Using MCMC chain outputs to efficiently estimate Bayes factors

One of the most important methodological problems in psychological research is assessing the reasonableness of null models, which typically constrain a parameter to a specific value such as zero. Bayes factor has been recently advocated in the statistical and psychological literature as a principled means of measuring the evidence in data for various models, including those where parameters are set to specific values. Yet, it is rarely adopted in substantive research, perhaps because of the difficulties in computation. Fortunately, for this problem, the Savage–Dickey density ratio (Dickey & Lientz, 1970) provides a conceptually simple approach to computing Bayes factor. Here, we review methods for computing the Savage–Dickey density ratio, and highlight an improved method, originally suggested by Gelfand and Smith (1990) and advocated by Chib (1995), that outperforms those currently discussed in the psychological literature. The improved method is based on conditional quantities, which may be integrated by Markov chain Monte Carlo sampling to estimate Bayes factors. These conditional quantities efficiently utilize all the information in the MCMC chains, leading to accurate estimation of Bayes factors. We demonstrate the method by computing Bayes factors in one-sample and one-way designs, and show how it may be implemented in WinBUGS.     

Using dynamic field theory to rethink infant habituation

Much of what psychologists know about infant perception and cognition is based on habituation, but the process itself is still poorly understood. Here the authors offer a dynamic field model of infant visual habituation, which simulates the known features of habituation, including familiarity and novelty effects, stimulus intensity effects, and age and individual differences. The model is based on a general class of dynamic (time-based) models that integrate environmental input in varying metric dimensions to reach a single decision. Here the authors provide simulated visual input of varying strengths, distances, and durations to 2 coupled and interacting fields. The 1st represents the activation that drives "looking," and the 2nd, the inhibition that leads to "looking away," or habituation. By varying the parameters of the field, the authors simulate the time course of habituation trials and show how these dynamics can lead to different depths of habituation, which then determine how the system dishabituates. The authors use the model to simulate a set of influential experiments by R. Baillargeon (1986, 1987a, 1987b) using the well-known "drawbridge" paradigm. The dynamic field model provides a coherent explanation without invoking infant object knowledge. The authors show that small changes in model parameters can lead to qualitatively different outcomes. Because in typical infant cognition experiments, critical parameters are unknown, effects attributed to conceptual knowledge may be explained by the dynamics of habituation.     

Plastic deformation behaviour of decagonal Al70Ni15Co15 single quasicrystals

High-temperature deformation experiments have been performed on decagonal Al₇₀Ni₁₅Co₁₅ single quasicrystals at a constant strain rate of 10^-5s^-1 in the temperature range between 700 and 860°C. The samples were deformed in compression with the compression axis in different orientations, parallel to, inclined by 45° and perpendicular to the tenfold symmetry axis. Stress relaxation tests and temperature changes were carried out to determine thermodynamic activation parameters. The flow stress and the activation enthalpy were found to depend on the sample orientation whereas dependences of the activation volume and the stress exponent on the orientation were not observed. Additionally, deformation tests were performed on samples of the basic Co-rich modification of the decagonal phase at the temperature of 860°C in the same three orientations. The deformation behaviours of the two different modifications of the decagonal phase are discussed.     

Phase field modeling of elasto-plastic deformation induced by diffusion controlled growth of a misfitting spherical precipitate

A phase field model accounting for plasticity has been developed using an homogenization scheme for interpolating the constitutive laws within the diffuse interface. The influence of plasticity on the growth of a misfitting spherical precipitate, controlled by solute diffusion has been investigated: plasticity in the matrix slows down the transformation. Moreover, an excellent agreement with the corresponding analytical sharp interface solutions has been achieved.     

The biological foundations of cognitive science

Cognitive Science originated in reactions against behaviorism that were motivated in significant part by the example of the computer. The computer raised the exciting possibility that mind could be understood almost entirely independently of brain: if the operations of the mind are akin to the execution of a program, then almost all the relevant aspects of mind would be captured by that program, independently of whatever was running it, be it transistors or neurons. This presumed independence of cognitive science from biology has waned considerably in recent decades, but in this paper, I argue that there is at least one crucial aspect of biology that has yet to be appreciated for its relevance to mental and other normative processes—the thermodynamics of living systems. In particular, I argue that the emergence of normativity in general—and normative function and representation in particular—depends on special systems that are far from thermodynamic equilibrium; these form the interface between the factual world of atoms and molecules and the normative world of mind. The nature of that emergence, in turn, imposes strong constraints on how the central nervous system functions, and, therefore, on how cognition is realized.     

