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Garbarino et al. (J Econ Sci Assoc. https://doi.org/10.1007/s40881-018-0055-4, 2018) describe a new method to calculate the probability distribution of the proportion of lies told in “coin flip” style experiments. I show that their estimates and confidence intervals are flawed. I demonstrate two better ways to estimate the probability distribution of what we really care about—the proportion of liars—and I provide R software to do this.
This editorial considers the value and nature of academic psychiatry by asking what defines the specialty and psychiatrists as academics. We frame academic psychiatry as a way of thinking that benefits clinical services and discuss how to inspire the next generation of academics.
Several recent studies have demonstrated how large-scale vortices may arise spontaneously in rotating planar convection. Here, we examine the dynamo properties of such flows in rotating Boussinesq convection. For moderate values of the magnetic Reynolds number ($100\lesssim Rm\lesssim 550$, with $Rm$ based on the box depth and the convective velocity), a large-scale (i.e. system-size) magnetic field is generated. The amplitude of the magnetic energy oscillates in time, nearly out of phase with the oscillating amplitude of the large-scale vortex. The large-scale vortex is disrupted once the magnetic field reaches a critical strength, showing that these oscillations are of magnetic origin. The dynamo mechanism relies on those components of the flow that have length scales lying between that of the large-scale vortex and the typical convective cell size; smaller-scale flows are not required. The large-scale vortex plays a crucial role in the magnetic induction despite being essentially two-dimensional; we thus refer to this dynamo as a large-scale-vortex dynamo. For larger magnetic Reynolds numbers, the dynamo is small scale, with a magnetic energy spectrum that peaks at the scale of the convective cells. In this case, the small-scale magnetic field continuously suppresses the large-scale vortex by disrupting the correlations between the convective velocities that allow it to form. The suppression of the large-scale vortex at high $Rm$ therefore probably limits the relevance of the large-scale-vortex dynamo to astrophysical objects with moderate values of $Rm$, such as planets. In this context, the ability of the large-scale-vortex dynamo to operate at low magnetic Prandtl numbers is of great interest.
The signing of international treaties is usually considered insignificant for international legal cooperation. Accordingly, International Relations theorists have paid it little attention. We show in this paper how and why treaty signature matters for the ultimate decision to ratify an international treaty. We argue that when multiple well-informed actors publicly sign an international treaty, this can provide a strong signal of issue importance to domestic veto players, and in turn may persuade them to ratify the treaty. We formalize this argument in a two-level signaling game, and test it on a data set of 126 international environmental agreements. We find that treaties are more likely to be ratified when their signatories include countries with high levels of general or issue-specific knowledge.
Using numerical simulations of rapidly rotating Boussinesq convection in a Cartesian box, we study the formation of long-lived, large-scale, depth-invariant coherent structures. These structures, which consist of concentrated cyclones, grow to the horizontal scale of the box, with velocities significantly larger than the convective motions. We vary the rotation rate, the thermal driving and the aspect ratio in order to determine the domain of existence of these large-scale vortices (LSV). We find that two conditions are required for their formation. First, the Rayleigh number, a measure of the thermal driving, must be several times its value at the linear onset of convection; this corresponds to Reynolds numbers, based on the convective velocity and the box depth, $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}{\gtrsim }100$. Second, the rotational constraint on the convective structures must be strong. This requires that the local Rossby number, based on the convective velocity and the horizontal convective scale, ${\lesssim }0.15$. Simulations in which certain wavenumbers are artificially suppressed in spectral space suggest that the LSV are produced by the interactions of small-scale, depth-dependent convective motions. The presence of LSV significantly reduces the efficiency of the convective heat transport.
The complexities of ultracool atmospheres are best confronted by observations of ultracool dwarfs (UCDs) with well known physical properties (luminosity, mass, Teff, log(g), [M/H]), so-called “benchmark objects.” We present two discoveries from a new WISE+2MASS search for benchmark wide companions to Hipparcos and Gliese stars. This survey combination provides a powerful tool to confirm new companions using color-magnitude and common proper motion selections, and also yield full NIR-MIR measurements of the ultracool emission. These primary companions are providing important constraints on the age and composition of the benchmark brown dwarf, and the new discoveries add to our growing population of benchmarks that is providing crucial tests of ultracool physics.
