Suchergebnisse

Effectiveness in Processes of Science-Policy Interaction -- The Science-Policy Nexus -- Designing Institutions for Science-Policy Interaction -- The Development of an International Regime on a Human-Induced Climate Change -- Structure: The Institutional Design of the Intergovernmental Panel on Climate Change -- Agent: Leadership Performance in the Intergovernmental Panel on Climate Change -- Causal Relationship: Real or Spurious? -- Structure and Agent in the Scientific Diplomacy of Climate Change.

Abstract. Liquefaction-induced hazards such as sand boils, ground cracks, settlement, and lateral spreading are responsible for considerable damage to engineering structures during major earthquakes. Presently, there is no effective empirical approach that can assess different liquefaction-induced hazards in one model. This is because of the uncertainties and complexity of the factors related to seismic liquefaction and liquefaction-induced hazards. In this study, Bayesian networks (BNs) are used to integrate multiple factors related to seismic liquefaction, sand boils, ground cracks, settlement, and lateral spreading into a model based on standard penetration test data. The constructed BN model can assess four different liquefaction-induced hazards together. In a case study, the BN method outperforms an artificial neural network and Ishihara and Yoshimine's simplified method in terms of accuracy, Brier score, recall, precision, and area under the curve (AUC) of the receiver operating characteristic (ROC). This demonstrates that the BN method is a good alternative tool for the risk assessment of liquefaction-induced hazards. Furthermore, the performance of the BN model in estimating liquefaction-induced hazards in Japan's 2011 Tōhoku earthquake confirms its correctness and reliability compared with the liquefaction potential index approach. The proposed BN model can also predict whether the soil becomes liquefied after an earthquake and can deduce the chain reaction process of liquefaction-induced hazards and perform backward reasoning. The assessment results from the proposed model provide informative guidelines for decision-makers to detect the damage state of a field following liquefaction.

Most theoretic models of multiparty electoral competition make the assumption that party leaders are motivated to maximize their vote share or seat share. In plurality-rule systems this is a sensible assumption. However, in proportional representation systems, this assumption is questionable since the ability to make public policy is not strictly increasing in vote shares or seat shares. We present a theoretic model in which party leaders choose electoral declarations with an eye toward the expected policy outcome of the coalition bargaining game induced by the party declarations and the parties' beliefs about citizens' voting behavior. To test this model, we turn to data from the 1989 Dutch parliamentary election. We use Markov chain Monte Carlo methods to estimate the parties' beliefs about mass voting behavior and to average over measurement uncertainty and missing data. Due to the complexity of the parties' objective functions and the uncertainty in objective function estimates, equilibria are found numerically. Unlike previous models of multiparty electoral competition, the equilibrium results are consistent with the empirical declarations of the four major Dutch parties.

In the paper, I propose a project of social coordination as naturalistic social ontology (CNSO) based on the rules-in-equilibria theory of social institutions (Guala and Hindriks 2015; Hindriks and Guala 2015). It takes coordination as the main ontological unit of the social, a mechanism homological across animals and humans, for both can handle coordination problems: in the forms of "animal conventions" and social institutions, respectively. On this account, institutions are correlated equilibria with normative force. However, if both humans and animals solve coordination problems in a similar way, and only humans have social institutions, how do the latter evolve? I suggest identifying possible causes of this evolution among cognitive capacities like mindreading and imitation by building dynamic models. Social ontology becomes constrained by the evolution of the forms of coordination and by the cognitive mechanisms involved in the emergence and persistence of social institutions. It means that it becomes bound to what might be derived from social institutions, i.e., social roles, structures and their derivatives. It shows how conceptual relations might emerge from causal. I conclude the paper with the discussion of the relationship between involved types of explanation, mechanistic and equilibrium ones.

The expanding/contracting behavior of monetary macroeconomic models is largely driven by government deficits. Their monetary effects on inflation and monetary growth determine the real value of money (or of government debt) in the long run. Only positive stationary (constant) real values of money guarantees stationary positive levels of output and employment in the long run. Within a generalized class of nonlinear monetary macroeconomic models of the AS AD type derived from a microeconomic structure with OLG consumers, such economies generically have no stationary equilibria under perfect foresight/rational expectations when tax revenue is income dependent and endogenous (no lump sum taxes) and when the government follows a stationary spending rule. They usually have two balanced stochastic equilibria, an unstable one with positive levels of employment, output, and positive real value of money plus a stable nonmonetary one under hyperinflation (or a monetary bubble). Under the hypothesis of the model, only the stable ones are empirically observable. The paper shows that these properties are true for a large class of AS-AD models including those with a random budget policy rule whose deficit is zero on average. In contrast, such economies have positive stable balanced stationary equilibria if the government policy has a small strictly positive nonrandom demand component in all cases of uncertainty. Among other things, this confirms the long run effectiveness of deficit spending in random economies under rational expectations known from Keynesian theories. The results are derived using techniques from the theory of random dynamical systems which allows a complete theoretical and numerical analysis of the dynamics of random time series and their stability of the nonlinear stochastic model.

