Initial Public Offerings of Ballplayers

As a field study of choice under uncertainty, we examine baseball teams' investments in amateur players. Though most prospects fail to deliver any return on their multi-million dollar signing bonuses, returns on the minority who succeed easily offset these losses: the expected annual yield on the median first-round draftee is 33 percent. However, the pattern of returns is inconsistent with market efficiency. Yields are lower for high schoolers than collegians (27 percent vs. 43 percent), lower for pitchers than position players (24 percent vs. 41 percent), decline for later round long-shots, and may be negative under competitive bidding.Market efficiency; Bounded rationality; Prospect theory; Winner’s curse

Water availability and agricultural demand:An assessment framework using global datasets in a data scarce catchment, Rokel-Seli River, Sierra Leone

Study region: The proposed assessment framework is aimed at application in Sub-Saharan Africa, but could also be applied in other hydrologically data scarce regions. The test study site was the Rokel-Seli River catchment, Sierra Leone, West Africa. Study focus: We propose a simple, transferable water assessment framework that allows the use of global climate datasets in the assessment of water availability and crop demand in data scarce catchments. In this study, we apply the assessment framework to the catchment of the Rokel-Seli River in Sierra Leone to investigate the capabilities of global datasets complemented with limited historical data in estimating water resources of a river basin facing rising demands from large scale agricultural water withdrawals. We demonstrate how short term river flow records can be extended using a lumped hydrological model, and then use a crop water demand model to generate irrigation water demands for a large irrigated biofuels scheme abstracting from the river. The results of using several different global datasets to drive the assessment framework are compared and the performance evaluated against observed rain and flow gauge records. New hydrological insights: We find that the hydrological model capably simulates both low and high flows satisfactorily, and that all the input datasets consistently produce similar results for water withdrawal scenarios. The proposed framework is successfully applied to assess the variability of flows available for abstraction against agricultural demand. The assessment framework conclusions are robust despite the different input datasets and calibration scenarios tested, and can be extended to include other global input datasets

Approximate semianalytical solutions for the electromagnetic response of a dipping-sphere interacting with conductive overburden

This paper is © 2019 Society of Exploration Geophysicists. The posting is available free of charge and its use is subject to the SEG terms and conditions: https://seg.org/Terms-of-UseElectromagnetic exploration methods have important applications for geologic mapping and mineral exploration in igneous and metamorphic terranes. In such cases, the earth is often largely resistive and the most important interaction is between a conductor of interest and a shallow, thin, horizontal sheet representing glacial tills and clays or the conductive weathering products of the basement rocks (both of which are here termed the “conductive overburden”). To this end, we have developed a theory from which the step and impulse responses of a sphere interacting with conductive overburden can be quickly and efficiently approximated. The sphere model can also be extended to restrict the currents to flow in a specific orientation (termed the dipping-sphere model). The resulting expressions are called semianalytical because all relevant relations are developed analytically, with the exception of the time-convolution integrals. The overburden is assumed to not be touching the sphere, so there is no galvanic interactions between the bodies. We make use of the dipole sphere in a uniform field and thin sheet approximations; however, expressions could be obtained for a sphere in a dipolar (or nondipolar) field using a similar methodology. We have found that there is no term related to the first zero of the relevant Bessel function in the response of the sphere alone. However, there are terms for all other zeros. A test on a synthetic model shows that the combined sphere-overburden response can be reasonably approximated using the first-order perturbation of the overburden field. Minor discrepancies between the approximate and more elaborate numerical responses are believed to be the result of numerical errors. This means that in practice, the proposed approach consists of evaluating one convolution integral over a sum of exponentials multiplied by a polynomial function. This results in an extremely simple algorithmic implementation that is simple to program and easy to run. The proposed approach also provides a simple method that can be used to validate more complex algorithms. A test on field data obtained at the Reid Mahaffy site in Northern Ontario shows that our approximate method is useful for interpreting electromagnetic data even when the background is thick. We use our approach to obtain a better estimate of the geometry and physical properties of the conductor and evaluate the conductance of the overburden

Combining spatial components and Hilbert transforms to interpret ground-time-domain-electromagnetic data

This paper is © 2019 Society of Exploration Geophysicists. The posting is available free of charge and its use is subject to the SEG terms and conditions: https://seg.org/Terms-of-UseWe have developed a method for displaying or imaging data from a ground-time-domain electromagnetic system and for extracting the geometric parameters of a small conductor. The parameters are determined directly from the data using combinations of the spatial components of the secondary fields and their Hilbert transforms. The position of the target coincides with the peaks of the energy envelope (EE) or the -component of the response. Here, the EE is the square root of the sum of the squares of the three spatial components and their Hilbert transforms, whereas the -component response is an analogous quantity that excludes the Hilbert transform terms. Studies on synthetic models indicate that the -component response is sharper than the EE in most possible target orientations. Once the position of a body has been determined using the peak of the -component response, the dip of the target can be quantified using the ratio of the full-width at half-magnitude (FWHM) of the -component response and the -component Hilbert transform response, which is analogous to the EE but excludes the untransformed quantities. Finally, once all other geometric parameters have been determined, the depth of the target can be evaluated using the FWHM of the -component response. The proposed modeling method was tested over an anomaly acquired at the Coulon field site during an InfiniTEM survey in the Abitibi greenstone belt of Quebec. The extracted geometric parameters were consistent with the available geologic information

