Risky Inference: Unobserved Treatment Effects in Conflict Studies

This article illustrates the importance of testing empirical models in samples appropriate to the theories the models are intended to test. While social science appears to mandate that we prefer general theories to limited ones, the generality of a theory rests in its logical application to a set of observations, not solely to its statistical survival in a large data set. Theories in international relations, especially those linking domestic turmoil and international conflict, are advancing, but are sometimes applied to samples larger than the related theories indicate. This paper examines the statistical consequences of estimation in overexpansive samples with unmodeled treatment effects; we argue that samples containing cases that cannot experience the causal phenomenon in question produce unmodeled treatment effects, and we reexamine three published articles whose samples are perhaps broader than their theories suggest they should be. The empirical analyses demonstrate that overexpansive samples can produce somewhat misleading results: the new models produce interesting findings that emerge as treatment effects are identified.     

Welfare gains from optimization in dynamic planning models

This paper compares the results of two multisectoral models used to plan the dynamic consistency of sectoral investment. Solution of an optimizing model forecasts a frontier of the economy's future choice set. This frontier represents a ten year welfare gain only 2 or 3 percent greater than any investment program simulated by a dynamic Leontief system. The paper explains what efficient behavior accounts for the “better” performance of the optimizing model. Developing dynamic programming models is costly in terms of data, computational complexity, man-machine interaction, and solution interpretation. Therefore, it is recommended that the lessons derived by working with the dynamic LP be applied to improve the planner's control of the less expensive input/output simulation model.     

Documents Received

Publications Received

Documents Received     

Potency of delta 9-THC and other cannabinoids in cannabis in England in 2005: implications for psychoactivity and pharmacology

Gas chromatography was used to study the cannabinoid content ("potency") of illicit cannabis seized by police in England in 2004/5. Of the four hundred and fifty two samples, indoor-grown unpollinated female cannabis ("sinsemilla") was the most frequent form, followed by resin (hashish) and imported outdoor-grown herbal cannabis (marijuana). The content of the psychoactive cannabinoid delta 9-tetrahydrocannabinol (THC) varied widely. The median THC content of herbal cannabis and resin was 2.1% and 3.5%, respectively. The median 13.9% THC content of sinsemilla was significantly higher than that recorded in the UK in 1996/8. In sinsemilla and imported herbal cannabis, the content of the antipsychotic cannabinoid cannabidiol (CBD) was extremely low. In resin, however, the average CBD content exceeded that of THC, and the relative proportions of the two cannabinoids varied widely between samples. The increases in average THC content and relative popularity of sinsemilla cannabis, combined with the absence of the anti-psychotic cannabinoid CBD, suggest that the current trends in cannabis use pose an increasing risk to those users susceptible to the harmful psychological effects associated with high doses of THC.     

Bleedings, purges, and vomits: Dr. Benjamin Rush's republican medicine, the bilious remitting yellow-fever epidemic of 1793, and the non-origin of the law of informed consent

To the consternation of many physicians, the modern law of informed consent imposes certain constraints on their actions, not least that they respect patients' decisions to redefine at will the scope of care. The consequences of this transfer of power are often a nuisance and occasionally fatal, but always a reflection of democracy's leveling march: Physicians now take orders rather than give them. However frustrating the modern preference for process over result might be, we should ask ourselves-before condemning the law's evolution-about the consequences for patients' health of a more radically democratic practice of medicine. This paper proposes to examine this question as framed by the life of Dr. Benjamin Rush, who, in addition to signing the Declaration of Independence, crafted a medical practice uniquely suited to the young Republic's presumed moral character: Self-aware sufferers would promptly identify their own maladies and courageously treat themselves. In the end, his enterprise was flawed because his democratic instincts misled not only his scientific inquiries (disease is complex, not simple) but also his practice recommendations (patients are scared, not intrepid). Reflection on Rush's failed project should give pause to those who lament the passing of paternalistic medicine, for the law's requirements, however onerous they might be, tolerably accommodate both patients' need for physicians' expertise and our democratic belief that consent is the fundamental precondition of all rule.