We develop a model where banks invest in reserves and loans, and face aggregate liquidity shocks. Banks with liquidity shortage sell loans on the interbank market. Two equilibria emerge. In the no default equilibrium, all banks hold enough reserves and remain solvent. In the mixed equilibrium, some banks default with positive probability. The former exists when credit market competition is intense. The latter emerges when banks exercise market power. Thus, competition is beneficial to financial stability. The structure of liquidity shocks affects the severity and the occurrence of crises, as well as the amount of credit available in the economy.

AbstractWe model oligopolistic firms, producing substitutes, who compete for inputs from capacity constrained suppliers in a decentralized market. Compared to a price‐taking input market, the incentive to foreclose downstream competitors leads to higher input prices and to a higher aggregate amount of input acquired. This novel feature mitigates the output reducing effect of downstream market power and may even restore efficiency in the unique (input) market clearing equilibrium. Other equilibria, where firms coordinate on which suppliers to target, result in excess supply (involuntary unemployment, if input is labor) and even higher input prices. Our insights generalize to alternative vertical structures.

We provide a unified approach to imperfect (monopolistic, Bertrand, and Cournot) competition when preferences are symmetric over a finite but endogenous number of goods. Markups depend on the Morishima elasticity of substitution and on the number of varieties. The comparative statics of free‐entry equilibria is examined, establishing the conditions for markup neutrality with respect to income, market size, and productivity. We compare endogenous and optimal market structures for several non‐CES examples. With a generalized linear direct utility, the markup can be constant and optimal under monopolistic competition, and nonmonotonic in the number of firms under Bertrand or Cournot competition.

A vast theoretical literature explores inefficient market structures in free‐entry equilibria, and previous empirical work demonstrated that excessive entry may obtain in local radio markets. We extend that literature by relaxing the assumption that stations are symmetric, allowing for endogenous horizontal and (unobserved) vertical station differentiation. We find that, in most broadcasting formats, a social planner who takes into account the welfare of market participants eliminates 50%–60% of the observed stations. In 80%–94.9% of markets where high‐quality stations are observed, welfare could be unambiguously improved by converting one such station into low‐quality broadcasting, suggesting local overprovision of quality.

We formally characterize predatory pricing in a modern industry-dynamics framework that endogenizes competitive advantage and industry structure. As an illustrative example we focus on learning-by-doing. To disentangle predatory pricing from mere competition for efficiency on a learning curve we decompose the equilibrium pricing condition. We show that forcing firms to ignore the predatory incentives in setting their prices can have a large impact and that this impact stems from eliminating equilibria with predation-like behavior. Along with the predation-like behavior, however, a fair amount of competition for the market is eliminated. (JEL D21, D43, D83, K21, L13, L41)

ABSTRACTProbabilistic selling has recently been introduced to facilitate consumer segmentation. It allows the retailer to mix products from multiple competing suppliers to generate a probabilistic good. The probabilistic good effectively creates consumer differentiation, and its presence invites extensive interactions among channel participants. In this article, we show that the equilibrium channel structure may be asymmetric: one supplier retains his brand‐name product and the other one delegates to the retailer. We further show that this asymmetric equilibrium can be mutually beneficial for all firms compared with other equilibria. In addition, the introduction of the probabilistic good is beneficial to the channel members.

The Colonel Blotto game captures strategic situations in which players attempt to mismatch an opponent's action. We extend Colonel Blotto to a class of General Blotto games that allow for more general payoffs and externalities between fronts. These extensions make Blotto applicable to a variety of real-world problems. We find that like Colonel Blotto, most General Blotto games do not have pure strategy equilibria. Using a replicator dynamics learning model, we show that General Blotto may have more predictable dynamics than the original Blotto game. Thus, adding realistic structure to Colonel Blotto may, paradoxically, make it less complex. Adapted from the source document.

There are two general ways in which the role of fiat money has been introduced in the standard monetary search‐theoretical model. The first is to bring in the model a fiat object with different intrinsic properties. The second is to introduce a centralized institution that favors the use of fiat money through specific transaction policies. We carry out a similar exercise for a modified version of the model in which agents have a different structure of preferences. We characterize the conditions for which there exist equilibria with circulating fiat money and evaluate the main differences with the results derived from the standard model.

This study examines the economic role of trade protection in a new economic geography model where countries have no inherent differences in endowments, preferences or technologies. This is done in two ways. First, the effects of agricultural and manufacturing protection on the set of equilibria are obtained. Second, the endogenous trade policy positions resulting from a game between national welfare-maximising governments are identified. The model used is a Krugman & Venables (1995) model modified to incorporating agricultural trade costs. Therefore, an additional contribution is the examination of the effect of agricultural trade costs on the equilibrium structure of the model.

Weaker-link & better-shot public goods are prevalent in examples of transnational collective action. Instances include dike building, atmospheric monitoring, cyberspace virus control, deforestation, disease control, & peacekeeping. This paper analyzes essential game-theoretic features of such public goods, which allow correlated strategies to provide Pareto-improving alternatives to the Nash equilibria. Correlation is justified as providing a formal structure for the veil of uncertainty & political leadership. Weaker-link & better-shot public goods differ in terms of the appropriate institutional design. We also consider the consequences of diminishing returns on game forms & institutional prescriptions. 5 Tables, 6 Figures, 1 Appendix, 35 References. Adapted from the source document.