Letting Go of “Natural Kind”: Toward a Multidimensional Framework of Nonarbitrary Classification

This article uses the case study of ethnobiological classification to develop a positive and a negative thesis about the state of natural kind debates. On the one hand, I argue that current accounts of natural kinds can be integrated in a multidimensional framework that advances understanding of classificatory practices in ethnobiology. On the other hand, I argue that such a multidimensional framework does not leave any substantial work for the notion “natural kind” and that attempts to formulate a general account of naturalness have become an obstacle to understanding classificatory practices

Factor analytic reduction of the carotid-cardiac baroreflex parameters

An accepted method for measuring the responsiveness of the carotid-cardiac baroreflex to arterial pressure changes is to artificially stimulate the baroreceptors in the neck. This is accomplished by using a pressurized neck cuff which constricts and distends the carotid artery and subsequently stimulates the baroreceptors. Nine physiological responses to this type of stimulation are quantified and used as indicators of the baroreflex. Thirty male humans between the ages 27 and 46 underwent the carotid-cardiac baroreflex test. The data for the nine response parameters were analyzed by principle component factor analysis. The results of this analysis indicated that 93 percent of the total variance across all nine parameters could be explained in four dimensions. Examination of the factor loadings following an orthogonal rotation of the principle components indicated four well defined dimensions. The first two dimensions reflected location points for R-R interval and carotid distending pressure respectively. The third dimension was composed of measures reflecting the gain of the reflex. The fourth dimension was the ratio of the resting R-R interval to R-R interval during simulated hypertension. The data suggests that the analysis of all nine baroreflex parameters is redundant

Sex, Drugs, and Catholic Schools: Private Schooling and Non-Market Adolescent Behaviors

This paper examines the effects of private schooling on adolescent non-market behaviors. We control for differences between private and public school students by making use of the rich set of covariates available with our NELS micro-dataset. We also employ an instrumental-variables strategy that exploits variation across metropolitan areas in the costs that parents face in transporting their children to private schools, which stem from differences in the quality of the local transportation infrastructure. We find evidence to suggest that religious private schooling reduces teen sexual activity, arrests, and use of hard drugs (cocaine), but not drinking, smoking, gang involvement, or marijuana use.

Dissolution of nucleons in giant nuclei

We discuss the possibility that nuclei with very large baryon numbers can exist in the form of large quark blobs in their ground states. A calculation based on the picture of quark bags shows that, in principle, the appearance of such exotic nuclear states in present laboratory experiments cannot be excluded. Some speculations in connection with the recently observed anomalous positron production in heavy-ion experiments are presented

The Fragility of Short-Term Secured Funding Markets

This paper develops an infinite-horizon model of financial institutions that borrow short-term and invest in long-term assets that can be traded in frictionless markets. Because these financial intermediaries perform maturity transformation, they are subject to potential runs. We derive distinct liquidity, collateral, and asset liquidation constraints, which determine whether a run can occur as a result of changing market expectations. We show that the extent to which borrowers can ward off an individual run depends on whether it has sufficient liquidity, collateral, and asset liquidation capacity. These determinants depend on the borrower’s (endogenous) balance sheet and on (exogenous) fundamentals. Systemic runs are possible if shocks to the valuation of collateral held by outside investors are sufficiently strong and uniform, and if the system as a whole is exposed to high short-term funding risk. The theory has policy implications for prudential regulation and lender-of-last-resort interventions

Long-term analysis of numerical integrators for oscillatory Hamiltonian systems under minimal non-resonance conditions

For trigonometric and modified trigonometric integrators applied to oscillatory Hamiltonian differential equations with one or several constant high frequencies, near-conservation of the total and oscillatory energies are shown over time scales that cover arbitrary negative powers of the step size. This requires non-resonance conditions between the step size and the frequencies, but in contrast to previous results the results do not require any non-resonance conditions among the frequencies. The proof uses modulated Fourier expansions with appropriately modified frequencies.Comment: 26 page

Riding the Yield Curve: Diversification of Strategies

Riding the yield curve, the fixed-income strategy of purchasing a longer-dated security and selling before maturity, has long been a popular means to achieve excess returns compared to buying-and-holding, despite its implicit violations of market efficiency and the pure expectations hypothesis of the term structure. This paper looks at the historic excess returns of different strategies across three countries and proposes several statistical and macro-based trading rules which seem to enhance returns even more. While riding based on the Taylor Rule works well even for longer investment horizons, our empirical results indicate that, using expectations implied by Fed funds futures, excess returns can only be increased over short horizons. Furthermore, we demonstrate that duration-neutral strategies are superior to standard riding on a risk- adjusted basis. Overall, our evidence stands in contrast to the pure expectations hypothesis and points to the existence of risk premia which may be exploited consistently.Term Structure, Interest Rates, Market Efficiency, Taylor Rule

Compte-rendu: Otto Neurath and the Unity of Science

Review of John Symons, Olga Pombo, and Juan Manuel Torres (eds.). 2011. Otto Neurath and the Unity of Science. Dordrecht: Springer

"Letting go of 'Natural Kind'. Towards a Multidimensional Framework of Non-Arbitrary Classification" Philosophy of Science

This article uses the case study of ethnobiological classification to develop a positive and a negative thesis about the state of natural kind debates. On the one hand, I argue that current accounts of natural kinds can be integrated in a multidimensional framework that advances understanding of classificatory practices in ethnobiology. On the other hand, I argue that such a multidimensional framework does not leave any substantial work for the notion ”natural kind” and that attempts to formulate a general account of naturalness have become an obstacle to understanding classificatory practices. In the case of ethnobiology, different accounts of natural kinds pick out different relevant subsets of ethnotaxa but there is nothing to be learnt from the question which subset should qualify as the set of natural kinds

The Role of the Self in Counseling and Its Application to Pastoral Counseling

Recent experimentation has shown that what a person thinks of himself, that is, his self-concept, is very important in his ability to adjust to life\u27s problems. This article will examine the importance which the self-concept plays in counseling and the way in which pastoral counseling will deal with this self-concept. Since the aim of secular counseling (and pastoral counseling to a large extent) is to help the individual adjust to his marital and other situational difficulties, this article will show that the counselor must be concerned with the typical low self-feelings of his counselee and should try to adopt a technique of counseling that will help the person to accept himself more fully and so be better able to adjust