8,249 research outputs found

    Expenditures and Postsecondary Graduation: An Investigation Using Individual-Level Data from the State of Ohio

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    Using detailed individual-level data from public universities in the state of Ohio, I estimate the effect of various institutional expenditures on the probability of graduating from college. Using a competing risks regression framework, I find differential impacts of expenditure categories across student characteristics. I estimate that student service expenditures have a larger impact on students with low SAT/ACT scores, while instructional expenditures are more important for high test score students and those majoring in scientific/quantitative fields. The individual-level nature of these data allows me to address measurement error and endogeneity concerns the previous literature has been unable to deal with

    Newton's Gravity Law and Import Prices in the Asia Pacific

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    exchange rates, import prices, Asia Pacific

    Do Expenditures Other Than Instructional Expenditures Affect Graduation and Persistence Rates in American Higher Education

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    [Excerpt] Rates of tuition increases in both private and public higher education that continually exceed inflation, coupled with the fact that the United States no longer leads the world in terms of the fraction of our young adults who have college degrees, have focused attention on why costs keep increasing in higher education and what categories of higher education expenditures have been growing the most rapidly. In a series of publications, the Delta Cost Project has shown that during the last two decades median instructional spending per full-time equivalent (FTE) student in both public and private 4-year colleges and universities in the United States grew at a slower rate than median expenditures per FTE student in many other categories of expenditures (research, public service, academic support, student services, and scholarships and fellowships).1 Similarly, the Center for College Affordability and Productivity reports that during the same time period, managerial and support/service staff at colleges and universities grew relative to faculty. Do such changes reflect increased inefficiency and waste or do some non instructional categories of employees and expenditures contribute directly to the educational mission of American colleges and universities? In this paper, we use institutional level panel data and an educational production function approach to estimate whether various non instructional categories of expenditures directly influence graduation and persistence rates of undergraduate students in American colleges and universities. We find, not surprisingly, that the answer is several of these expenditure categories do influence students’ educational outcome, but that the extent that they matter varies with the socioeconomic backgrounds and the average test scores of the students attending the institutions

    Temporal variations of the anomalous oxygen component

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    Data from the cosmic ray experiment on Voyagers 1 and 2 was used to examine anomalous oxygen in the time period from launch in 1977 to the end of 1981. Several time periods were found where large periodic (typically 26 day) temporal variations of the oxygen intensity between approximately 5 - 15 MeV/nuc are present. Variations in intensity by up to a factor of 10 are observed during these periods. Several characteristics of these variations indicate that they are not higher energy extensions of the low energy particle (approximately 1 MeV/nuc) increases found in many corotating interaction regions (CIR's). Many of these periodic temporal variations are correlated with similar, but much smaller, recurrent variations in the 75 MeV proton rate. Voyager 1 and Voyager 2 counting rates were compared to estimate the local radial gradient for both the protons and the oxygen. The proton gradients during periods of both maximum and minumum fluxes are consistent with the overall positive radial gradients reported by others from Pioneer and near-Earth observations, supporting the view that these variations are due to local modulation of a source outside the radial range of project measurements. In contrast, the oxygen gradients during periods of maximum proton flux differ in sign from those during minimum proton fluxes, suggesting that the origin of the oxygen variations is different from that of the protons

    Voyager measurements of the energy spectrum, charge composition, and long term temporal variations of the anomalous components in 1977-1982

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    The large collecting area and wide energy range of the cosmic ray experiment on Voyager 1 and 2 was used to examine the energy spectra, charge composition, and long term temporal variations of the anomalous components in 1977-1982. Individual energy spectra are obtained for 17 separate quiet time periods during the time interval. The composite spectra of anomalous He, N, O, and Ne are obtained to a new level of precision. This includes the spectral shape and the relative abundance. Essentially, the spectral shape of N, O, and Ne appear to be similar. The ratios of anomalous N and Ne to O are found to be different from both the solar cosmic ray and galactic cosmic ray source composition. Some evidence is found for the enhancement of Ar as well. In the case of elements such as C, Mg, S, and Fe it is difficult to separate a possible lower intensity anomalous component from a quasi-steady interplanetary component that appears to be present at the lowest energies. The long term temporal variations of the anomalous He and O components were studied from 1977-82, a period from minimum to maximum in the modulation cycle. The tracking between these anomalous component intensities and the integral intensity of 75 MeV protons is striking; however, the intensity decrease of the anomalous components is much greater

    Function of Fast Reflexion in Bipolar choice

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    Our view of "reflexion" has been essentially broadened during the last twenty years. Traditionally we have considered it to consist of the conscious constructing of images of the self and others by human beings. Now we have evidence that there is a reflexion of another nature as well. It is as if an inborn informational processor is built in into human psyche whose function is to automatically create these images together with their subjective domains. This processor generates a specific specter of human responses not controlled consciously and running extremely fast (one-two milliseconds). This type of reflexion,as distinct from the traditional concept, is called fast reflexion (Lefebvre, 1987). In this paper we will decipher the mathematical laws governing the automatic functioning of this inborn processor and show how they reveal themselves in human behavior (Adams-Webber, 1996a). The result of this analysis will be a formal model of the subject with fast reflexio

