Interdependent Security: The Case of Identical Agents

Do firms have adequate incentives to invest in anti-terrorism mechanisms? This paper develops a framework for addressing this issue when the security choices by one agent affect the risks faced by others. We utilize the airline security problem to illustrate how the incentive by one airline to invest in baggage checking is affected by the decisions made by others. Specifically if an airline believes that others will not invest in security systems it has much less economic incentive to do so on its own. Private sector mechanisms such as insurance and liability will not necessarily lead to an efficient outcome. To induce adoption of security measures one must turn to regulation, taxation or institutional coordinating mechanisms such as industry associations. We compare the airline security example with problems having a similar structure (i.e., computer security and fire protection) as well as those with different structures (i.e., theft protection and vaccinations). The paper concludes with suggestions for future research.

Necessary and sufficient conditions for a resolution of the social choice paradox

We present a restriction on the domain of individual preferences that is both necessary and sufficient for the existence of a social choice rule that is continuous, anonymous, and respects unanimity. The restriction is that the space of preferences be contractible. Contractibility admits a straightforward intuitive explanation, and is a generalisation of conditions such as single peakedness, value restrictedness and limited agreement, which were earlier shown to be sufficient for majority voting to be an acceptable rule. The only restriction on the number of individuals, is that it be finite and at least 2.social choice; preferences; mathematical modeling

You Only Die Once: Managing Discrete Interdependent Risks

This paper extends our earlier analysis of interdependent security issues to a general class of problems involving discrete interdependent risks with heterogeneous agents. There is a threat of an event that can only happen once, and the risk depends on actions taken by others. Any agent's incentive to invest in managing the risk depends on the actions of others. Security problems at airlines and in computer networks come into this category, as do problems of risk management in organizations facing the possibility of bankruptcy, and individuals' choices about whether to be vaccinated against an infectious disease. Surprisingly the framework also covers certain aspects of investment in R&D. Here we characterize Nash equilibria with heterogeneous agents and give conditions for tipping and cascading of equilibria.

Technology diffusion, abatement cost, and transboundary pollution

This paper studies countries’ incentives to develop advanced pollution abatement technology when technology may spillover across countries and pollution abatement is a global public good. We are motivated in part by the problem of global warming: a solution to this involves providing a global public good, and will surely require the development and implementation of new technologies. We show that at the Nash equilibrium of a simultaneous-move game with R&D investment and emission abatement, whether the free rider effect prevails and under-investment and excess emissions occur depends on the degree of technology spillovers and the effect of R&D on the marginal abatement costs. There are cases in which, contrary to conventional wisdom, Nash equilibrium investments in emissions reductions exceed the first-best case.International environmental agreement; pollution abatement costs; endogenous technological change.

Supermodularity and Tipping

We model tipping as a game-theoretic phenomenon and investigate the connection between supermodular games, tipping of equilibria and cascading, and apply the results to issues that arise in the context of homeland security and computer security. We show that tipping and cascading can occur in supermodular games and that "increasing differences"is a sufficient condition for tipping. Supermodularity and tipping of equilibria are closely related. We relate our results to Schelling%u2019s early work on tipping.

Towards a Matricentric Feminist Poetics

The title of this article recalls that of Elaine Showalter’s essay “Towards a Feminist Poetics,” in which she posits “gynocritics” as a term for a mode of “feminist criticism … concerned with woman as writer—with woman as the producer of textual meaning, with the history, themes, genres and structures of literature by women” (25). Here, I call for a matricentric feminist criticism, or “matricritics,” where the latter refers to that area of literary criticism concerned with the mother as a writer and the attendant subjects. In attempting to draw up a matricritics, I begin by acknowledging the current rise in English-language maternal writing. I then, in the first part of this three-part article, list a number of formal tendencies common to this body of writing, drawing particularly on “Accumulations (Appendix F)” by Kate Zambreno. In the second part, in direct response to this taxonomy, I speculate on and begin to sketch out a critical methodology for reading maternal writing. The third part of the article is given over to a creative matricritical reading of “Appendix F”; this standalone piece is suggestive of how we might conceive of a matricentric feminist reading methodology in practice. An afterword highlights the matricritical elements at work in this alternative close reading

Bundling biodiversity

Biodiversity provides essential services to human societies. Many of these services are provided as public goods, so that they will typically be underprovided both by market mechanisms (because of the impossibility of excluding non-payers from using the services) and by government-run systems (because of the free rider problem). I suggest here that in some cases the public goods provided by biodiversity conservation can be bundled with private goods and their value to consumers captured in the price realized by the private goods. This may lead to an efficient level of provision

Shared decision making between registrars and patients : web based decision aids

BACKGROUND: Current evidence suggests that doctors do not always involve patients in decisions; this may be due to lack of training. This study explores the feasibility of using web based decision aids (DAs) to improve the skills of general practice registrars in sharing decisions with patients. METHOD: Interviews were conducted with registrars to explore their attitudes to shared decision making. Following an educational intervention, registrars were asked to adopt shared decision making within their consultations using DAs as appropriate. The registrars were interviewed again to explore their experiences and any barriers to the process. RESULTS: Registrars had positive views about the shared decision making process but required more training. They had mixed opinions about the use of DAs and identified several barriers to their use. They felt that they had learned from the project and process without necessarily wanting to pursue the use of DAs as interactive tools, preferring to use them as educational resources