Edited by
Alex S. Evers, Washington University School of Medicine, St Louis,Mervyn Maze, University of California, San Francisco,Evan D. Kharasch, Washington University School of Medicine, St Louis
Are voters sophisticated? Rational choice theories of voting assume they are. Students of voting behaviour are more doubtful. This article examines voting in a particularly demanding setting: direct democratic elections in which two competing proposals are on the ballot. It develops a spatial model of voting and proposal qualification with competing proposals. If voters are naïve, then competing proposals can be used to block the direct democratic route to change, but, if voters vote strategically, competing proposals can bring outcomes closer to the median voter. Voting intention data from California polls provide evidence that some votes are cast strategically even in these demanding circumstances. However, the level of strategic voting appears to be affected by the nature of the election campaign.
This study compares the clinical and social outcome for 2 cohorts of patients who had a first admission for schizophrenia 4 years earlier. One cohort was treated in a psychiatric unit attached to a teaching district general hospital (DGH(T)), while the other was treated at an area mental hospital (AMH) with modern rehabilitation facilities. The clinical outcome for the 2 cohorts was broadly similar, but the DGH(T) imposed less of a strain on relatives, and was associated with less unmet need. The DGH unit tended to have significantly shorter durations of stay for its patients, so that its total hospital costs were less than those for the AMH despite higher unit costs. The cost benefit analysis shows that, where these particular patients are concerned, the DGH(T) unit is economically superior to the AMH despite the fact that it supports a large teaching staff, and that these economic advantages are accompanied by various non-monetary advantages.
Hallucinations have been found associated with false detection or false recognition of acoustic/verbal material in several studies. We investigated whether they were also linked with false recognition of pictures. Furthermore, an association between hallucinations and deficits in remembering temporal context was observed in previous research on schizophrenia. We investigated whether the association extends to deficits in remembering spatial context. Forty-one patients with schizophrenia underwent a visual memory task. Sixteen mixed black-and-white and colored pictures were presented at different locations. Participants had to recognize the pictures among distractors, then to recall the spatial context of the presentation of the target pictures. Results showed that auditory hallucinations were associated with poor recognition of the colored pictures. When recognition efficiency and negative symptoms were statistically controlled, auditory hallucinations were also associated with increased response bias toward false recognition of nontarget pictures, and with errors in remembering the spatial context. No associations with visual hallucinations emerged. Anhedonia was associated with response bias, in the direction opposite to that of hallucinations. In conclusion, the association between hallucinations and response bias extends across modalities to picture recognition. The association between hallucinations and temporal context impairment extends to spatial context. (JINS, 2007, 13, 832–838.)
The response to strength training varies widely between individuals and is considerably influenced by genetic variables, which until now, have remained unidentified. The deletion (D), rather than the insertion (I), variant of the human angiotensin-converting enzyme (ACE) genotype is an important factor in the hypertrophic response of cardiac muscle to exercise and could also be involved in skeletal muscle hypertrophy - an important factor in the response to functional overload. Subjects were 33 healthy male volunteers with no experience of strength training. We examined the effect of ACE genotype upon changes in strength of quadriceps muscles in response to 9 weeks of specific strength training (isometric or dynamic). There was a significant interaction between ACE genotype and isometric training with greater strength gains shown by subjects with the D allele (mean ± S.E.M.: II, 9.0 ± 1.7 %; ID, 17.6 ± 2.2 %; DD, 14.9 ± 1.3 %, ANOVA, P0.05). A consistent genotype and training interaction (IDDDII) was observed across all of the strength measures, and both types of training. ACE genotype is the first genetic factor to be identified in the response of skeletal muscle to strength training. The association of the ACE I/D polymorphism with the responses of cardiac and skeletal muscle to functional overload indicates that they may share a common mechanism. These findings suggest a novel mechanism, involving the renin-angiotensin system, in the response of skeletal muscle to functional overload and may have implications for the management of conditions such as muscle wasting disorders, prolonged bed rest, ageing and rehabilitation, where muscle weakness may limit function. Experimental Physiology (2000) 85.5, 575-579.
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