11,911 research outputs found

    Employer Defenses to Sexual Harassment Claims

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    Structural Uncertainty and the Value of Statistical Life in the Economics of Catastrophic Climate Change

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    Using climate change as a prototype motivating example, this paper analyzes the implications of structural uncertainty for the economics of low-probability high-impact catastrophes. The paper shows that having an uncertain multiplicative parameter, which scales or amplifies exogenous shocks and is updated by Bayesian learning, induces a critical "tail fattening" of posterior-predictive distributions. These fattened tails can have strong implications for situations (like climate change) where a catastrophe is theoretically possible because prior knowledge cannot place sufficiently narrow bounds on overall damages. The essence of the problem is the difficulty of learning extreme-impact tail behavior from finite data alone. At least potentially, the influence on cost-benefit analysis of fat-tailed uncertainty about the scale of damages -- coupled with a high value of statistical life -- can outweigh the influence of discounting or anything else.

    Neighborhood Preservation in New York City

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    The push to the suburbs, financed in large part by federal mortgage guarantees and highway construction moneys and bolstered by exclusionary zoning, has generated forces which tend to leave old urban neighborhoods in shambles. The syndrome of housing deterioration is well known. The dilemma of the deteriorating neighborhood is heightened in a city such as New York, where a large proportion of its population lives in old multiple family buildings. After almost forty years marked by a succession of programs designed to eliminate slums and blighted areas, New York City has concluded that its older neighborhoods must be protected from the devastation of the deterioration process so that they can be recycled or used by new generations of urban dwellers. On May 23, 1973 the Mayor of the City of New York created the Neighborhood Preservation Program, the first truly comprehensive effort in the nation aimed at preserving sound urban neighborhoods. The purpose of this article is to examine how the program is designed to operate, and analyze how well its objectives have been, and potentially may be, achieved

    Chinese Township Village Enterprises as Vaguely Defined Cooperations

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    This paper concerns the paradoxes and dilemmas that the very successful "Chinese model" presents for transition theory. The "Chinese model" is centered on the development of township-village enterprises. The main purpose of this paper is to make the case that TVE's are not just some form of disguised capitalist institution; they are much better described as "vaguely defined cooperatives" - meaning an essentially communal organization extremely far removed from having well defined ownership structure. That a transition strategy based on vaguely defined cooperatives should be so successful presents a severe challenge for traditional property theory. We speculate that to address this challenge properly, traditional property rights should be extended by including a dimension corresponding to the degree of individualism/cooperation existing in a society. A model of the required extension is described. Implications and application are discussed.

    How Should the Distant Future be Discounted when Discount Rates are Uncertain?

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    It is not immediately clear how to discount distant-future events, like climate change, when the distant-future discount rate itself is uncertain. The so-called “Weitzman-Gollier puzzle” is the fact that two seemingly symmetric and equally plausible ways of dealing with uncertain future discount rates appear to give diametrically opposed results with the opposite policy implications. We explain how the “Weitzman-Gollier puzzle” is resolved. When agents optimize their consumption plans and probabilities are adjusted for risk, the two approaches are identical. What we would wish a reader to take away from this paper is the bottom-line message that the appropriate long run discount rate declines over time toward its lowest possible value.discount rate, term structure, climate change, cost-benefit analysis

    Efficient Gene Targeting Mediated by Adeno-Associated Virus and DNA Double-Strand Breaks

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    Gene targeting is the in situ manipulation of the sequence of an endogenous gene by the introduction of homologous exogenous DNA. Presently, the rate of gene targeting is too low for it to be broadly used in mammalian somatic cell genetics or to cure genetic diseases. Recently, it has been demonstrated that infection with recombinant adeno-associated virus (rAAV) vectors can mediate gene targeting in somatic cells, but the mechanism is unclear. This paper explores the balance between random integration and gene targeting with rAAV. Both random integration and spontaneous gene targeting are dependent on the multiplicity of infection (MOI) of rAAV. It has previously been shown that the introduction of a DNA double-stranded break (DSB) in a target gene can stimulate gene targeting by several-thousand-fold in somatic cells. Creation of a DSB stimulates the frequency of rAAV-mediated gene targeting by over 100-fold, suggesting that the mechanism of rAAV-mediated gene targeting involves, at least in part, the repair of DSBs by homologous recombination. Absolute gene targeting frequencies reach 0.8% with a dual vector system in which one rAAV vector provides a gene targeting substrate and a second vector expresses the nuclease that creates a DSB in the target gene. The frequencies of gene targeting that we achieved with relatively low MOIs suggest that combining rAAV vectors with DSBs is a promising strategy to broaden the application of gene targeting

    Optimal search for the best alternative

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    Prepared under Contract no. EX-76-A-01-2295, Task order 37
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