2,550 research outputs found

    Health Reform, Health Insurance, and Selection: Estimating Selection into Health Insurance Using the Massachusetts Health Reform

    Get PDF
    We implement an empirical test for selection into health insurance using changes in coverage induced by the introduction of mandated health insurance in Massachusetts. Our test examines changes in the cost of the newly insured relative to those who were insured prior to the reform. We find that counties with larger increases in insurance coverage over the reform period face the smallest increase in average hospital costs for the insured population, consistent with adverse selection into insurance before the reform. Additional results, incorporating cross-state variation and data on health measures, provide further evidence for adverse selection.

    Health Reform, Health Insurance, and Selection: Estimating Selection into Health Insurance Using the Massachusetts Health Reform

    Get PDF
    We implement an empirical test for selection into health insurance using changes in coverage induced by the introduction of mandated health insurance in Massachusetts. Our test examines changes in the cost of the newly insured relative to those who were insured prior to the reform. We find that counties with larger increases in insurance coverage over the reform period face the smallest increase in average hospital costs for the insured population, consistent with adverse selection into insurance before the reform. Additional results, incorporating cross-state variation and data on health measures, provide further evidence for adverse selection.Adverse selection, Massachusetts, Health reform

    Thematic Collection: The Canadian Field-Naturalist, Documenting Species New to Canada for Nearly a Century

    Get PDF
    Thematic Collection: The Canadian Field-Naturalist, Documenting Species New to Canada for Nearly a Centur

    Adverse Selection and an Individual Mandate: When Theory Meets Practice

    Get PDF
    We develop a model of selection that incorporates a key element of recent health reforms: an individual mandate. We identify a set of key parameters for welfare analysis, allowing us to model the welfare impact of the actual policy as well as to estimate the socially optimal penalty level. Using data from Massachusetts, we estimate the key parameters of the model. We compare health insurance coverage, premiums, and insurer average health claim expenditures between Massachusetts and other states in the periods before and after the passage of Massachusetts health reform. In the individual market for health insurance, we ļ¬nd that premiums and average costs decreased signiļ¬cantly in response to the individual mandate; consistent with an initially adversely selected insurance market. We are also able to recover an estimated willingness-to-pay for health insurance. Combining demand and cost estimates as suļ¬€icient statistics for welfare analysis, we ļ¬nd an annual welfare gain of 335dollarsperpersonor335 dollars per person or 71 million annually in Massachusetts as a result of the reduction in adverse selection. We also ļ¬nd evidence for smaller post-reform markups in the individual market, which increased welfare by another 107dollarsperpersonperyearandabout107 dollars per person per year and about 23 million per year overall. To put this in perspective, the total welfare gains were 8.4% of medical expenditures paid by insurers. Our model and empirical estimates suggest an optimal mandate penalty of $2,190. A penalty of this magnitude would increase health insurance to near universal levels. Our estimated optimal penalty is higher than the individual mandate penalty adopted in Massachusetts but close to the penalty implemented under the ACA

    Health Reform, Health Insurance, and Selection: Estimating Selection Into Health Insurance Using the Massachusetts Health Reform

    Get PDF
    We implement an empirical test for selection into health insurance using changes in coverage induced by the introduction of mandated health insurance in Massachusetts. Our test examines changes in the cost of the newly insured relative to those who were insured prior to the reform. We find that counties with larger increases in insurance coverage over the reform period face the smallest increase in average hospital costs for the insured population, consistent with adverse selection into insurance before the reform. Additional results, incorporating cross-state variation and data on health measures, provide further evidence for adverse selection

    Preā€“post intervention exploring cognitive function and relationships with weight loss, intervention adherence and dropout

    Get PDF
    Objective: To evaluate the association between baseline cognitive function, intervention dropout, adherence and 3-month weight loss (WL) when controlling for confounding demographic variables. Methods: 107 (Mage = 40.9 yrs.), BMI in the overweight and obese range (BMI = 35.6 kg/m2), men (N = 17) and women (N = 90) completed a 3-month WL intervention. Participants attended weekly behavioral sessions, comply with a reduced calorie diet, and complete 100 min of physical activity (PA)/wk. Cognitive function tasks at baseline included Flanker (attention), Stroop (executive control) and working memory, demographics, body weight and cardiovascular fitness were assessed at baseline. Session attendance, adherence to PA and diet were recorded weekly. Results: Baseline attention was positively correlated with age (p \u3c .05), education (p \u3c .05), attendance (p \u3c .05), diet (p \u3c .05) and PA (p \u3c .05). Baseline executive control (p \u3c .05) and working memory (p \u3c .05) were each associated with % WL. Baseline executive control (p \u3c .01) and working memory (p \u3c .001) were also each associated with education. ANOVA indicated that baseline attention (p \u3c .01) was associated with WL, specifically for comparing those who achieved 5ā€“10% WL (p \u3c .01) and those who achieved greater than 10% WL (p \u3c .01) to those who dropped. Significance: Results suggest that stronger baseline attention is associated with completion of a 3-mo. WL intervention. Executive control and working memory are associated with amount of WL achieved. NCT registration: US NIH Clinical Trials, NCT0166471

