Market Power and Efficiency in a Computational Electricity Market with Discriminatory Double-Auction Pricing

This study reports experimental market power and efficiency outcomes for a computational wholesale electricity market operating in the short run under systematically varied concentration and capacity conditions. The pricing of electricity is determined by means of a clearinghouse double auction with discriminatory midpoint pricing. Buyers and sellers use a modifed Roth-Erev individual reinforcement learning algorithm to determine their price and quantity offers in each auction round. It is shown that high market efficiency is generally attained, and that market microstructure is strongly predictive for the relative market power of buyers and sellers independently of the values set for the reinforcement learning parameters. Results are briefly compared against results from an earlier electricity study in which buyers and sellers instead engage in social mimicry learning via genetic algorithms. Related work can be accessed at: http://www.econ.iastate.edu/tesfatsi/AMESMarketHome.htmagent-based computational economics; Wholesale electricity market; restructuring; repeated double auction; market power; efficiency; concentration; capacity; individual reinforcement learning; genetic algorithm social learning

Admiralty- Twilight Zone In Workmen\u27s Compensation - Pursuit of State Common Law Action Against Employer

Petitioner was injured on his employer\u27s barge moored in navigable waters while assisting in a loading operation. The employer was insured solely under the Federal Longshoremen\u27s and Harbor Workers\u27 Act. Instead of pursuing the remedy available under the federal act, petitioner brought the common law action authorized by state workmen\u27s compensation legislation in the state courts. The Oregon Supreme Court affirmed judgment for the employer on the ground that the injury was covered exclusively by the federal act. On certiorari to the United States Supreme Court, held, reversed per curiam, two justices dissenting. The injury was incurred within the twilight zone in which the election of forum by the claimant will be judicially respected. The applicability of the state law is not determined by the scope of the employer\u27s insurance coverage. Hahn v. Ross Island Sand & Gravel Co., 358 U.S. 272 (1959)

Torts - Libel and Slander - Absolute Privilege for Press Release of Lower Federal Officer

Respondents, former employees of the Office of Rent Stabilization, brought a libel action against petitioner, the acting director of the office. The alleged libel was contained in a press release issued by petitioner in which he announced his intention to suspend respondents because of acts for which the office had been severely criticized by the Senate and press. The district court instructed the jury to find for plaintiffs if the release was defamatory. On appeal from judgment for plaintiff, the Court of Appeals for the District of Columbia affirmed. On certiorari, the United States Supreme Court remanded for consideration of the question of qualified privilege. The court of appeals then held that defendant was qualifiedly privileged but remanded to the trial court jury on the question of malice. On certiorari to the United States Supreme Court, held, reversed, four justices dissenting. Petitioner was protected by an absolute privilege in issuing the press release, which was within the scope of his official duties. Barr v. Matteo, 360 U.S. 564 (1959)

A search for starlight reflected from HD 75289 b

We have used a doppler tomographic analysis to conduct a deep search for the starlight reflected from the planetary companion to HD 75289. In 4 nights on VLT2/UVES in January 2003, we obtained 684 high resolution echelle spectra with a total integration time of 26 hours. We establish an upper limit on the planet's geometric albedo p < 0.12 (to the 99.9% significance level) at the most probable orbital inclination i ~ 60 degrees, assuming a grey albedo, a Venus-like phase function and a planetary radius R_p = 1.6 R_Jup. We are able to rule out some combinations of the predicted planetary radius and atmospheric albedo models with high, reflective cloud decks.Comment: 5 pages, 5 figures, MNRAS accepted 12 Oct 200

