Local rather than global processing of visual arrays in numerosity discrimination by pigeons (Columba livia)

A series of experiments investigated which stimulus properties pigeons use when they discriminate pairs of visual arrays that differ in numerosity. Transfer tests with novel stimuli confirmed that the birds’ choices were based on relative differences in numerosity. However, pigeons differed from other species in the non-numerical cues that affected their choices. In human and non-human primates, numerical discrimination is often influenced by continuous variables such as surface area or overall stimulus brightness. Pigeons showed little evidence of using those cues, even when summed area and brightness had been correlated with numerosity differences and reward outcome. But when array-element sizes were asymmetrically distributed across numerosities, the birds readily utilized information about item sizes as an additional discriminative cue. These novel results are discussed in relation to pigeons’ tendency to focus on local, rather than global dimensions when they process other non-numerical complex visual stimuli. The findings suggest there may be inter-specific differences in the type of perceptual information that provides the input stage for mechanisms underlying numerical processing. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

论德性与独立的实践推理者

德性对于人的兴盛是必不可少的。没有道德德性,我们就不能实现从动物性理智到实践推理的转变,其次不能继续有推理的实践;如果不发展某种程度的德性,我们就不能适当地关怀和教育他人。所以,德性必须首先获得,然后才能维持在推理的实践之中。最后,我们在成为实践推理之后,我们仍然需要他人的维护,这种需要同时也是一种对德性的需要。     

The Perceiver's Share: Realism, Scepticism, and Response Dependence

Abstract: Response‐dispositional (RD) properties are standardly defined as those that involve an object's appearing thus or thus to some perceptually well‐equipped observer under specified epistemic conditions. The paradigm instance is that of colour or other such Lockean “secondary qualities”, as distinct from those—like shape and size—that pertain to the object itself, quite apart from anyone's perception. This idea has lately been thought to offer a promising alternative to the deadlocked dispute between hard‐line ‘metaphysical’ realists and subjectivists, projectivists, social constructivists, or hard‐line anti‐realists. A chief source text is Plato's Euthyphro, where the issue is posed in ethical terms: do the gods infallibly approve virtuous acts on account of their divine moral omniscience or are virtuous acts just those the gods approve? Among the areas proposed as amenable to an RD approach are epistemology, ethics, political theory, and philosophy of mathematics. It is claimed that by making due allowance for the involvement of normalised or optimised human responses one can steer a course between the twin poles of an objectivist realism that places truth beyond our cognitive grasp and an epistemic conception that confines truth within the limits of humanly attainable proof, knowledge, or verification. Here I argue—on the contrary—that RD approaches can be shown to offer nothing more than a variant of the same old realist versus anti‐realist dilemma. That is, they work out either as a trivial (tautologous) claim that ‘truth’ simply equates with ‘best judgement’ in the ideal (quasi‐objective) limit or as the claim—advanced by anti‐realists like Michael Dummett—that we cannot form any adequate conception of objective (recognition‐transcendent) truths. After looking at this issue in various contexts of debate, I conclude that one useful (if pyrrhic) outcome is to demonstrate the non‐availability of any middle‐ground stance. We are left with the strictly unavoidable choice between a realist or objectivist approach and one that assimilates truth to the consensus of accredited best opinion. This latter amounts to a roundabout, elaborately qualified version of the anti‐realist case.     

高职生自主学习能力与网络依赖程度关系的研究

在问卷调查法的基础上,本研究对高职生自主学习能力与网络依赖程度进行多种维度的相关分析,并通过多重线性回归分别对突出影响网络依赖及其四种维度的自主学习因子进行考察.结果表明:高职生自主学习能力和网络依赖程度之间存在十分密切的关系,其中学习策略分量表中的学习求助因子和学习管理因子对高职生的网络依赖有最大的影响.     

Trust,risk, and the social contract

The problem of trust is discussed in terms of David Hume’s meadow-draining example. This is analyzed in terms of rational choice, evolutionary game theory and a dynamic model of social network formation. The kind of explanation that postulates an innate predisposition to trust is seen to be unnecessary when social network dynamics is taken into account.     

Local and global processing: observations from a remote culture

In Experiment 1, a normal adult population drawn from a remote culture (Himba) in northern Namibia made similarity matches to [Navon, D. (1977). Forest before trees: The precedence of global features in visual perception. Cognitive Psychology, 9, 353-383] hierarchical figures. The Himba showed a local bias stronger than that has been previously observed in any other non-clinical human population. However, in Experiment 2, their recognition of normal or distorted ("Thatcherized") faces did not appear to have been affected by their attention to detail as has been suggested for autistic populations. The data are consistent with a cultural/experiential origin for population differences in local processing and suggest that attention to the local and global properties of stimuli may differ for hierarchical figures and faces.     

