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931.
This study uses within-study comparisons to assess the relative importance of covariate choice, unreliability in the measurement of these covariates, and whether regression or various forms of propensity score analysis are used to analyze the outcome data. Two of the within-study comparisons are of the four-arm type, and many more are of the three-arm type. To examine unreliability, simulations of differences in reliability are deliberately introduced into the 2 four-arm studies. Results are similar across the samples of studies reviewed with their wide range of non-experimental designs and topic areas. Covariate choice counts most, unreliability next most, and the mode of data analysis hardly matters at all. Unreliability has larger effects the more important a covariate is for bias reduction, but even so the very best covariates measured with a reliability of only .60 still do better than substantively poor covariates that are measured perfectly. Why regression methods do as well as propensity score methods used in several different ways is a mystery still because, in theory, propensity scores would seem to have a distinct advantage in many practical applications, especially those where functional forms are in doubt. 相似文献
932.
Peter J. Markie 《Philosophical Studies》2013,163(1):271-290
Rational intuitions involve a particular form of understanding that gives them a special epistemic status. This form of understanding and its epistemic efficacy are not explained by several current theories of rational intuition, including Phenomenal Conservatism (Huemer, Skepticism and the veil of perception, 2001; Ethical intuitionism, 2005; Philos Phenomenol Res 74:30–55, 2007), Proper Functionalism (Plantinga, Warrant and proper function, 1993), the Competency Theory (Bealer Pac Philos Q 81:1–30, 2000; Sosa, A virtue epistemology, 2007) and the Direct Awareness View (Conee, Philos Phenomenol Res 4:847–857, 1998; Bonjour, In defense of pure reason, 1998). Some overlook it; others try to account for it but fail. We can account for the role of understanding in rational intuition by returning to the view of some of the early Rationalists, e.g. Descartes and Leibniz. While that view carries a prohibitive cost, it does contain an insight that may help us solve the problem of giving understanding its due. 相似文献
933.
Previous research has identified a subgroup of socially anxious adults who are both anxious and impulsive. To date, however, this subgroup has not been identified in adolescence. Therefore, in this study we aimed to identify this subgroup in a sample of adolescents. In addition, we hypothesized that this subgroup would be higher on problem behaviors, and that these processes would be moderated by gender. We used longitudinal data from 714 adolescents who were in the 7th and 8th grades at Time 1. They were followed annually for three years. Cluster analyses identified an anxious‐inhibited subgroup as well as an anxious‐impulsive subgroup in early adolescence (Time 1). The socially anxious‐impulsive adolescent boys were generally higher on both intoxication frequency and delinquency compared with all other adolescents in all clusters at each time point. Findings suggest that social anxiety subgroups may differ on problem behavior, and that early detection of an anxious‐impulsive subgroup may be important to prevent maladjustment, especially for adolescent boys. 相似文献
934.
We apply the Hawkes process to the analysis of dyadic interaction. The Hawkes process is applicable to excitatory interactions, wherein the actions of each individual increase the probability of further actions in the near future. We consider the representation of the Hawkes process both as a conditional intensity function and as a cluster Poisson process. The former treats the probability of an action in continuous time via non-stationary distributions with arbitrarily long historical dependency, while the latter is conducive to maximum likelihood estimation using the EM algorithm. We first outline the interpretation of the Hawkes process in the dyadic context, and then illustrate its application with an example concerning email transactions in the work place. 相似文献
935.
The axiom of choice ensures precisely that, in ZFC, every set is projective: that is, a projective object in the category of sets. In constructive ZF (CZF) the existence of enough projective sets has been discussed as an additional axiom taken from the interpretation of CZF in Martin-Löf’s intuitionistic type theory. On the other hand, every non-empty set is injective in classical ZF, which argument fails to work in CZF. The aim of this paper is to shed some light on the problem whether there are (enough) injective sets in CZF. We show that no two element set is injective unless the law of excluded middle is admitted for negated formulas, and that the axiom of power set is required for proving that “there are strongly enough injective sets”. The latter notion is abstracted from the singleton embedding into the power set, which ensures enough injectives both in every topos and in IZF. We further show that it is consistent with CZF to assume that the only injective sets are the singletons. In particular, assuming the consistency of CZF one cannot prove in CZF that there are enough injective sets. As a complement we revisit the duality between injective and projective sets from the point of view of intuitionistic type theory. 相似文献
936.