Phosphoranyl Radical Fragmentation Reactions Driven by Photoredox Catalysis

Photocatalytic generation of phosphoranyl radicals is fast emerging as an essential method for the generation of diverse and valuable radicals, typically via deoxygenation or desulfurization processes. This Perspective is a comprehensive evaluation of all studies using phosphoranyl radicals as tunable mediators in photoredox catalysis, highlighting how two distinct methods for phosphoranyl radical formation (radical addition and nucleophilic addition) can be used to generate versatile radical intermediates with diverse reactivity profiles

The Elamite Cylinder Seal Corpus, c.3500 - 1000 BC

The ancient region of Elam (southwestern Iran) has produced a significant assemblage of cylinder seals across a considerable chronological span. Unlike the glyptic material from the related and neighbouring region Mesopotamia, the Elamite cylinder seals have not previously been studied in detailed reference to one another, nor has there been an established paradigm of stylistic development articulated. This study addresses this lacuna by compiling all the published cylinder seals from Elam (as defined here, thus incorporating the historical provinces of Khuzistan, Luristan and Fars), from their earliest appearance (c.3500 BC), throughout the era of their typological dominance (over stamp seals, thus this study departs c.1000 BC). This compilation is presented in the Elamite Cylinder Seal Catalogue (Volume II), and is annotated and described through the annunciation of eighteen chronologically defined developmental styles (with another two non-chronological type classifications and four miscellaneous groups). Through the further analysis of this data, including the newly formulated and articulated styles, several facets and problems of Elamite glyptic material have been addressed (and thus the reliance upon assumed similarity in type and function with the Mesopotamian glyptic material is abandoned). These problems particularly pertain to the function of cylinder seals in Elam and the type and form of the Elamite-Mesopotamian glyptic interaction. In regards to function, a standard administrative function can be discerned, though of varying types and forms across the region and the period of study. Other, non-standard, symbolic glyptic functions can also be demonstrated in the Corpus, including the apparent proliferation of a form known as the ‘votive’ seal, perhaps a specifically Elamite form. The analysis of the style type (whether ‘Elamite’, ‘Mesopotamian Related’ or ‘Shared Elamite-Mesopotamian’), in association with their relative geographical and chronological distribution, has also enabled the discussion of the nature of Elamite-Mesopotamian glyptic interaction, and thereby the constitution of Elamite civilisation (especially in regards to Mesopotamian cultural impact and influence, and thus the testing of several previously presented paradigms [Amiet 1979a; 1979b; Miroschedji 2003])

A Hyperbaric Aerodynamic Levitator For Containerless Materials Research

A hyperbaric aerodynamic levitator has been developed for containerless materials research at specimen temperatures exceeding 2000 °C and pressures up to 10.3 MPa (1500 psi). This report describes the prototype instrument design and observations of the influence of specimen size, density, pressure, and flow rate on levitation behavior. The effect of pressure on heat transfer was also assessed by studying the heating and cooling behavior of levitated Al2O3 liquids. A threefold increase in the convective heat transfer coefficient was estimated as pressure increased to 10.3 MPa. The results demonstrate that hyperbaric aerodynamic levitation is a promising technique for containerless materials research at high gas pressures

On ordinal utility, cardinal utility, and random utility

Though the Random Utility Model (RUM) was conceived  entirely in terms of ordinal utility, the apparatus throughwhich it is widely practised exhibits properties of  cardinal utility.  The adoption of cardinal utility as a  working operation of ordinal is perfectly valid, provided  interpretations drawn from that operation remain faithful  to ordinal utility.  The paper considers whether the latterrequirement holds true for several measurements commonly  derived from RUM.  In particular it is found that  measurements of consumer surplus change may depart from  ordinal utility, and exploit the cardinality inherent in  the practical apparatus.

Where Are You From? A Validation of the Foreigner Objectification Scale and the Psychological Correlates of Foreigner Objectification Among Asian Americans and Latinos

Many ethnic minorities in the United States consider themselves to be just as American as their European American counterparts. However, there is a persistent cultural stereotype of ethnic minorities as foreigners (i.e., the perpetual foreigner stereotype) that may be expressed during interpersonal interactions (i.e., foreigner objectification). The goal of the present study was to validate the Foreigner Objectification Scale, a brief self-report measure of perceived foreigner objectification, and to examine the psychological correlates of perceived foreigner objectification. Results indicated that the Foreigner Objectification Scale is structurally (i.e., factor structure) and metrically (i.e., factor loadings) invariant across foreign-born and U.S.-born Asian Americans and Latinos. Scalar (i.e., latent item intercepts) invariance was demonstrated for the two foreign-born groups and the two U.S.-born groups, but not across foreign-born and U.S.-born individuals. Multiple-group structural equation models indicated that, among U.S.-born individuals, perceived foreigner objectification was associated with less life satisfaction and more depressive symptoms, and was indirectly associated with lower self-esteem via identity denial, operationalized as the perception that one is not viewed by others as American. Among foreign-born individuals, perceived foreigner objectification was not significantly associated directly with self-esteem, life satisfaction, or depressive symptoms. However, perceived foreigner objectification was positively associated with identity denial, and identity denial was negatively associated with life satisfaction. This study illustrates the relevance of perceived foreigner objectification to the psychological well-being of U.S.-born Asian Americans and Latinos