    The cosmic ray interplanetary radial gradient from 1972 - 1985

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    It is now established that the solar modulation of cosmic rays is produced by turbulent magnetic fields propagated outward by the solar wind. Changes in cosmic ray intensity are not simultaneous throughout the modulation region, thus requiring time dependent theories for the cosmic ray modulation. Fundamental to an overall understanding of this observed time dependent cosmic ray modulation is the behavior of the radial intensity gradient with time and heliocentric distance over the course of a solar modulation cycle. The period from 1977 to 1985 when data are available from the cosmic ray telescopes on Pioneer (P) 10, Voyager (V) 1 and 2, and IMP 8 spacecraft is studied. Additional data from P10 and other IMP satellites for 1972 to 1977 can be used to determine the gradient at the minimum in the solar modulation cycle and as a function of heliocentric distance. All of these telescopes have thresholds for protons and helium nuclei of E 60 MeV/nucleon

    Do Expenditures Other Than Instructional Expenditures Affect Graduation and Persistence Rates in American Higher Education?

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    Median instructional spending per full-time equivalent (FTE) student at American colleges and universities has grown at a slower rate the median spending per FTE in a number of other expenditure categories during the last two decades. We use institutional level panel data and a variety of econometric approaches, including unconditional quantile regression models, to analyze whether noninstructional expenditure categories influence first year persistence and graduation rates of American undergraduate students. Our most important finding is that student service expenditures influence graduation and persistence rates and their marginal effects are larger for students at institutions with lower entrance test scores and more lower income students. Put another way, their effects are largest at institutions that have lower current persistence and graduation rates. Simulations suggest that reallocating some funding from instruction to student services may enhance persistence and graduation rates at those institutions whose rates are currently below the medians in the sample.higher education, productivity, graduation rates

    Can switching fuels save water? A life cycle quantification of freshwater consumption for Texas coal-and natural gas-fired electricity

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    Thermal electricity generation is a major consumer of freshwater for cooling, fuel extraction and air emissions controls, but the life cycle water impacts of different fossil fuel cycles are not well understood. Much of the existing literature relies on decades-old estimates for water intensity, particularly regarding water consumed for fuel extraction. This work uses contemporary data from specific resource basins and power plants in Texas to evaluate water intensity at three major stages of coal and natural gas fuel cycles: fuel extraction, power plant cooling and power plant emissions controls. In particular, the water intensity of fuel extraction is quantified for Texas lignite, conventional natural gas and 11 unconventional natural gas basins in Texas, including major second-order impacts associated with multi-stage hydraulic fracturing. Despite the rise of this water-intensive natural gas extraction method, natural gas extraction appears to consume less freshwater than coal per unit of energy extracted in Texas because of the high water intensity of Texas lignite extraction. This work uses new resource basin and power plant level water intensity data to estimate the potential effects of coal to natural gas fuel switching in Texas’ power sector, a shift under consideration due to potential environmental benefits and very low natural gas prices. Replacing Texas’ coal-fired power plants with natural gas combined cycle plants (NGCCs) would reduce annual freshwater consumption in the state by an estimated 53 billion gallons per year, or 60% of Texas coal power’s water footprint, largely due to the higher efficiency of NGCCs.Mechanical Engineerin

    p, He, and C to Fe cosmic-ray primary fluxes in diffusion models: Source and transport signatures on fluxes and ratios

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    The propagated fluxes of proton, helium, and heavier primary cosmic-ray species (up to Fe) are a means to indirectly access the source spectrum of cosmic rays. We check the compatibility of the primary fluxes with the transport parameters derived from the B/C analysis, but also if they bring further constraints. Proton data are well described in the simplest model defined by a power-law source spectrum and plain diffusion. They can also be accommodated by models with, e.g., convection and/or reacceleration. There is no need for breaks in the source spectral indices below 1\sim 1 TeV/n. Fits on the primary fluxes alone do not provide physical constraints on the transport parameters. If we let free the source spectrum dQ/dE=qβηSRαdQ/dE = q \beta^{\eta_S} {\cal R}^{-\alpha} and fix the diffusion coefficient K(R)=K0βηTRδK(R)= K_0\beta^{\eta_T} {\cal R}^{\delta} such as to reproduce the B/C ratio, the MCMC analysis constrains the source spectral index α\alpha to be in the range 2.22.52.2-2.5 for all primary species up to Fe, regardless of the value of the diffusion slope δ\delta. The ηS\eta_S low-energy shape of the source spectrum is degenerate with the low-energy shape ηT\eta_T of the diffusion coefficient: we find ηSηT0\eta_S-\eta_T\approx 0 for p and He data, but ηSηT1\eta_S-\eta_T\approx 1 for C to Fe primary species. This is consistent with the toy-model calculation in which the shape of the p/He and C/O to Fe/O data is reproduced if ηSηT01\eta_S-\eta_T\approx 0-1 (no need for different slopes α\alpha). When plotted as a function of the kinetic energy per nucleon, the low-energy p/He ratio is shaped mostly by the modulation effect, whereas primary/O ratios are mostly shaped by their destruction rate.Comment: 18 pages, 14 figures: accepted in A&A (1 table added
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