Modal dependence logic was introduced recently by Väänänen. It enhances the basic modal language by an operator = (). For propositional variables p 1, . . . , p n , = (p 1, . . . , p n-1, p n ) intuitively states that the value of p n is determined by those of p 1, . . . , p n-1. Sevenster (J. Logic and Computation, 2009) showed that satisfiability for modal dependence logic is complete for nondeterministic exponential time. In this paper we consider fragments of modal dependence logic obtained by restricting the set of allowed propositional connectives. We show that satisfiability for poor man’s dependence logic, the language consisting of formulas built from literals and dependence atoms using ${\wedge, \square, \lozenge}$ (i. e., disallowing disjunction), remains NEXPTIME-complete. If we only allow monotone formulas (without negation, but with disjunction), the complexity drops to PSPACE-completeness. We also extend Väänänen’s language by allowing classical disjunction besides dependence disjunction and show that the satisfiability problem remains NEXPTIME-complete. If we then disallow both negation and dependence disjunction, satisfiability is complete for the second level of the polynomial hierarchy. Additionally we consider the restriction of modal dependence logic where the length of each single dependence atom is bounded by a number that is fixed for the whole logic. We show that the satisfiability problem for this bounded arity dependence logic is PSPACE-complete and that the complexity drops to the third level of the polynomial hierarchy if we then disallow disjunction. In this way we completely classify the computational complexity of the satisfiability problem for all restrictions of propositional and dependence operators considered by Väänänen and Sevenster. 相似文献
937.
Fabienne Peter 《Synthese》2013,190(7):1253-1266
Collective deliberation is fuelled by disagreements and its epistemic value depends, inter alia, on how the participants respond to each other in disagreements. I use this accountability thesis to argue that deliberation may be valued not just instrumentally but also for its procedural features. The instrumental epistemic value of deliberation depends on whether it leads to more or less accurate beliefs among the participants. The procedural epistemic value of deliberation hinges on the relationships of mutual accountability that characterize appropriately conducted deliberation. I will argue that it only comes into view from the second-person standpoint. I shall explain what the second-person standpoint in the epistemic context entails and how it compares to Stephen Darwall’s interpretation of the second-person standpoint in ethics. 相似文献
938.
Although punishment and forgiveness frequently are considered to be opposites, in the present paper we propose that victims who punish their offender are subsequently more likely to forgive. Notably, punishment means that victims get justice (i.e. just deserts), which facilitates forgiveness. Study 1 reveals that participants were more likely to forgive a friend's negligence after being primed with punishment than after being primed with inability to punish. In Study 2, participants were more forgiving towards a criminal offender if the offender was punished by a judge than if the offender escaped punishment, a finding that was mediated by the just deserts motive. Study 3 was in the context of actual recalled ongoing interpersonal relations and revealed that punishment predicted forgiveness indirectly via just deserts, not via victims' vengeful motivations. It is concluded that punishment facilitates forgiveness because of its capacity to restore a sense of justice. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
939.
Peter J. Lewis 《Synthese》2013,190(18):4009-4022
The Doomsday Argument and the Simulation Argument share certain structural features, and hence are often discussed together (Bostrom 2003, Are you living in a computer simulation, Philosophical Quarterly, 53:243–255; Aranyosi 2004, The Doomsday Simulation Argument. Or why isn’t the end nigh, and you’re not living in a simulation, http://philsci-archive.pitt.edu/190/; Richmond 2008, Doomsday, Bishop Ussher and simulated worlds, Ratio, 21:201–217; Bostrom and Kulczycki 2011 A patch for the Simulation Argument, Analysis, 71:54–61). Both are cases where reflecting on one’s location among a set of possibilities yields a counter-intuitive conclusion—in the first case that the end of humankind is closer than you initially thought, and in the second case that it is more likely than you initially thought that you are living in a computer simulation. Indeed, the two arguments do have some structural similarities. But there are also significant disanalogies between the two arguments, and I argue that these disanalogies mean that the Simulation Argument succeeds and the Doomsday Argument fails. 相似文献
940.