166 research outputs found

    Hestenes' Tetrad and Spin Connections

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    Defining a spin connection is necessary for formulating Dirac's bispinor equation in a curved space-time. Hestenes has shown that a bispinor field is equivalent to an orthonormal tetrad of vector fields together with a complex scalar field. In this paper, we show that using Hestenes' tetrad for the spin connection in a Riemannian space-time leads to a Yang-Mills formulation of the Dirac Lagrangian in which the bispinor field is mapped to a set of Yang-Mills gauge potentials and a complex scalar field. This result was previously proved for a Minkowski space-time using Fierz identities. As an application we derive several different non-Riemannian spin connections found in the literature directly from an arbitrary linear connection acting on Hestenes' tetrad and scalar fields. We also derive spin connections for which Dirac's bispinor equation is form invariant. Previous work has not considered form invariance of the Dirac equation as a criterion for defining a general spin connection

    Does correcting myths about the flu vaccine work? An experimental evaluation of the effects of corrective information

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    Seasonal influenza is responsible for thousands of deaths and billions of dollars of medical costs per year in the United States, but influenza vaccination coverage remains substantially below public health targets. One possible obstacle to greater immunization rates is the false belief that it is possible to contract the flu from the flu vaccine. A nationally representative survey experiment was conducted to assess the extent of this flu vaccine misperception. We find that a substantial portion of the public (43%) believes that the flu vaccine can give you the flu. We also evaluate how an intervention designed to address this concern affects belief in the myth, concerns about flu vaccine safety, and future intent to vaccinate. Corrective information adapted from the Centers for Disease Control and Prevention (CDC) website significantly reduced belief in the myth that the flu vaccine can give you the flu as well as concerns about its safety. However, the correction also significantly reduced intent to vaccinate among respondents with high levels of concern about vaccine side effects--a response that was not observed among those with low levels of concern. This result, which is consistent with previous research on misperceptions about the MMR vaccine, suggests that correcting myths about vaccines may not be an effective approach to promoting immunization

    Displacing misinformation about events: An experimental test of causal corrections

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    PublishedMisinformation can be very difficult to correct and may have lasting effects even after it is discredited. One reason for this persistence is the manner in which people make causal inferences based on available information about a given event or outcome. As a result, false information may continue to influence beliefs and attitudes even after being debunked if it is not replaced by an alternate causal explanation. We test this hypothesis using an experimental paradigm adapted from the psychology literature on the continued influence effect and find that a causal explanation for an unexplained event is significantly more effective than a denial even when the denial is backed by unusually strong evidence. This result has significant implications for how to most effectively counter misinformation about controversial political events and outcomes.We are grateful to Democracy Fund and the New America Foundation for funding support and to Rune Slothuus and Dannagal Young for helpful comments

    The roles of information deficits and identity threat in the prevalence of misperceptions

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    This is the author accepted manuscript. The final version is available from Taylor & Francis (Routledge) via the DOI in this record.Why do so many Americans hold misperceptions? We examine two factors that contribute to the prevalence of these beliefs. First, presenting correct information should reduce misperceptions, especially if provided in a clear and compelling format. We therefore test the effect of graphical information, which may be especially effective in facilitating belief updating about changes in quantities over time. In some cases, though, people may reject information because it threatens their worldview or self-concept – a mechanism that can be revealed by affirming individuals’ self-worth, which could make them more willing to acknowledge uncomfortable facts. We test both mechanisms jointly. In three experiments, we find that providing information in graphical form reduces misperceptions. A third study shows that this effect is greater than for equivalent textual information. Our findings for self-affirmation are more equivocal. We find limited evidence that self-affirmation can help diminish misperceptions when no other information is provided, but it does not consistently increase willingness to accept corrective information as previous research in social psychology would suggest. These results suggest that misperceptions are caused by a lack of information as well as psychological threat, but that these factors may interact in ways that are not yet well understood.We thank John Aldrich for providing time on the 2008 Congressional Campaign Election Survey. Nyhan thanks the Robert Wood Johnson Foundation Scholars in Health Policy Research Program for generous funding support

    Understanding Innovations in Journalistic Practice: A Field Experiment Examining Motivations for Fact-Checking

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    © 2016 International Communication Association. Why has fact-checking spread so quickly within U.S. political journalism? In the first field experiment conducted among reporters, we varied journalist exposure to messages that highlight either audience demand for fact-checking or the prestige it enjoys within the profession. Our results indicate that messages promoting the high status and journalistic values of fact-checking increased the prevalence of fact-checking coverage, while messages about audience demand were somewhat less successful. These findings suggest that political fact-checking is driven primarily by professional motives within journalism, a finding that helps us understand the process by which the practice spreads within the press as well as the factors that influence the behavior of journalists

    The structure of foreign policy attitudes in transatlantic perspective: comparing the United States, United Kingdom, France and Germany

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    While public opinion about foreign policy has been studied extensively in the United States, there is less systematic research of foreign policy opinions in other countries. Given that public opinion about international affairs affects who gets elected in democracies and then constrains the foreign policies available to leaders once elected, both comparative politics and international relations scholarship benefit from more systematic investigation of foreign policy attitudes outside the United States. Using new data, this article presents a common set of core constructs structuring both American and European attitudes about foreign policy. Surveys conducted in four countries (the United States, the United Kingdom, France and Germany) provide an expanded set of foreign policy‐related survey items that are analysed using exploratory structural equation modeling (ESEM). Measurement equivalence is specifically tested and a common four‐factor structure that fits the data in all four countries is found. Consequently, valid, direct comparisons of the foreign policy preferences of four world powers are made. In the process, the four‐factor model confirms and expands previous work on the structure of foreign policy attitudes. The article also demonstrates the capability of ESEM in testing the dimensionality and cross‐national equivalence of social science concepts