Reference dependence in iterative choices

Valuation of goods often proceeds from a series of hypothetical pairwise choices. We examine reference dependence on the outcome of such evaluations in a large-scale study in which respondents make a series of choices between areas that differ on cost of living and the quality of lakes and rivers. We uncover three substantial reference effects. First, we find that respondents’ choices are altered by being told the national value of water quality. For these people, consistent with prospect theory, changes in water quality below the 65% referenced national standard are treated as losses and given more weight while identical changes above 65% are treated as gains and given less weight. Second, we find that the sequence of iterative choices matters in a surprising way. The iterations proceed by encouraging switching either by degrading the chosen alternative or improving the item chosen. We show that improving the item not chosen produces the greatest switching, a result consistent with prospect theory, but only if the item changed in the iteration becomes the reference alternative. Finally, we find a strong starting reference effect. That is, we show that the trade-off in the first choice reflected in the change in cost of living divided by the change in water quality has a substantial impact on the final valuation. We assess the relative impact of these three reference effects and suggest ways of dealing with them for valuation of non-market goods.     

大学新生的羞怯、自尊与网络依赖的关系：交叉滞后分析

对361名大一新生进行为期3个月的追踪测量,以考察羞怯、自尊与网络依赖的发展变化及相互关系。结果发现：（1）大一新生的羞怯、自尊和网络依赖的水平具有一定程度的横向稳定性。（2）羞怯与网络依赖正相关,自尊与网络依赖负相关。（3）T1的网络依赖正向预测T2的羞怯,T2的羞怯正向预测T3的网络依赖;T1和T2的网络依赖分别负向预测T2和T3的自尊。结论：羞怯与网络依赖之间存在恶性循环,并且网络依赖会导致自尊水平的下降。     

Model Implied Instrumental Variables (MIIVs): An Alternative Orientation to Structural Equation Modeling

Few dispute that our models are approximations to reality. Yet when it comes to structural equation models (SEMs), we use estimators that assume true models (e.g. maximum likelihood) and that can create biased estimates when the model is inexact. This article presents an overview of the Model Implied Instrumental Variable (MIIV) approach to SEMs from Bollen (1996). The MIIV estimator using Two Stage Least Squares (2SLS), MIIV-2SLS, has greater robustness to structural misspecifications than system wide estimators. In addition, the MIIV-2SLS estimator is asymptotically distribution free. Furthermore, MIIV-2SLS has equation-based overidentification tests that can help pinpoint misspecifications. Beyond these features, the MIIV approach has other desirable qualities. MIIV methods apply to higher order factor analyses, categorical measures, growth curve models, dynamic factor analysis, and nonlinear latent variables. Finally, MIIV-2SLS permits researchers to estimate and test only the latent variable model or any other subset of equations. In addition, other MIIV estimators beyond 2SLS are available. Despite these promising features, research is needed to better understand its performance under a variety of conditions that represent empirical applications. Empirical and simulation examples in the article illustrate the MIIV orientation to SEMs and highlight an R package MIIVsem that implements MIIV-2SLS.     

Nonlinear approach to study the acute effects of static and dynamic stretching on local dynamic stability in lower extremity joint kinematics and muscular activity during pedalling

Researchers have reported contradictory results on the effect of static and dynamic stretching on subsequent performance. Due to the importance of performance through static and dynamic stretching, the aim of this study is to investigate the acute effects of static and dynamic stretching protocols on local dynamic stability in lower extremity joint kinematics and muscular activities during pedalling using a nonlinear dynamics approach. Using a randomised crossover trial design, fifteen active males participated voluntarily in this research (mass: 69.02 ± 10.52 kg, height: 174.00 ± 6.74 cm, and age: 21.20 ± 1.47 years) and completed a pedalling trial in situations of without stretching (WS), after static (SS), and dynamic stretching (DS) of lower extremity. The lower extremity joint angles in the sagittal plane and the electrical activity of soleus, gastrocnemius medialis, tibialis anterior, vastus medialis, biceps femoris, and rectus femoris muscles were collected during 30 pedalling cycles at 70 rates per minute. The results of the repeated measure ANOVA indicated that the knee and ankle angle largest LyE was significantly lower in DS compared to WS and SS. The largest LyE in muscle activity is also significantly lower for all the muscles after DS compared to WS and SS (P ≤ 0.05). Regarding the positive effects of DS on the joints and the muscle activity local dynamic stability, it is suggested to use DS than SS in the warm-up program before repetitive activities like pedalling.