Why do some fields of study in higher education yield higher wage returns in the labor market than others? Human capital perspectives suggest that differences in skills are a major source of ...between-fields wage differentials. We assess this explanation using data from the Programme for the International Assessment of Adult Competencies (PIAAC). Our pooled analysis of 17,590 graduates from 29 countries indicates that differences in general cognitive (literacy and numeracy) skills matter relatively little, although numeracy skills do play a meaningful role in accounting for the high wages of STEM (science, technology, engineering, and mathematics) graduates. Specific skills, proxied by skill use on the job, explain a substantial portion of between-field wage differentials. Remarkably, we find that the sex composition of the field of study remains important after taking skills into account, particularly for explaining the wage advantage of STEM graduates. Comparative analyses grouping the 29 countries into four institutional clusters—Social-democratic, Conservative, Liberal, and Post-communist—show that these general patterns are broadly similar across different institutional contexts.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We show that observations of solar γ rays offer a novel probe of dark matter in scenarios where interactions with the visible sector proceed via a long-lived mediator. As a proof of principle, we ...demonstrate that there exists a class of models which yield solar γ-ray fluxes observable with the next generation of γ-ray telescopes, while being allowed by a variety of current experimental constraints. The parameter space allowed by big bang nucleosynthesis and beam dump experiments naturally leads to mediator lifetimes sufficient to produce observable solar γ-ray signals. The model allows for solar γ-ray fluxes up to orders of magnitude larger compared to dwarf spheroidal galaxies, without reaching equilibrium between dark matter annihilation and capture rate. Our results suggest that solar γ-ray observations are complementary, and in some cases superior, to existing and future dark matter detection efforts.
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A possible hint of dark matter annihilation has been found in Cuoco, Korsmeier and Krämer (2017) from an analysis of recent cosmic-ray antiproton data from AMS-02 and taking into account cosmic-ray ...propagation uncertainties by fitting at the same time dark matter and propagation parameters. Here, we extend this analysis to a wider class of annihilation channels. We find consistent hints of a dark matter signal with an annihilation cross-section close to the thermal value and with masses in range between 40 and 130 GeV depending on the annihilation channel. Furthermore, we investigate in how far the possible signal is compatible with the Galactic center gamma-ray excess and recent observation of dwarf satellite galaxies by performing a joint global fit including uncertainties in the dark matter density profile. As an example, we interpret our results in the framework of the Higgs portal model.
We investigate the impact of external differentiation and vocational orientation of (lower and upper) secondary education on country variation in the mean numeracy skills of, and skills gaps between, ...adults with low and intermediate formal qualifications. We use data on 30- to 44-year-olds in 18 countries from the 2011–12 round of the Program for the International Assessment of Adult Competencies. We find that higher levels of external differentiation (tracking) amplify skills gaps between less- and intermediate-educated adults. This is mainly due to lower mean skills achievement of less-educated adults. By contrast, greater emphasis on vocational skills in upper-secondary education is positively related to numeracy skills for both less- and intermediate-educated adults. Gains are larger for the less educated, so the gap in numeracy skills tends to fall with the degree of vocational orientation. We discuss implications of our findings for research on educational and labor market inequalities.
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BFBNIB, INZLJ, NMLJ, NUK, OILJ, PNG, SAZU, UKNU, UL, UM, UPUK, ZRSKP
Conversion-driven freeze-out is an appealing mechanism to explain the observed relic density while naturally accommodating the null results from direct and indirect detection due to a very weak dark ...matter coupling. Interestingly, the scenario predicts long-lived particles decaying into dark matter with lifetimes favorably coinciding with the range that can be resolved at the LHC. However, the small mass splitting between the long-lived particle and dark matter renders the visible decay products soft, thus challenging current search strategies. We consider four different classes of searches covering the entire range of lifetimes: heavy stable charge particles, disappearing tracks, displaced vertices, and missing energy searches. We discuss the applicability of these searches to conversion-driven freeze-out and derive current constraints highlighting their complementarity. For the displaced vertex search, we demonstrate how a slight modification of the current analysis significantly improves its sensitivity to the scenario. Published by the American Physical Society 2024
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38.
Lyman-α constraints on freeze-in and superWIMPs Decant, Quentin; Heisig, Jan; Hooper, Deanna C. ...
Journal of cosmology and astroparticle physics,
03/2022, Volume:
2022, Issue:
3
Journal Article
Peer reviewed
Open access
Abstract
Dark matter (DM) from freeze-in or superWIMP production is well known to imprint non-cold DM signatures on cosmological observables. We derive constraints from Lyman-
α
forest observations ...for both cases, basing ourselves on a reinterpretation of the existing Lyman-
α
limits on thermal warm DM. We exclude DM masses below 15 keV for freeze-in, in good agreement with previous literature, and provide a generic lower mass bound for superWIMPs that depends on the mother particle decay width. Special emphasis is placed on the mixed scenario, where contributions from both freeze-in and superWIMP are similarly important. In this case, the imprint on cosmological observables can deviate significantly from thermal warm DM. Furthermore, we provide a modified version of the Boltzmann code
class
, analytic expressions for the DM distributions, and fits to the DM transfer functions that account for both mechanisms of production. Moreover, we also derive generic constraints from Δ
N
eff
measurements and show that they cannot compete with those arising from Lyman-
α
observations. For illustration, we apply the above generic limits to a coloured
t
-channel mediator DM model, in which case contributions from both freeze-in through scatterings and decays, as well as superWIMP production can be important. We map out the entire cosmologically viable parameter space, cornered by bounds from Lyman-
α
observations, the LHC, and Big Bang Nucleosynthesis.
Research shows that children of immigrants, the “second generation,” have comparatively high educational aspirations. This “immigrant optimism” translates into ambitious educational choices, given ...the second generation’s level of academic performance. Choice-driven (comprehensive) education systems, which allow the children of immigrants to follow their ambitions, are therefore regarded as facilitating their structural integration. The authors focus on an underappreciated consequence of these findings. If the second generation strives for higher qualifications than children of native-born parents with similar performance, working-age children of immigrants should have lower skills than children of native-born parents with comparable formal education. This could result in (statistical) employer discrimination and ultimately hamper integration. This pattern should be particularly pronounced in choice-driven education systems and in systems that emphasize vocational education. Two-step regression models using data on 16 countries support these expectations. The authors explore implications of these findings for comparative research on ethnic gaps in labor market attainment.
Abstract Less-educated workers have the lowest participation rates in job-related further training across the industrialized world, but the extent of their disadvantage varies. Using data on 28 high- ...and middle-income countries, we assess different explanations for less-educated workers’ training disadvantage relative to intermediate-educated workers, with a focus on the role of labor market allocation (i.e. job tasks, other job features and firm characteristics). Shapley decompositions reveal a broadly similar pattern for all countries: differences in labor market allocation between less- and intermediate-educated workers are more important for explaining the training gap than differences in individual learning disposition (i.e. cognitive skills and motivation to learn). Our analysis further suggests that the training gap is related to educational and labor market institutions and that labor market allocation processes play a key role in mediating any institutional ‘effects’. Strong conclusions regarding the role of institutions are hampered by the small country-level sample, however.
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