1,765 research outputs found
Stochastic Dominance, Entropy and Biodiversity Management
In this paper we develop a model of population dynamics using the Shannon entropy index, a measure of diversity that allows for global and specific population shocks. We model the effects of increasing the number of parcels on biodiversity, varying the number of spatially diverse parcels to capture risk diversification. We discuss the concepts of stochastic dominance as a means of project selection, in order to model biodiversity returns and risks. Using a Monte Carlo simulation we find that stochastic dominance may be a useful theoretical construct for project selections but it is unable to rank every case.
Stochastic Dominance, Entropy and Biodiversity Management
In this paper we develop a model of population dynamics using the Shannon entropy index, a measure of diversity that allows for global and specific population shocks. We model the effects of increasing the number of parcels on biodiversity, varying the number of spatially diverse parcels to capture risk diversification. We discuss the concepts of stochastic dominance as a means of project selection, in order to model biodiversity returns and risks. Using a Monte Carlo simulation we find that stochastic dominance may be a useful theoretical construct for project selections but it is unable to rank every case. Key Words: Stochastic Dominance, Entropy, Biodiversity Management
Acoustic, psychophysical, and neuroimaging measurements of the effectiveness of active cancellation during auditory functional magnetic resonance imaging
Functional magnetic resonance imaging (fMRI) is one of the principal neuroimaging techniques for studying human audition, but it generates an intense background sound which hinders listening performance and confounds measures of the auditory response. This paper reports the perceptual effects of an active noise control (ANC) system that operates in the electromagnetically hostile and physically compact neuroimaging environment to provide significant noise reduction, without interfering with image quality. Cancellation was first evaluated at 600 Hz, corresponding to the dominant peak in the power spectrum of the background sound and at which cancellation is maximally effective. Microphone measurements at the ear demonstrated 35 dB of acoustic attenuation [from 93 to 58 dB sound pressure level (SPL)], while masked detection thresholds improved by 20 dB (from 74 to 54 dB SPL). Considerable perceptual benefits were also obtained across other frequencies, including those corresponding to dips in the spectrum of the background sound. Cancellation also improved the statistical detection of sound-related cortical activation, especially for sounds presented at low intensities. These results confirm that ANC offers substantial benefits for fMRI research
Misperceptions in Intergroup Conflict: Disagreeing About What We Disagree About
Two studies examined misperceptions of disagreement in partisan social conflicts, namely, in the debates over abortion (Study 1) and politics (Study 2). We observed that partisans tend to exaggerate differences of opinion with their adversaries. Further, we found that perceptions of disagreement were more pronounced for values that were central to the perceiver\u27s own ideology than for values that were central to the ideology of the perceiver\u27s adversaries. To the extent that partisans assumed disagreement concerning personally important values, they were also inaccurate in perceiving their adversaries\u27 actual opinions. Discussion focuses on the cognitive mechanisms underlying misperceptions of disagreement and strategies for reducing inter- group conflict
The Need for Advanced Cardiac Life Support Certification for Open-Water Lifeguards at Huntington Beach, CA
The number of people visiting U.S. beaches increased in 2007 to more than 240 million people. This increase in activities does not come without danger. Lifeguards maintain beach safety, but little research is available to assist us in determining appropriate certification levels for lifeguards. The authors analyzed various injuries that occurred in the open-water environment of Huntington Beach, CA. Based on the nature of the injuries, they attempted to determine the level of training lifeguards needed. The vast majority of injuries (99%) were soft-tissue injuries, musculoskeletal injuries, or environmental injuries. It was felt that lifeguards with first-aid and basic-life-support (BLS) -level training were able to handle these injuries adequately and that advanced cardiac life support (ACLS) was not necessary. Injuries that happened at Huntington Beach primarily required lifeguards with first-aid and BLS training. It does not seem necessary that all open-water lifeguards be trained in ACLS
Propofol Waste Reduction in the Operating Room
Propofol is the most wasted intravenous medication used in anesthesia in the operating room (OR) (More, Dabhade, & Ghongane, 2015). Propofol, a sedative anxiolytic, is utilized as a continuous infusion in sedation procedures, or monitored anesthesia care (Nagelhout & Elisha, 2014). Inherent to these infusions is unpredictability in determining the amount of medication needed for the duration of a procedure. This project implemented customized propofol preparation charts consistent with the literature to aid the administering professional in determining the approximate milliliter requirement for the duration of a procedure. The pre-intervention steps consisted of voluntary data collection among anonymous anesthesia professionals in the OR regarding infusion characteristics. Patient weight, a commonly used infusion rate, and the duration of procedure were used in the calculation within customized charts. Post-intervention data collection was conducted in the same manner to capture the impact of the charts. This data was measured simultaneously at a local healthcare system’s main hospital and separate surgery center site, and waste reduction from baseline data was found to be 49% and 60%, respectively. This project was conducted over a four-month period and translates to a potential yearly savings of greater than $15,000 for the healthcare system. A culture of waste reduction leads to savings for anesthesia departments and healthcare organizations as a whole
Local Utility Functions and Local Probability Transformations
The local utility function and the local probability transformation are derived from the benefit function and the distance function
Increasing and Decreasing Risk Aversion for Generalized Preferences
In this paper, concepts of comparative risk aversion are developed for generalized risk averse preferences. These measures are applied to the development of general concepts of increasing and decreasing risk aversion. A range of comparative static results for expected utility theory are generalized and extended
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