Amalia X: dialogical sequence analysis as a method in theory-based single case research in psychoanalysis

In this article, Dialogical sequence analysis (DSA) is introduced as a method in theory-based single case research. The structure of article is as follows: first, we will describe briefly the historical background of single case studies and their position as the foundation of psychoanalytic knowledge formation. Secondly, we will describe through Amalia X’s case how one psychoanalytic ‘specimen case’ has been used as a cornerstone for a comprehensive psychoanalytic process research model, the so called ‘Ulm model’. Amalia X is one of the most studied single cases internationally also outside psychoanalytic process study field. Thirdly, we will introduce the central theory and practice of DSA. Fourthly, in the last section of our article, we will show in practice how DSA can be used in the analysis of Amalia’s dream in the session 152.     

Unification of psychophysical phenomena: The complete form of Fechner’s law

Many of the laws and empirical observations of fundamental psychophysics can be unified with a single equation, which has been called the complete form of Fechner’s law. It can be shown that this law embraces both of the commonly used forms: Stevens’s and Fechner’s laws. It assumes one or the other form with appropriate values of the parameters. However, the complete equation confers an advantage beyond simply containing the classical laws. It offers greater flexibility in the representation of experimental data. It is shown that psychophysical phenomena may be represented by any number of triplets of quantities: subjective magnitude of stimulus, subjective just noticeable difference (jnd), and differential threshold. Each of the preceding quantities are functions of the physical magnitude of the stimulus. The investigator has the license to choose two of these quantities in the form he or she thinks is best; the third quantity is determined by the choice of the first two. Thus, for example, different forms of the law of sensation and different forms of the mathematical function for differential threshold may coexist with equal validity.     

Comparison of optimal cutoff points for single and multiple tests in personnel selection

This paper compares the determination of optimal cutoff points for single and multiple tests in the field of personnel selection. Decisional skills of predictor tests composing the multiple test are assumed to be endogenous variables that depend on the cutting points to be set. It is shown how the predictor cutoffs and the collective decision rule are determined dependently by maximizing the multiple test's common expected utility. Our main result specifies the condition that determines the relationship between the optimal cutoff points for single and multiple tests, given the number of predictor tests, the collective decision rule (aggregation procedure of predictor tests' recommendations) and the function relating the tests' decisional skills to the predictor cutoff points. The proposed dichotomous decision-making method is illustrated by an empirical example of selecting trainees by means of the Assessment Center method.     

Can rhesus monkeys spontaneously subtract?

Animals, including pigeons, parrots, raccoons, ferrets, rats, New and Old World monkeys, and apes are capable of numerical computations. Much of the evidence for such capacities is based on the use of techniques that require training. Recently, however, several studies conducted under both laboratory and field conditions have employed methods that tap spontaneous numerical representations in animals, including human infants. In this paper, we present the results of 11 experiments exploring the capacity of semi-free-ranging adult rhesus monkeys to spontaneously compute (i.e. single trial, no training) the outcome of subtraction events. In the basic design, we present one quantity of objects on one stage, a second quantity on a second stage, occlude both stages, and then remove one or no objects from each stage. Having watched these events, a subject is then allowed to approach one stage and eat the food objects behind the occluder. Results show that rhesus monkeys correctly compute the outcome of subtraction events involving three or less objects on each stage, even when the identity of the objects is different. Specifically, when presented with two food quantities, rhesus monkeys select the larger quantity following subtractions of one piece of food from two or three; this preference is maintained when subjects must distinguish food from non-food subtractions, and when food is subtracted from either one or both initial quantities. Furthermore, rhesus monkeys are capable of representing zero as well as equality when two identical quantities are contrasted. Results are discussed in light of recent attempts to determine how number is represented in the brains of animals lacking language.     