The Origin of Nitrogen on Jupiter and Saturn from the 15^{15}N/14^{14}N Ratio

The Texas Echelon cross Echelle Spectrograph (TEXES), mounted on NASA's Infrared Telescope Facility (IRTF), was used to map mid-infrared ammonia absorption features on both Jupiter and Saturn in February 2013. Ammonia is the principle reservoir of nitrogen on the giant planets, and the ratio of isotopologues ($^{15}$N/$^{14}$N) can reveal insights into the molecular carrier (e.g., as N$_2$ or NH$_3$) of nitrogen to the forming protoplanets, and hence the source reservoirs from which these worlds accreted. We targeted two spectral intervals (900 and 960 cm$^{-1}$) that were relatively clear of terrestrial atmospheric contamination and contained close features of $^{14}$NH$_3$ and $^{15}$NH$_3$, allowing us to derive the ratio from a single spectrum without ambiguity due to radiometric calibration (the primary source of uncertainty in this study). We present the first ground-based determination of Jupiter's $^{15}$N/$^{14}$N ratio (in the range from $1.4\times10^{-3}$ to $2.5\times10^{-3}$), which is consistent with both previous space-based studies and with the primordial value of the protosolar nebula. On Saturn, we present the first upper limit on the $^{15}$N/$^{14}$N ratio of no larger than $2.0\times10^{-3}$ for the 900-cm$^{-1}$ channel and a less stringent requirement that the ratio be no larger than $2.8\times10^{-3}$ for the 960-cm$^{-1}$ channel ($1\sigma$ confidence). Specifically, the data rule out strong $^{15}$N-enrichments such as those observed in Titan's atmosphere and in cometary nitrogen compounds. To the extent possible with ground-based radiometric uncertainties, the saturnian and jovian $^{15}$N/$^{14}$N ratios appear indistinguishable, implying that $^{15}$N-enriched ammonia ices could not have been a substantial contributor to the bulk nitrogen inventory of either planet, favouring the accretion of primordial N$_2$ from the gas phase or as low-temperature ices.Comment: 33 pages, 19 figures, manuscript accepted for publication in Icaru

Assessing sources and ages of organic matter supporting river and estuarine bacterial production: A multiple-isotope (D14C, d13C, and d15N) approach

We used radiocarbon (D14C) and stable isotopic (d13C, d15N) signatures of bacterial nucleic acids to estimate the sources and ages of organic matter (OM) assimilated by bacteria in the Hudson River and York River estuary. Dualisotope plots of D14C and d13C coupled with a three-source mixing model resolved the major OM sources supporting bacterial biomass production (BBP). However, overlap in the stable isotopic (d13C and d15N) values of potential source end members (i.e., terrestrial, freshwater phytoplankton, and marsh-derived) prohibited unequivocal source assignments for certain samples. In freshwater regions of the York, terrigenous material of relatively recent origin (i.e., decadal in age) accounted for the majority of OM assimilated by bacteria (49–83%). Marsh and freshwater planktonic material made up the other major source of OM, with 5–33% and 6–25% assimilated, respectively. In the mesohaline York, BBP was supported primarily by estuarine phytoplankton–derived OM during spring and summer (53–87%) and by marsh-derived OM during fall (as much as 83%). Isotopic signatures from higher salinity regions of the York suggested that BBP there was fueled predominantly by either estuarine phytoplankton-derived OM (July and November) or by material advected in from the Chesapeake Bay proper (October). In contrast to the York, BBP in the Hudson River estuary was subsidized by a greater portion (up to ;25%) of old (;24,000 yr BP) allochthonous OM, which was presumably derived from soils. These findings collectively suggest that bacterial metabolism and degradation in rivers and estuaries may profoundly alter the mean composition and age of OM during transport within these systems and before its export to the coastal ocean

Prevalence and Correlates of Herbal Medicine Use among Women Seeking Care for Infertility in Freetown, Sierra Leone

