The effects of Facebook and Instagram on the 2020 election: A deactivation experiment.

We study the effect of Facebook and Instagram access on political beliefs, attitudes, and behavior by randomizing a subset of 19,857 Facebook users and 15,585 Instagram users to deactivate their accounts for 6 wk before the 2020 U.S. election. We report four key findings. First, both Facebook and Instagram deactivation reduced an index of political participation (driven mainly by reduced participation online). Second, Facebook deactivation had no significant effect on an index of knowledge, but secondary analyses suggest that it reduced knowledge of general news while possibly also decreasing belief in misinformation circulating online. Third, Facebook deactivation may have reduced self-reported net votes for Trump, though this effect does not meet our preregistered significance threshold. Finally, the effects of both Facebook and Instagram deactivation on affective and issue polarization, perceived legitimacy of the election, candidate favorability, and voter turnout were all precisely estimated and close to zero.

Change in Epidemiology of Creutzfeldt-Jakob Disease in the US, 2007-2020.

This cross-sectional study uses Centers for Disease Control and Prevention multiple cause of death data to examine recent US trends in Creutzfeldt-Jakob disease.

Private Equity Acquisitions Of Ambulatory Surgical Centers Were Not Associated With Quality, Cost, Or Volume Changes.

Ambulatory surgical centers (ASCs) are increasingly being acquired by private equity firms, yet the implications for patients remain understudied. In this study we employed a quasi-experimental difference-in-differences design within an event study framework to assess changes in outcomes associated with the acquisition of ASCs by private equity entities. Using a two-way fixed effects model, we assessed the baseline probability of an unplanned hospital visit, total costs, and total encounters three years preacquisition compared with three years postacquisition in ASCs acquired by private equity versus those acquired by non-private equity entities. We identified ninety-one ASCs acquired by private equity and fifty-seven ASCs acquired by non-private equity entities during the period 2011-14. There was no statistically significant observed change in the probability of an unplanned hospital visit, total costs, or total encounters after acquisition by private equity relative to acquisition by non-private equity entities. When we compared private equity-acquired ASCs with matched ASCs that were never acquired, we also found no statistically significant relative change in the probability of an unplanned hospital visit, total costs, or total encounters. Regulators should ensure that data on private equity acquisitions are transparent and that data are available to track the long-term quality and financial implications of these acquisitions.

Gaps between official and excess Covid-19 mortality measures: The effects of institutional quality and vaccinations.

We evaluate quartile rankings of countries during the Covid-19 pandemic using both official (confirmed) and excess mortality data. By December 2021, the quartile rankings of three-fifths of the countries differ when ranked by excess vs. official mortality. Countries that are 'doing substantially better' in the excess mortality are characterized by higher urban population shares; higher GDP/Capita; and higher scores on institutional and policy variables. We perform two regressions in which the ratio of Cumulative Excess to Official Covid-19 mortalities (E/O ratio) is regressed on covariates. In a narrow study, controlling for GDP/Capita and vaccination rates, by December 2021 the E/O ratio was smaller in countries with higher vaccination rates. In a broad study, adding institutional and policy variables, the E/O ratio was smaller in countries with higher degree of voice and accountability. The arrival of vaccines in 2021 and voice and accountability had a discernible association on the E/O ratio.

Accounting for Global COVID-19 Diffusion Patterns, January-April 2020.

Key factors in modeling a pandemic and guiding policy-making include mortality rates associated with infections; the ability of government policies, medical systems, and society to adapt to the changing dynamics of a pandemic; and institutional and demographic characteristics affecting citizens' perceptions and behavioral responses to stringent policies. This paper traces the cross-country associations between COVID-19 mortality, policy interventions aimed at limiting social contact, and their interactions with institutional and demographic characteristics. We document that, with a lag, more stringent pandemic policies were associated with lower mortality growth rates. The association between stricter pandemic policies and lower future mortality growth is more pronounced in countries with a greater proportion of the elderly population and urban population, greater democratic freedoms, and larger international travel flows. Countries with greater policy stringency in place prior to the first death realized lower peak mortality rates and exhibited lower durations to the first mortality peak. In contrast, countries with higher initial mobility saw higher peak mortality rates in the first phase of the pandemic, and countries with a larger elderly population, a greater share of employees in vulnerable occupations, and a higher level of democracy took longer to reach their peak mortalities. Our results suggest that policy interventions are effective at slowing the geometric pattern of mortality growth, reducing the peak mortality, and shortening the duration to the first peak. We also shed light on the importance of institutional and demographic characteristics in guiding policy-making for future waves of the pandemic.