A kinematic analysis of age-related changes in grasping to use and grasping to move common objects

Grasping is a complex action which requires high-level motor control. Although the impact of aging on grasping has been investigated in some studies, to date little is known as to how the aging process interacts with the purpose of the movement. The aims of the present study were (i) to investigate the effect of aging on grasping movements, and to explore on how this effect is modulated by (ii) the goal of the task, and by (iii) the characteristics of the target such as its location in the visual field, its orientation and its size. Young and elderly adults were asked to grasp to move or to grasp to use objects of different sizes and orientations, presented either in the central or the peripheral visual field. Movement duration did not differ between the two groups. However, elderly participants required a longer approach phase and showed a different grasping strategy, characterized by larger grip aperture and smaller percentage of wrist rotation in comparison to young adults. Elderly adults showed a decrease in accuracy when grasping objects presented in the peripheral, but not in the central visual field. A similar modulation of the kinematic parameters consisting in longer planning and execution phases in the grasp to use in comparison to the grasp to move condition was observed in both groups, suggesting that the effect of aging might be minimized and compensated in more goal-directed tasks.     

Influence of interface migration during annealing of martensite/austenite mixtures

Tempering of martensite in the absence of carbide precipitation leads to carbon partitioning into retained austenite. If the martensite/austenite interface is assumed to remain stationary during this process, the phase compositions reach a condition that has recently been called constrained carbon equilibrium. If iron atoms are sufficiently mobile at the interface, longer partitioning times may lead to migration of the ferrite/austenite interface. The interface may be expected to move in either direction, depending on the specific details of the phase fractions and compositions controlling the chemical potential of iron at the interface. If interface migration occurs during carbon partitioning, the situation is more complicated and conditions could exist where the interface moves first in one direction and then the other.     

Direct fit of a theoretical model of phase transition in oscillatory finger motions

This paper presents a general method to fit the Schöner‐Haken‐Kelso (SHK) model of human movement phase transitions directly to time series data. A robust variant of the extended Kalman filter technique is applied to the data of a single subject. The options of covariance resetting and iteration within recursion were used to obtain time‐dependent estimates of both the α and β parameters in the SHK model. Comparison between transition onset time and the time at which |β(t|T)/α(t|T)| becomes critical indicates that the transitions are advanced by noise. The method can be extended to handle non‐normal data and generalization across subjects and/or experimental conditions.     

Describing behavior with ratios of count and time

Describing behavior with ratios of count and time is a popular measurement tactic in the field of behavior analysis. The paper examines some count and time ratios in order to determine what about behavior each describes and why one ratio may sometimes be more useful than another. In addition, the paper briefly considers some terminological issues, derived quantities, dimensional analysis, some advantages and disadvantages of ratios, and selection of useful quantities for measurement.     

Metaphysics of quantity and the limit of phenomenal concepts

Quantities like mass and temperature are properties that come in degrees. And those degrees (e.g. 5 kg) are properties that are called the magnitudes of the quantities. Some philosophers talk about magnitudes of phenomenal qualities as if some of our phenomenal qualities are quantities. The goal of this essay is to explore the anti-physicalist implication of this apparently innocent way of conceptualizing phenomenal quantities. I will first argue for a metaphysical thesis about the nature of magnitudes based on Yablo’s proportionality requirement of causation. Then, I will show that, if some phenomenal qualities are indeed quantities, there can be no demonstrative concepts about some of our phenomenal feelings. That presents a significant restriction on the way physicalists can account for the epistemic gap between the phenomenal and the physical. I’ll illustrate the restriction by showing how that rules out a popular physicalist response to the Knowledge Argument.     

Neural Mechanisms of Visual Feature Binding Investigated with Microelectrodes and Models

