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Objectives: Pragmatic randomised controlled trials (pRCTs) are essential for determining the real-world safety and effectiveness of healthcare interventions. However, both laypeople and clinicians often demonstrate experiment aversion: preferring to implement either of two interventions for everyone rather than comparing them to determine which is best. We studied whether clinician and layperson views of pRCTs for COVID-19, as well as non-COVID-19, interventions became more positive during the pandemic, which increased both the urgency and public discussion of pRCTs., Design: Randomised survey experiments., Setting: Geisinger, a network of hospitals and clinics in central and northeastern Pennsylvania, USA; Amazon Mechanical Turk, a research participant platform used to recruit online participants residing across the USA. Data were collected between August 2020 and February 2021., Participants: 2149 clinicians (the types of people who conduct or make decisions about conducting pRCTs) and 2909 laypeople (the types of people who are included in pRCTs as patients). The clinician sample was primarily female (81%), comprised doctors (15%), physician assistants (9%), registered nurses (54%) and other medical professionals, including other nurses, genetic counsellors and medical students (23%), and the majority of clinicians (62%) had more than 10 years of experience. The layperson sample ranges in age from 18 to 88 years old (mean=38, SD=13) and the majority were white (75%) and female (56%)., Outcome Measures: Participants read vignettes in which a hypothetical decision-maker who sought to improve health could choose to implement intervention A for all, implement intervention B for all, or experimentally compare A and B and implement the superior intervention. Participants rated and ranked the appropriateness of each decision. Experiment aversion was defined as the degree to which a participant rated the experiment below their lowest-rated intervention., Results: In a survey of laypeople administered during the pandemic, we found significant aversion to experiments involving catheterisation checklists and hypertension drugs unrelated to the treatment of COVID-19 (Cohen's d =0.25-0.46, p <0.001). Similarly, among both laypeople and clinicians, we found significant aversion to most (comparing different checklist, proning and mask protocols; Cohen's d =0.17-0.56, p <0.001) but not all (comparing school reopening protocols; Cohen's d =0.03, p =0.64) non-pharmaceutical COVID-19 experiments. Interestingly, we found the lowest experiment aversion to pharmaceutical COVID-19 experiments (comparing new drugs and new vaccine protocols for treating the novel coronavirus; Cohen's d =0.04-0.12, p =0.12-0.55). Across all vignettes and samples, 28%-57% of participants expressed experiment aversion, whereas only 6%-35% expressed experiment appreciation by rating the trial higher than their highest-rated intervention., Conclusions: Advancing evidence-based medicine through pRCTs will require anticipating and addressing experiment aversion among patients and healthcare professionals., Study Registration: http://osf.io/6p5c7/., Competing Interests: Competing interests: The authors are or were, at the time the research was conducted, affiliated with the same nonprofit health system (Geisinger) from which the clinician sample was recruited., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The Social Shapes Test (SST) is a measure of social intelligence which does not use human faces or rely on extensive verbal ability. The SST has shown promising validity among adults without autism spectrum disorder (ASD), but it is uncertain whether it is suitable for adults with ASD. We find measurement invariance between adults with (n = 229) or without ASD (n = 1,049) on the 23-item SST. We also find that adults without ASD score higher on the SST than adults with ASD (d = 0.21). We also provide two, 14-item versions which demonstrated good parallel test-retest reliability and are positively related to scores on the Frith-Happé task. The SST is suitable for remote, online research studies., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Traditionally, scientists have placed more emphasis on communicating inferential uncertainty (i.e., the precision of statistical estimates) compared to outcome variability (i.e., the predictability of individual outcomes). Here, we show that this can lead to sizable misperceptions about the implications of scientific results. Specifically, we present three preregistered, randomized experiments where participants saw the same scientific findings visualized as showing only inferential uncertainty, only outcome variability, or both and answered questions about the size and importance of findings they were shown. Our results, composed of responses from medical professionals, professional data scientists, and tenure-track faculty, show that the prevalent form of visualizing only inferential uncertainty can lead to significant overestimates of treatment effects, even among highly trained experts. In contrast, we find that depicting both inferential uncertainty and outcome variability leads to more accurate perceptions of results while appearing to leave other subjective impressions of the results unchanged, on average.

