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    How likely is it that omitted variable bias will overturn your results?

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    Building on a recently developed methodology for sensitivity analysis that parametrizes omitted variable bias in terms of partial R-Squared measures, I propose a simple statistic to capture the severity of omitted variable bias in any observational study: the probability of omitted variable bias overturning the reported result. The central element of my proposal is formal covariate benchmarking, whereby researchers choose an observed regressor (or a group of observed regressors) to benchmark the relative strength of association of the omitted regressor with the outcome variable and with the treatment variable. These relative strengths of association function as the two sensitivity parameters of the analysis. By allowing these sensitivity parameters to take all permissible values, we get the most conservative estimate of the probability that omitted variable bias can overturn the reported results. By using absolute and relative limits on the maximum values of the sensitivity parameters based on institutional knowledge or other details of the particular study, a researcher can generate less conservative estimates of that probability. For empirical studies with relatively large number of regressors and sample sizes, I suggest bounds for the sensitivity parameters based on simulation studies. I illustrate the methodology using an empirical example that studies the effect of exposure to violence on attitudes towards peace

    Self-assembling polypeptides in complex coacervation

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    Data for Density constrains environmental impacts of fluid abstraction in continental lithium brines

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    This dataset contains all data used in the study Density constrains environmental impacts of fluid abstraction in continental lithium brines. Data include all SEAWAT groundwater-flow model input and output files, which contain all data associated with the parametric modeling study. It also contains NDVI and total annual precipitation datasets used in the study\u27s remote sensing analysis.https://scholarworks.umass.edu/data/1193/thumbnail.jp

    Reproductive Biology of Anadromous Rainbow Smelt, \u3cem\u3eOsmerus mordax\u3c/em\u3e, in the Ipswich Bay Area, Massachusetts

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    The reproductive biology of anadromous rainbow smelt, Osmerus mordax, was investigated in the Parker River and Essex Bay systems from 1977 through 1979. Variations in growth and seasonal energy content of body tissue of young-of-the-year (YOY) anadromous smelt were examined to investigate their relationships to spawning of precocious (age I) fish. By late fall of their first year, YOY that will spawn precociously in the spring have developing gonads, are longer in total length and have a higher energy content (kcals/g) of body tissue than non-precocious fish. The number of fish spawning at age I increased during the spawning season, with male precocious spawners consistently outnumbering female precocious fish. Several aspects of the reproductive ecology of rainbow smelt were examined during the 1979 spawning season. Results from two field experiments indicated that egg survival was positively correlated with water velocity (up to 60 - 80 cm/s). Smelt spawned many more eggs (by a factor of 12 - 15) on aquatic vegetation (Podostemum ceratophyllum abrotanoides) than on two smooth-surfaced substrates (ceramic tile and gravel/ rubble). Survival to hatching on the vegetation was approximately 10% compared to a 1% rate on the other surfaces. In addition, diameter of water-hardened, unfertilized eggs was positively correlated with female total length and prolarval size at hatching. These reproductive characteristics are discussed relative to the life history strategy of anadromous rainbow smelt in the Parker River-Plum Island Sound syste

    Reproduction, First Year Growth and Distribution of Anadromous Rainbow Smelt, \u3cem\u3eOsmerus mordax\u3c/em\u3e (Mitchill), in the Paker River-Plum Island Sound Estuary, Massachusetts

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    The reproductive biology of anadromous rainbow smelt, Osmerus mordax (Mitchill), in the Parker River-Plum Island Sound estuary was investigated during the fall 1974 and spring 1975. Only one set of maturing eggs was observed within the ovaries of fish examined; all ovarian locations matured at a similar rate. Larger fish produced larger ovaries and eggs but fewer eggs per gram of ovarian weight. Mean maturity indices for females and males during November through March increased 576.7% and 72.1%, respectively. Total fecundity ranged from 7,038 eggs for an age I, 127 mm female to 44,241 eggs for an age II, 204 mm specimen. Fecundity correlated highest with ovarian weight. In 1975 spawning commenced in the Parker River on 17 March and terminated in Cart Creek on 27 April; corresponding water temperatures were 4.0°C and 8.3°C, respectively. The mean egg densities for spawning sites in Cart Creek and the Mill River were 0.79 and 0.23 eggs/cm2 , respectively. A total egg population in Cart Creek of 1,772,492 ± 278,881 was estimated by a representative but disproportionate sampling technique. Spawning stock abundance was calculated from the egg population estimate. The influence of environmental factors upon spawning activity was examined with stepwise multiple regression; only one variable, tidal periodicity, was highly significant. Peaks of spawning activity corresponded with the bimonthly spring tides

    The Woman Destroyed (and now edible)

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    Literary Inspiration: The Woman Destroyed by Simone de Beauvoirhttps://scholarworks.umass.edu/ediblebookfest_2022/1022/thumbnail.jp

    Using Evidence-Based Interventions to Improve the Completion Rates of Advance Care Directives

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    Background: Advance care directives reduce unnecessary suffering, improve life quality, and further engage patients and families in the decision-making process to ensure that end-of-life care preferences are considered and applied. Despite the proven benefits of advance care directives, advance directives completion rates are approximately 33% in the United States. Purpose: The purpose of this quality improvement project was to increase advance directive completion rates among patients at one clinic through an educational intervention. Methods: The intervention was used to educate patients about the benefits of advance care directives, and present opportunities for patients to complete the directive. The intervention included educational pamphlets and posters available in the clinic waiting room. The participants included patients and their families who attend the clinic. Results and Conclusion: The educational campaign resulted in a 20.3% increase in the completion rates of advance directives among the randomly selected health records. Age, gender, and race were found to be influential factors in patients’ attitudes toward completing advance directives. This quality improvement project supports the application of an educational intervention to increase the completion rates of advance directives in clinics caring for patients who are immigrants, refugees, and low-income earners

    Source data for Flowering of Developable 2D Crystal Shapes in Closed, Fluid Membranes

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    Source data for Flowering of Developable 2D Crystal Shapes in Closed, Fluid Membranes .https://scholarworks.umass.edu/data/1189/thumbnail.jp

    Luzhin\u27s Cake

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    Literary Inspiration: The Luzhin Defense by Vladmir Nabokovhttps://scholarworks.umass.edu/ediblebookfest_2022/1021/thumbnail.jp

    Data for Rates of bedrock canyon incision by megafloods, Channeled Scabland, USA

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    This is the data repository associated with the manuscript \u27Rates of bedrock canyon incision by megafloods, Channeled Scabland, USA,\u27 containing all code, input files, and output files relevant to the project. Details about the content of the data repository can be found in the readme.txt file located in the repository.https://scholarworks.umass.edu/data/1191/thumbnail.jp

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