    Taking Fact-Checks Literally But Not Seriously? The Effects of Journalistic Fact-Checking on Factual Beliefs and Candidate Favorability

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    This is the author accepted manuscript. The final version is available from Springer via the DOI in this record.Are citizens willing to accept journalistic fact-checks of misleading claims from candidates they support and to update their attitudes about those candidates? Previous studies have reached conflicting conclusions about the effects of exposure to counter-attitudinal information. As fact-checking has become more prominent, it is therefore worth examining how respondents respond to fact-checks of politicians—a question with important implications for understanding the effects of this journalistic format on elections. We present results to two experiments conducted during the 2016 campaign that test the effects of exposure to realistic journalistic fact-checks of claims made by Donald Trump during his convention speech and a general election debate. These messages improved the accuracy of respondents’ factual beliefs, even among his supporters, but had no measurable effect on attitudes toward Trump. These results suggest that journalistic fact-checks can reduce misperceptions but often have minimal effects on candidate evaluations or vote choice

    Competing risks of cancer mortality and cardiovascular events in individuals with multimorbidity

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    Background: Cancer patients with cardiovascular and other comorbidities are at concurrent risk of multiple adverse outcomes. However, most treatment decisions are guided by evidence from single-outcome models, which may be misleading for multimorbid patients. Objective: We assessed the interacting effects of cancer, cardiovascular, and other morbidity burdens on the competing outcomes of cancer mortality, serious cardiovascular events, and other-cause mortality. Design: We analyzed a cohort of 6,500 adults with initial cancer diagnosis between 2001 and 2008, SEER 5-year survival ≥26%, and a range of cardiovascular risk factors. We estimated the cumulative incidence of cancer mortality, a serious cardiovascular event (myocardial infarction, coronary revascularization, or cardiovascular mortality), and other-cause mortality over 5 years, and identified factors associated with the competing risks of each outcome using cause-specific Cox proportional hazard models. Results: Following cancer diagnosis, there were 996 (15.3%) cancer deaths, 328 (5.1%) serious cardiovascular events, and 542 (8.3%) deaths from other causes. In all, 4,634 (71.3%) cohort members had none of these outcomes. Although cancer prognosis had the greatest effect, cardiovascular and other morbidity also independently increased the hazard of each outcome. The effect of cancer prognosis on outcome was greatest in year 1, and the effect of other morbidity was greater in individuals with better cancer prognoses. Conclusion: In multimorbid oncology populations, comorbidities interact to affect the competing risk of different outcomes. Quantifying these risks may provide persons with cancer plus cardiovascular and other comorbidities more accurate information for shared decision-making than risks calculated from single-outcome models. Journal of Comorbidity 2014:4(1):29–3

    Not Just Asking Questions: Effects of Implicit and Explicit Conspiracy Information About Vaccines and Genetic Modification

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    This is the author accepted manuscript. The final version is available from Taylor & Francis (Routledge) via the DOI in this record.While conspiracy ideation has attracted overdue attention from social scientists in recent years, little work focuses on how different pro-conspiracy messages affect the take-up of conspiracy beliefs. In this study, we compare the effect of explicit and implicit conspiracy cues on the adoption of conspiracy beliefs. We also examine whether corrective information can undo conspiracy cues, and whether there are differences in the effectiveness of corrective information based on whether a respondent received an explicit or implicit conspiracy cue. We examine these questions using a real-world but low-salience conspiracy theory concerning Zika, GM mosquitoes, and vaccines. Using a preregistered experiment (N = 1018: https://osf.io/hj2pw/), we find that both explicit and implicit conspiracy cues increase conspiracy beliefs, but in both cases corrections are generally effective. We also find reception of an explicit conspiracy cue and its correction is conditional on feelings toward the media and pharmaceutical companies. Finally, we find that examining open-ended conspiracy belief items reveals similar patterns, but with a few key differences. These findings have implications for how news media cover controversial public health issues going forward.European Research Counci

    Exposure to untrustworthy websites in the 2016 US election

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    This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability: Data files necessary to replicate the results in this article are available at the following Dataverse repository: https://doi.org/10.7910/DVN/YLW1AZCode availability: R/Stata scripts that replicate the results in this article are available at the following Dataverse repository: https://doi.org/10.7910/DVN/YLW1AZAlthough commentators frequently warn about echo chambers, little is known about the volume or slant of political misinformation that people consume online, the effects of social media and fact checking on exposure, or the effects of political misinformation on behaviour. Here, we evaluate these questions for websites that publish factually dubious content, which is often described as fake news. Survey and web-traffic data from the 2016 US presidential campaign show that supporters of Donald Trump were most likely to visit these websites, which often spread through Facebook. However, these websites made up a small share of people’s information diets on average and were largely consumed by a subset of Americans with strong preferences for pro-attitudinal information. These results suggest that the widespread speculation about the prevalence of exposure to untrustworthy websites has been overstated.European Union Horizon 2020Poynter InstituteKnight FoundationAmerican Press Institut
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