    Effect of Heat Shock, Pretreatment and Hsp70 Copy Number on Wing Development in Drosophila Melanogaster

    Get PDF
    Naturally Occurring Heat Shock (HS) during Pupation Induces Abnormal Wing Development in Drosophila; We Examined Factors Affecting the Severity of This Induction. the Proportion of HS-Surviving Adults with Abnormal Wings Varied with HS Duration and Intensity, and with the Pupal Age or Stage at HS Administration. Pretreatment (PT), Mild Hyperthermia Delivered Before HS, Usually Protected Development Against HS. Gradual Heating Resembling Natural Thermal Regimes Also Protected Wing Development Against Thermal Disruption. Because of the Roles of the Wings in Flight and Courtship and in View of Natural Thermal Regimes that Drosophila Experience, Both HS-Induction of Wing Abnormalities and its Abatement by PT May Have Marked Effects on Drosophila Fitness in Nature. Because PT is Associated with Expression of Heat-Inducible Molecular Chaperones Such as Hsp70 in Drosophila, We Compared Thermal Disruption of Wing Development among Hsp70 Mutants as Well as among Strains Naturally Varying in Hsp70 Levels. Contrary to Expectations, Lines or Strains with Increased Hsp70 Levels Were No More Resistant to HS-Disruption of Wing Development Than Counterparts with Lower Hsp70 Levels. in Fact, Wing Development Was More Resistant to HS in Hsp70 Deletion Strains Than Control Strains. We Suggest that, While High Hsp70 Levels May Aid Cells in Surviving Hyperthermia, High Levels May Also Overly Stimulate or Inhibit Numerous Signaling Pathways Involved in Cell Proliferation, Maturation and Programmed Death, Resulting in Developmental Failure

    Matrix quality and disturbance frequency drive evolution of species behavior at habitat boundaries

    Get PDF
    Previous theoretical studies suggest that a species' landscape should influence the evolution of its dispersal characteristics, because landscape structure affects the costs and benefits of dispersal. However, these studies have not considered the evolution of boundary crossing, that is, the tendency of animals to cross from habitat to nonhabitat ("matrix"). It is important to understand this dispersal behavior, because of its effects on the probability of population persistence. Boundary-crossing behavior drives the rate of interaction with matrix, and thus, it influences the rate of movement among populations and the risk of dispersal mortality. We used an individual-based, spatially explicit model to simulate the evolution of boundary crossing in response to landscape structure. Our simulations predict higher evolved probabilities of boundary crossing in landscapes with more habitat, less fragmented habitat, higher-quality matrix, and more frequent disturbances (i.e., fewer generations between local population extinction events). Unexpectedly, our simulations also suggest that matrix quality and disturbance frequency have much stronger effects on the evolution of boundary crossing than either habitat amount or habitat fragmentation. Our results suggest that boundary-crossing responses are most affected by the costs of dispersal through matrix and the benefits of escaping local extinction events. Evolution of optimal behavior at habitat boundaries in response to the landscape may have implications for species in human-altered landscapes, because this behavior may become suboptimal if the landscape changes faster than the species' evolutionary response to that change. Understanding how matrix quality and habitat disturbance drive evolution of behavior at boundaries, and how this in turn influences the extinction risk of species in human-altered landscapes should help us identify species of conservation concern and target them for management

    Halo Star Streams in the Solar Neighborhood

    Full text link
    We have assembled a sample of halo stars in the solar neighborhood to look for halo substructure in velocity and angular momentum space. Our sample includes red giants, RR Lyrae, and red horizontal branch stars within 2.5 kpc of the Sun with [Fe/H] less than -1.0. It was chosen to include stars with accurate distances, space velocities, and metallicities as well as well-quantified errors. We confirm the existence of the streams found by Helmi and coworkers, which we refer to as the H99 streams. These streams have a double-peaked velocity distribution in the z direction. We use the results of modeling of the H99 streams by Helmi and collaborators to test how one might use v_z velocity information and radial velocity information to detect kinematic substructure in the halo. We find that detecting the H99 streams with radial velocities alone would require a large sample. We use the velocity distribution of the H99 streams to estimate their age. From our model of the progenitor of the H99 streams, we determine that it was accreted between 6 and 9 Gyr ago. The H99 streams have [alpha/Fe] abundances similar to other halo stars in the solar neighborhood, suggesting that the gas that formed these stars were enriched mostly by Type II SNe. We have also discovered in angular momentum space two other possible substructures, which we refer to as the retrograde and prograde outliers. The retrograde outliers are likely to be halo substructure, but the prograde outliers are most likely part of the smooth halo. The retrograde outliers have significant structure in the v_phi direction and show a range of [alpha/Fe]. The methods presented in this paper can be used to exploit the kinematic information present in future large databases like RAVE, SDSSII/SEGUE, and Gaia.Comment: 46 pages, 13 figures, and 9 tables. Minor changes to text to match proofed version of the paper. Low resolution figures. High resolution version at http://www.astro.wisc.edu/~kepley/solar_streams.p
    • ā€¦
    corecore