8,403 research outputs found

    The American High School Graduation Rate: Trends and Levels

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    This paper uses multiple data sources and a unified methodology to estimate the trends and levels of the U.S. high school graduation rate. Correcting for important biases that plague previous calculations, we establish that (a) the true high school graduation rate is substantially lower than the official rate issued by the National Center for Educational Statistics; (b) it has been declining over the past 40 years; (c) majority/minority graduation rate differentials are substantial and have not converged over the past 35 years; (d) the decline in high school graduation rates occurs among native populations and is not solely a consequence of increasing proportions of immigrants and minorities in American society; (e) the decline in high school graduation explains part of the recent slowdown in college attendance; and (f) the pattern of the decline of high school graduation rates by gender helps to explain the recent increase in male-female college attendance gaps.

    Grand Unified Yukawa Matrix Ansatz: The Standard Model Fermion Mass, Quark Mixing and CP Violation Parameters

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    We propose a new mass matrix ansatz: At the grand unified (GU) scale, the standard model (SM) Yukawa coupling matrix elements are integer powers of the square root of the GU gauge coupling constant \varepsilon \equiv \sqrt{\alpha_{\text{GU}}}, multiplied by order unity random complex numbers. It relates the hierarchy of the SM ermion masses and quark mixings to the gauge coupling constants, greatly reducing the SM parameters, and can give good fitting results of the SM fermion mass, quark mixing and CP violation parameters. This is a neat but very effective ansatz.Comment: 4 pages (two columns), by REVTeX 4, 2 tables, no figures, version for publication in CP

    The determinants of participation in a social program: Evidence from a prototypical job training program

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    This paper decomposes the participation process of a prototypical program into eligibility, awareness, application, acceptance and enrollment. With this decomposition, we determine the sources of unequal participation for different groups, and demonstrate that variables often have very different effects at different stages in the participation process. Our analysis shows that personal choices substantially affect participation and that awareness of program eligibility is a major source of variation in participation.Social program participation; job training performance standards; cream skimming; job training partnership act (JTPA)

    The Determinants of Participation in a Social Program: Evidence from a Prototypical Job Training Program

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    This paper decomposes the participation process of a prototypical program into eligibility, awareness, application, acceptance and enrollment. With this decomposition, we determine the sources of unequal participation for different groups, and demonstrate that variables often have very different effects at different stages in the participation process. Our analysis shows that personal choices substantially affect participation and that awareness of program eligibility is a major source of variation in participation.

    Local Starbursts in a Cosmological Context

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    In this contribution I introduce some of the major issues that motivate the conference, with an emphasis on how starbursts fit into the ``big picture''. I begin by defining starbursts in several different ways, and discuss the merits and limitations of these definitions. I will argue that the most physically useful definition of a starburst is its ``intensity'' (star formation rate per unit area). This is the most natural parameter to compare local starbursts with physically similar galaxies at high redshift, and indeed I will argue that local starbursts are unique laboratories to study the processes at work in the early universe. I will describe how NASA's GALEX mission has uncovered a rare population of close analogs to Lyman Break Galaxies in the local universe. I will then compare local starbursts to the Lyman-Break and sub-mm galaxies high redshift populations, and speculate that the multidimensional ``manifold'' of starbursts near and far can be understood largely in terms of the Schmidt/Kennicutt law and galaxy mass-metallicity relation. I will briefly summarize he properties of starburst-driven galactic superwinds and their possible implications for the evolution of galaxies and the IGM. These complex multiphase flows are best studied in nearby starbursts, where we can study the the hot X-ray gas that contains the bulk of the energy and newly produced metals.Comment: Proceedings of the Conference "Starbursts: Fropm 30 Doradus to Lyman Break Galaxies

    Taking the Easy Way Out: How the GED Testing Program Induces Students to Drop Out

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    We exploit an exogenous increase in General Educational Development (GED) testing requirements to determine whether raising the difficulty of the test causes students to finish high school rather than drop out and GED certify. We find that a six point decrease in GED pass rates induces a 1.3 point decline in overall dropout rates. The effect size is also much larger for older students and minorities. Finally, a natural experiment based on the late introduction of the GED in California reveals, that adopting the program increased the dropout rate by 3 points more relative to other states during the mid-1970s.GED, dropout

    Separate ways: The Mass-Metallicity Relation does not strongly correlate with Star Formation Rate in SDSS-IV MaNGA galaxies

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    We present the integrated stellar mass-metallicity relation (MZR) for more than 1700 galaxies included in the integral field area SDSS-IV MaNGA survey. The spatially resolved data allow us to determine the metallicity at the same physical scale (effective radius in arcsecs, Reff\mathrm{R_{eff}} ) using a heterogeneous set of ten abundance calibrators. Besides scale factors, the shape of the MZR is similar for all calibrators, consistent with those reported previously using single-fiber and integral field spectroscopy. We compare the residuals of this relation against the star formation rate (SFR) and specific SFR (sSFR). We do not find a strong secondary relation of the MZR with either SFR or the sSFR for any of the calibrators, in contrast with previous single-fiber spectroscopic studies. Our results agree with an scenario in which metal enrichment happens at local scales, with global outflows playing a secondary role in shaping the chemistry of galaxies and cold-gas inflows regulating the stellar formation.Comment: 10 pages, 9 Figures. Accepted for publication in Ap
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