A single object generally activates neurones in many visual cortical areas corresponding to a distributed representation of its features. Itis still under debate how the distributed representation of an objectis bound intoa coherent whole and how unrelated features are separated. Synchronization of neural signals has been proposed to code spatial feature binding, supported by the discovery of synchronized assemblies in visual cortex. Synchronizations are either fast oscillatory (30–90 Hz) cortically generated events, or non-rhythmical stimulus-locked responses, depending on the visual stimulation. The cortical range over which synchronizations occur, transformed to visual space, is generally several times larger than the classical receptive fields (CRF) of neurones in lower visual cortex areas. However, the cortical regions synchronized by fastoscillations do notspan the representational range of larger objects but only parts of it. To relate such restricted segments to perceptual processes the concept of the association field (AF) of local neural assemblies was introduced in accordance with CRFs of single neurones. Here an AF is composed of the aggregate of CRFs of an assembly engaged in a common synchronized state. Itis argued thatspatial continuity of an object is coded by a continuum of overlapping AFs, that is, by overlapping regions of phase coupled neurones. Hence, object continuity would be represented by phase continuity. Besides feature binding, feature separation is necessary for scene segmentation. Separation may be coded by functional decoupling causing uncorrelated activities or by mutual inhibition leading to alternating activations in assemblies of separate representations. A third temporal coding aspect is temporal segmentation by the shortactivation-inhibition cycles of fast oscillations orshorttransientstimulus-locked responses, which may preventperceptual “smearing” by interrupting the flow of visual information into precisely defined frames. The presentpaperalso aims atrelating signals of stimulus dependentsynchronization and desynchronization with basic neural mechanisms and circuits. Finally, the synchronization hypothesis is critically discussed with respect to contradictory psychophysical work and supportive new recording results, including evidence for perception-related synchronizations.     

Quantity judgments of auditory and visual stimuli by chimpanzees (Pan troglodytes)

Many species can choose between two visual sets of stimuli on the basis of quantity. This is true when sets are both visible, or are presented one set at a time or even one item at a time. However, we know comparatively little about how well nonhuman animals can compare auditory quantities. Here, three chimpanzees (Pan troglodytes) chose between two sets of food items when they only heard each item fall into different containers rather than seeing those items. This method prevented the chimpanzees from summing the amount of visible food they saw because there were no visual cues. Chimpanzees performed well, and their performance matched that of previous experiments with regard to obeying Weber's law. They also performed well with comparisons between a sequentially presented auditory set and a fully visible set, demonstrating that duration of presentation was not being used as a cue. In addition, they accommodated empty sets into these judgments, although not perfectly. Thus, chimpanzees can judge auditory quantities in flexible ways that show many similarities to how they compare visual quantities.     

Universality of the reversal transition in growth phenomena of molecular crystals

ABSTRACT

The fundamental origin of the reversal transition during crystal growth has been investigated by Monte Carlo simulations. Evidence is provided supporting the geometrical nature of the transition, arising from the broken translational invariance at the growth front and the interactions of multipoles of opposed parity. The range of interactions, the details of the force field and model are irrelevant to the occurrence and only determine the functional behaviour of the relevant physical quantities like the localisation of the critical point and the morphology of the phase diagram.     

近红外光学成像在社会认知神经科学中的应用

社会认知神经科学是运用认知神经科学的研究手段,探讨社会科学问题与理论的多学科交叉领域。近来,功能性近红外光学成像技术(functional near-infrared spectroscopy,fNIRS)凭借生态效度高、成像安全、对头动耐受性高、成本低等优势,成为了该领域新兴的热点技术。无论是在婴儿发育和社会经济决策的单脑研究中,还是在人际互动的多脑研究中,它都有广泛应用。未来近红外光学成像的应用可以向多脑神经反馈、脑机接口技术、设备无线化和多模态成像做进一步探索。     

Addendum to "Summation in the chimpanzee (Pan troglodytes)"

Rumbaugh, Savage-Rumbaugh, and Hegel (1987) reported that two chimpanzees (Pan troglodytes) could select, with better than 90% accuracy, the greater of two paired quantities of chocolate chips. In that study, no one quantity of chocolates (from 0 through 5) was used in both pairs on a given trial. We investigated the effect of having one quantity in common (CQ) in both pairs. Whether the other quantities (OQs) of chocolates were both less than or greater than the CQ, summation still occurred. Accuracy was primarily a function of the ratios of sums to be differentiated. This finding substantiated the earlier conclusion that summation was based on both quantities of each pair and not on some simpler process such as the avoidance of the tray with the smallest single amount or selection of the tray with the single largest amount.     

A web-based interface to calculate phonotactic probability for words and nonwords in English.

Phonotactic probability refers to the frequency with which phonological segments and sequences of phonological segments occur in words in a given language. We describe one method of estimating phonotactic probabilities based on words in American English. These estimates of phonotactic probability have been used in a number of previous studies and are now being made available to other researchers via a Web-based interface. Instructions for using the interface, as well as details regarding how the measures were derived, are provided in the present article. The Phonotactic Probability Calculator can be accessed at http://www.people.ku.edu/-mvitevit/PhonoProbHome.html.