The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic 3 He, 21 Ne, and 38 Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic 10 Be concentration point to a small 40-60 cm diameter meteoroid. An 40 Ar- 39 Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA-ICPMS give an average Pb-Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb-Pb phosphate age of 4535.3 ± 9.5 Ma and U-Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system., (© 2020 The Authors. Meteoritics & Planetary Science published by Wiley Periodicals LLC on behalf of The Meteoritical Society (MET).)

We resolve a controversy over two competing hypotheses about why people object to randomized experiments: 1) People unsurprisingly object to experiments only when they object to a policy or treatment the experiment contains, or 2) people can paradoxically object to experiments even when they approve of implementing either condition for everyone. Using multiple measures of preference and test criteria in five preregistered within-subjects studies with 1,955 participants, we find that people often disapprove of experiments involving randomization despite approving of the policies or treatments to be tested., (Copyright © 2020 the Author(s). Published by PNAS.)

We determined interstellar cosmic ray exposure ages of 40 large presolar silicon carbide grains extracted from the Murchison CM2 meteorite. Our ages, based on cosmogenic Ne-21, range from 3.9 ± 1.6 Ma to ∼3 ± 2 Ga before the start of the Solar System ∼4.6 Ga ago. A majority of the grains have interstellar lifetimes of <300 Ma, which is shorter than theoretical estimates for large grains. These grains condensed in outflows of asymptotic giant branch stars <4.9 Ga ago that possibly formed during an episode of enhanced star formation ∼7 Ga ago. A minority of the grains have ages >1 Ga. Longer lifetimes are expected for large grains. We determined that at least 12 of the analyzed grains were parts of aggregates in the interstellar medium: The large difference in nuclear recoil loss of cosmic ray spallation products 3 He and 21 Ne enabled us to estimate that the irradiated objects in the interstellar medium were up to 30 times larger than the analyzed grains. Furthermore, we estimate that the majority of the grains acquired the bulk of their cosmogenic nuclides in the interstellar medium and not by exposure to an enhanced particle flux of the early active sun., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Compared to clinicians previously surveyed, primary care providers employed in a health system known for clinical genomics were more likely to have ordered or referred a patient for genetic testing, but had only modestly more genetics training and reported similarly low levels of comfort answering patient questions about genetic risk. Most supported population genomic screening, reported willingness to get screened themselves, and judged a hypothetical patient's decision to be screened favorably relative to a similar patient's decision to decline screening. Stakeholder perceptions of the ethical appropriateness of nudging at-risk patients to discuss testing with counselors were mixed., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The breakup of the L-chondrite parent body in the asteroid belt 466 million years (Ma) ago still delivers almost a third of all meteorites falling on Earth. Our new extraterrestrial chromite and 3 He data for Ordovician sediments show that the breakup took place just at the onset of a major, eustatic sea level fall previously attributed to an Ordovician ice age. Shortly after the breakup, the flux to Earth of the most fine-grained, extraterrestrial material increased by three to four orders of magnitude. In the present stratosphere, extraterrestrial dust represents 1% of all the dust and has no climatic significance. Extraordinary amounts of dust in the entire inner solar system during >2 Ma following the L-chondrite breakup cooled Earth and triggered Ordovician icehouse conditions, sea level fall, and major faunal turnovers related to the Great Ordovician Biodiversification Event.

Randomized experiments have enormous potential to improve human welfare in many domains, including healthcare, education, finance, and public policy. However, such "A/B tests" are often criticized on ethical grounds even as similar, untested interventions are implemented without objection. We find robust evidence across 16 studies of 5,873 participants from three diverse populations spanning nine domains-from healthcare to autonomous vehicle design to poverty reduction-that people frequently rate A/B tests designed to establish the comparative effectiveness of two policies or treatments as inappropriate even when universally implementing either A or B, untested, is seen as appropriate. This "A/B effect" is as strong among those with higher educational attainment and science literacy and among relevant professionals. It persists even when there is no reason to prefer A to B and even when recipients are treated unequally and randomly in all conditions (A, B, and A/B). Several remaining explanations for the effect-a belief that consent is required to impose a policy on half of a population but not on the entire population; an aversion to controlled but not to uncontrolled experiments; and a proxy form of the illusion of knowledge (according to which randomized evaluations are unnecessary because experts already do or should know "what works")-appear to contribute to the effect, but none dominates or fully accounts for it. We conclude that rigorously evaluating policies or treatments via pragmatic randomized trials may provoke greater objection than simply implementing those same policies or treatments untested., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)

