:0,他引:1  
The paper studies a large class of bounded-rationality, probabilistic learning models on strategic-form games. The main assumption is that players “recognize” cyclic patterns in the observed history of play. The main result is convergence with probability one to a fixed pattern of pure strategy Nash equilibria, in a large class of “simple games” in which the pure equilibria are nicely spread along the lattice of the game. We also prove that a necessary condition for convergence of behavior to a mixed strategy Nash equilibrium is that the players consider arbitrarily long histories when forming their predictions.Journal of Economic LiteratureClassification Numbers: C72, D83.  相似文献   

16.
Abreu–Matsushima mechanisms can be applied to a broad class of games to induce any desired outcome as the unique rationalizable outcome. We conduct experiments investigating the performance of such mechanisms in two simple coordination games. In these games one pure-strategy equilibrium is “focal”; we assess the efficacy of Abreu–Matsushima mechanisms for implementing the other pure-strategy equilibrium outcome. Abreu–Matsushima mechanisms induce some choices consistent with the desired outcome, but more choices reflect the focal outcome. Moreover, “strengthening” the mechanism has a perverse effect when the desired outcome is a Pareto-dominated risk-dominated equilibrium.Journal of Economic LiteratureClassification Number: C7.  相似文献   

17.
There are two aspects in today's information revolution that started in the late 1970s. The first is an aspect referred to as “the third industrial revolution,” which triggers the transition to the “21st century system of Industrialization.” The information revolution in this sense brings the creation of new “breakthrough industries (new multimedia industries).” And the second aspect of the information revolution possesses the characteristics of both a technological revolution and a social revolution and brings about the arrival of the third phase of the historical evolutionary process of the modern civilization, which proceeds through three phases, namely “militarization, industrialization, and then informatization.”If the bearers of modern industrialization are a “group of enterprises” that have been engaged in the race in order to gain “wealth” (generalized means of exchange/exploitation power), and if these enterprises' activities have been exercised in the world market where their products have been sold, then it is appropriate to call the bearers of informatization a “group of intelprises.” They will be engaged in the race to gain “wisdom” (generalized means of persuasion/induction power), then stages of their activities can be called a “global intelplace” where “sharables,” that is, information and knowledge, will be disseminated. And now, toward the 21st century, the third phase of modernization, which can be called the “informatization/intelprise formation” or the “wisdom game” (intellectualism), is about to begin.Japan's “ie society (a society based on the ie principle—literally, it means “house” but here it is interpreted as cultural principle for organizing a society), which has been going through the process of evolution on the Japan Archipelago, has developed a network-based organization with little stratification within its infrastructure. In this sense, Japanese society can be characterized as a “network-oriented society” in which intelprises and an intelplace in the broad sense have functioned as the essential components of the society since Middle Ages. In general, an intelplace and intelprises that operate actively within this framework serve as the flexible bases for different types of social relations and institutions, such as states and markets and eventually integrate these into the society to a certain extent. In fact, it took place quite regularly during the modernization “in the narrow sense,” or Westernization of Japanese society after the Meiji Restoration. There exist some problems, however. Some of the characteristics found in Japanese society may become obstacles to activities aimed at the sharing and promotion of information and knowledge in the global intelplace and Japanese participation in the “wisdom game.” Badly needed are serious efforts for Japanese intelprise-formation to reduce these obstacles as much as possible.  相似文献   

18.
In this paper, we modify the Djajić [Djajić, S., 1987. “Government Spending and the Optimal Rates of Consumption and Capital Accumulation,” Canadian Journal of Economics 20, 544–554.] model in such a way that government consumption expenditure provides utility to households via the total stock of government services rather than the government consumption flow alone. By using such a framework, we show that the optimality condition for the public service capital stock is the marginal rate of substitution between public service capital and consumption that equals the intertemporal marginal rate of transformation between the two goods. In addition, we show that the relationship between private consumption and public service capital in a household's utility plays an important role in determining the transitional behavior of relevant variables. We also examine the second-best government consumption expenditure policy. By contrast, in the standard flow specification, e.g., Turnovsky and Brock [Turnovsky, S.J. and Brock, W.A., 1980. “Time Consistency and Optimal Government Policies in Perfect Foresight Equilibrium,” Journal of Public Economics 13, 183–212.], Ihori [Ihori, T., 1990. “Government Spending and Private Consumption,” Canadian Journal of Economics 23, 60–69.], and Turnovsky and Fisher [Turnovsky, S.J. and Fisher, W.H., 1995. “The Composition of Government Expenditure and its Consequences for Macroeconomic Performance,” Journal of Economic Dynamics and Control 19, 747–786.], the second-best government consumption expenditure is decided on the basis that the marginal utility of consumption is equal to the discounted sum of the marginal utility of the government's flow spending.  相似文献   

19.
This note characterizes the impact of adding rare stochastic mutations to an “imitation dynamic,” meaning a process with the properties that absent strategies remain absent, and non-homogeneous states are transient. The resulting system will spend almost all of its time at the absorbing states of the no-mutation process. The work of Freidlin and Wentzell [Random Perturbations of Dynamical Systems, Springer, New York, 1984] and its extensions provide a general algorithm for calculating the limit distribution, but this algorithm can be complicated to apply. This note provides a simpler and more intuitive algorithm. Loosely speaking, in a process with K strategies, it is sufficient to find the invariant distribution of a K×K Markov matrix on the K homogeneous states, where the probability of a transit from “all play i” to “all play j” is the probability of a transition from the state “all agents but 1 play i, 1 plays j” to the state “all play j”.  相似文献   

20.
The games of the title are “Nash” (or Hex), “Milnor” (or Y), “Shapley” (or Projective Plane) and “Gale” (or Bridg-It) all of which were discovered (or re-discovered) in Princeton in 1948–1949. After giving the basic topological connections, I will discuss more recent ramifications related to computational complexity theory. A recurrent theme will be non-constructive proofs, or how we can know something can be done without having the slightest idea of how to do it.  相似文献   

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