© 2018 Peter Bai James et al. In resource-poor countries where access to infertility care is limited, women may turn to traditional medicine to achieve motherhood. It is unknown whether Sierra Leonean women with such condition use herbal medicine. This study investigates the prevalence and factors associated with herbal medicine use among women seeking care for infertility. This was a questionnaire-based cross-sectional study conducted among women seeking care for infertility at various clinics within Freetown, Sierra Leone. Data analysis included Chi-square tests and logistic regression. Out of the 167 women that participated, 36.5% used herbal medicine for infertility treatment. Women with no formal (AOR 4.03, CL: 1.38-11.76, p=0.011), primary education (AOR: 6.23, CL: 2.02-19.23, p=0.001) and those that visited a traditional medicine practitioner (AOR: 20.05, CL: 2.10-192.28, p=0.009) as well as women suffering from other reproductive health problems (AOR: 2.57, CL: 1.13-5.83, p=0.024) were more likely to use herbal medicines. Friends and family (n=57, 96.7%) were the main influencers of herbal medicine use. Only (n=12) 19.7% of users disclosed their status to their healthcare provider. Over half (n=32, 52.5%) could not remember the name of the herb they used. Luffa acutangula (n=29, 100%) was the herbal medicinal plant users could recall. Herbal medicine use among women seeking care for infertility in Freetown is common. Healthcare providers should be aware of the potential dyadic use of herbal and allopathic medicines by their patients and be knowledgeable about commonly used herbal remedies as well as being proactive in communicating the potential risks and benefits associated with their use

The Link between Cognitive Measures and ADLs and IADL Functioning in Mild Alzheimer's: What Has Gender Got to Do with It?

Objectives. To investigate the link between neurocognitive measures and various aspects of daily living (ADL and IADL) in women and men with mild Alzheimer's disease (AD). Methods. Participants were 202 AD patients (91 male, 111 female) with CDR global scores of ≤1. ADLs and IADLs ratings were obtained from caregivers. Cognitive domains were assessed with neuropsychological testing. Results. Memory and executive functioning were related to IADL scores. Executive functioning was linked to total ADL. Comparisons stratified on gender found attention predicted total ADL score in both men and women. Attention predicted bathing and eating ability in women only. Language predicted IADL functions in men (food preparation) and women (driving). Conclusions. Associations between ADLs/IADLs and memory, learning, executive functioning, and language suggest that even in patients with mild AD, basic ADLs require complex cognitive processes. Gender differences in the domains of learning and memory area were found

A framework for automated anomaly detection in high frequency water-quality data from in situ sensors

River water-quality monitoring is increasingly conducted using automated in situ sensors, enabling timelier identification of unexpected values. However, anomalies caused by technical issues confound these data, while the volume and velocity of data prevent manual detection. We present a framework for automated anomaly detection in high-frequency water-quality data from in situ sensors, using turbidity, conductivity and river level data. After identifying end-user needs and defining anomalies, we ranked their importance and selected suitable detection methods. High priority anomalies included sudden isolated spikes and level shifts, most of which were classified correctly by regression-based methods such as autoregressive integrated moving average models. However, using other water-quality variables as covariates reduced performance due to complex relationships among variables. Classification of drift and periods of anomalously low or high variability improved when we applied replaced anomalous measurements with forecasts, but this inflated false positive rates. Feature-based methods also performed well on high priority anomalies, but were also less proficient at detecting lower priority anomalies, resulting in high false negative rates. Unlike regression-based methods, all feature-based methods produced low false positive rates, but did not and require training or optimization. Rule-based methods successfully detected impossible values and missing observations. Thus, we recommend using a combination of methods to improve anomaly detection performance, whilst minimizing false detection rates. Furthermore, our framework emphasizes the importance of communication between end-users and analysts for optimal outcomes with respect to both detection performance and end-user needs. Our framework is applicable to other types of high frequency time-series data and anomaly detection applications

Born-Regulated Gravity in Four Dimensions

Previous work involving Born-regulated gravity theories in two dimensions is extended to four dimensions. The action we consider has two dimensionful parameters. Black hole solutions are studied for typical values of these parameters. For masses above a critical value determined in terms of these parameters, the event horizon persists. For masses below this critical value, the event horizon disappears, leaving a ``bare mass'', though of course no singularity.Comment: LaTeX, 15 pages, 2 figure