We present He and Ne isotopes of individual presolar graphite grains from a low-density separate from Orgueil. Two grain mounts were analyzed with the same techniques but in a different sequence: The first one was measured with NanoSIMS followed by noble gas mass spectrometry, and the second one in reverse order. No grain contained 4 He and only one grain on the second mount contained 3 He. On the first mount, the grains had been extensively sputtered with NanoSIMS ion beams prior to noble gas analysis; we found only one grain out of 15 with presolar 22 Ne above detection limit. In contrast, we found presolar 22 Ne in six out of seven grains on the second mount that was not exposed to an ion beam prior to noble gas analysis. All 22 grains on the two mounts were imaged with scanning electron microscopy (SEM) and/or Auger microscopy. We present evidence that this contrasting observation is most likely due to e-beam-induced heating of the generally smaller grains on the first mount during SEM and Auger imaging, and not primarily due to the NanoSIMS analysis. If thermal contact of the grains to the substrate is absent, such that heat can only be dissipated via radiation, then the smaller, sputter-eroded grains are heated to higher temperatures such that noble gases can diffuse out. We discuss possible gas loss mechanisms and suggest solutions to reduce heating during e-beam analyses by minimizing voltages, beam currents, and dwell times. We also found small amounts of 21 Ne in five grains. Using isotope data we determined that the dominant sources of most grains are core-collapse supernovae, congruent with earlier studies of low-density presolar graphite from Murchison. Only two of the grains are most likely from AGB stars, and two others have an ambiguous origin.

Psychologists often note that most people think they are above average in intelligence. We sought robust, contemporary evidence for this "smarter than average" effect by asking Americans in two independent samples (total N = 2,821) whether they agreed with the statement, "I am more intelligent than the average person." After weighting each sample to match the demographics of U.S. census data, we found that 65% of Americans believe they are smarter than average, with men more likely to agree than women. However, overconfident beliefs about one's intelligence are not always unrealistic: more educated people were more likely to think their intelligence is above average. We suggest that a tendency to overrate one's cognitive abilities may be a stable feature of human psychology., Competing Interests: The authors have declared that no competing interests exist.

The 187 Re- 187 Os isotopic systematics of many bulk chondrites plot well beyond analytical uncertainties of a primordial isochron. Limited variations in 187 Os/ 188 Os, coupled with large variations in Re/Os ratios among chondrites, suggest that this apparently open-system behavior is a result of the comparatively recent gain or loss of Re and/or Os. In order to assess whether or not rapid alteration in the terrestrial environment could be responsible for open-system behavior in chondrites, four pieces of the Sutter's Mill meteorite were examined for Os isotopic systematics and abundances of highly siderophile elements. Pieces SM1 and SM2 were collected prior to a rain event, within 2 days of the fall. Pieces SM51 and SM53 were collected after a rain event. There are significant but minor relative and absolute variations in the abundances of the highly siderophile elements, as well as 187 Os/ 188 Os among the four pieces. Rhenium-Os isotopic data for SM1 and SM2 plot within analytical uncertainties of a primordial isochron, while powders made from SM51 and SM53 do not. These results suggest that interactions with rain caused some redistribution of Re, and to a lesser extent Os, within small pieces of the meteorite. Thus, Re-Os isotopic systematics of

Many statistical methods yield the probability of the observed data - or data more extreme - under the assumption that a particular hypothesis is true. This probability is commonly known as 'the' p -value. (Null Hypothesis) Significance Testing ([NH]ST) is the most prominent of these methods. The p -value has been subjected to much speculation, analysis, and criticism. We explore how well the p -value predicts what researchers presumably seek: the probability of the hypothesis being true given the evidence, and the probability of reproducing significant results. We also explore the effect of sample size on inferential accuracy, bias, and error. In a series of simulation experiments, we find that the p -value performs quite well as a heuristic cue in inductive inference, although there are identifiable limits to its usefulness. We conclude that despite its general usefulness, the p -value cannot bear the full burden of inductive inference; it is but one of several heuristic cues available to the data analyst. Depending on the inferential challenge at hand, investigators may supplement their reports with effect size estimates, Bayes factors, or other suitable statistics, to communicate what they think the data say.

Self-enhancement is a positive bias in self-perception, which may imply error. However, conventional measures of self-enhancement are difference scores that do not distinguish a positive bias from a self-enhancement error, that is, they fail to identify those individuals who hold an irrationally or inaccurately positive view of themselves. We propose 2 new measures to separate error from bias. In the domain of personality judgment, we estimate a defensible bias and an enhancement error from individuals' actual and perceived similarity with others. In the domain of performance, we adapt a decision-theoretic framework to distinguish those who falsely believe to be better than average from those who actually are better. We illustrate the properties of these measures in 3 empirical studies and computer simulations. Implausibly high majorities of people consider themselves to be above average on various dimensions., ((c) 2015 APA, all rights reserved).)

Seven particles captured by the Stardust Interstellar Dust Collector and returned to Earth for laboratory analysis have features consistent with an origin in the contemporary interstellar dust stream. More than 50 spacecraft debris particles were also identified. The interstellar dust candidates are readily distinguished from debris impacts on the basis of elemental composition and/or impact trajectory. The seven candidate interstellar particles are diverse in elemental composition, crystal structure, and size. The presence of crystalline grains and multiple iron-bearing phases, including sulfide, in some particles indicates that individual interstellar particles diverge from any one representative model of interstellar dust inferred from astronomical observations and theory., (Copyright © 2014, American Association for the Advancement of Science.)

Doppler weather radar imaging enabled the rapid recovery of the Sutter's Mill meteorite after a rare 4-kiloton of TNT-equivalent asteroid impact over the foothills of the Sierra Nevada in northern California. The recovered meteorites survived a record high-speed entry of 28.6 kilometers per second from an orbit close to that of Jupiter-family comets (Tisserand's parameter = 2.8 ± 0.3). Sutter's Mill is a regolith breccia composed of CM (Mighei)-type carbonaceous chondrite and highly reduced xenolithic materials. It exhibits considerable diversity of mineralogy, petrography, and isotope and organic chemistry, resulting from a complex formation history of the parent body surface. That diversity is quickly masked by alteration once in the terrestrial environment but will need to be considered when samples returned by missions to C-class asteroids are interpreted.

Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.

We measured the elemental compositions of material from 23 particles in aerogel and from residue in seven craters in aluminum foil that was collected during passage of the Stardust spacecraft through the coma of comet 81P/Wild 2. These particles are chemically heterogeneous at the largest size scale analyzed ( approximately 180 ng). The mean elemental composition of this Wild 2 material is consistent with the CI meteorite composition, which is thought to represent the bulk composition of the solar system, for the elements Mg, Si, Mn, Fe, and Ni to 35%, and for Ca and Ti to 60%. The elements Cu, Zn, and Ga appear enriched in this Wild 2 material, which suggests that the CI meteorites may not represent the solar system composition for these moderately volatile minor elements.

Very large collisions in the asteroid belt could lead temporarily to a substantial increase in the rate of impacts of meteorites on Earth. Orbital simulations predict that fragments from such events may arrive considerably faster than the typical transit times of meteorites falling today, because in some large impacts part of the debris is transferred directly into a resonant orbit with Jupiter. Such an efficient meteorite delivery track, however, has not been verified. Here we report high-sensitivity measurements of noble gases produced by cosmic rays in chromite grains from a unique suite of fossil meteorites preserved in approximately 480 million year old sediments. The transfer times deduced from the noble gases are as short as approximately 10(5) years, and they increase with stratigraphic height in agreement with the estimated duration of sedimentation. These data provide powerful evidence that this unusual meteorite occurrence was the result of a long-lasting rain of meteorites following the destruction of an asteroid, and show that at least one strong resonance in the main asteroid belt can deliver material into the inner Solar System within the short timescales suggested by dynamical models.