A dynamic theory of proportional judgment: Context and judgment of length, heaviness, and roughness.

Ss judged the length of lines, the heaviness of weights, or the roughness of sandpaper in 2 conditions. In one condition, they were instructed to make all their judgments relative to a long-term reference point, which consisted of a reference response and sensation. In the other condition, they were told to use a short-term reference point, namely, the response and sensation of the previous trial. A dynamic model of proportional judgment (L. T. DeCarlo; see record 1993-12129-001) predicts that the autocorrelation of successive responses will be larger for the latter instructions. This prediction was confirmed for the 3 continua. In addition, fits of a recently proposed dynamic regression model show that there is little or no effect of the previous stimulus intensity on the current response, whereas the results for an earlier model suggest a large contrast effect. The theory and experiments provide insight into judgmental and sensory processes in magnitude scaling. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An application of signal detection theory with finite mixture distributions to source discrimination.

A mixture extension of signal detection theory is applied to source discrimination. The basic idea of the approach is that only a portion of the sources (say A or B) of items to be discriminated is encoded or attended to during the study period. As a result, in addition to 2 underlying probability distributions associated with the 2 sources, there is a 3rd distribution that represents items for which sources were not attended to. Thus, over trials, the observed response results from a mixture of an attended (A or B) distribution and a nonattended distribution. The situation differs in an interesting way from detection in that, for detection, there is mixing only on signal trials and not on noise trials, whereas for discrimination, there is mixing on both A and B trials. Predictions of the mixture model are examined for data from several recent studies and in a new experiment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Process dissociation and mixture signal detection theory.

The process dissociation procedure was developed in an attempt to separate different processes involved in memory tasks. The procedure naturally lends itself to a formulation within a class of mixture signal detection models. The dual process model is shown to be a special case. The mixture signal detection model is applied to data from a widely analyzed study. The results suggest that a process other than recollection may be involved in the process dissociation procedure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Optical Flow Constraints on Deformable Models with Applications to Face Tracking

Optical flow provides a constraint on the motion of a deformable model. We derive and solve a dynamic system incorporating flow as a hard constraint, producing a model-based least-squares optical flow solution. Our solution also ensures the constraint remains satisfied when combined with edge information, which helps combat tracking error accumulation. Constraint enforcement can be relaxed using a Kalman filter, which permits controlled constraint violations based on the noise present in the optical flow information, and enables optical flow and edge information to be combined more robustly and efficiently. We apply this framework to the estimation of face shape and motion using a 3D deformable face model. This model uses a small number of parameters to describe a rich variety of face shapes and facial expressions. We present experiments in extracting the shape and motion of a face from image sequences which validate the accuracy of the method. They also demonstrate that our treatment of optical flow as a hard constraint, as well as our use of a Kalman filter to reconcile these constraints with the uncertainty in the optical flow, are vital for improving the performance of our system.     

Shape evolution with structural and topological changes usingblending

This paper describes a framework for the estimation of shape from sparse or incomplete range data. It uses a shape representation called blending, which allows for the geometric combination of shapes into a unified model - selected regions of the component shapes are cut-out and glued together. Estimation of shape by this representation is realized using a physics-based framework, and it also includes a process for deciding how to adapt the structure and topology of the model to improve the fit. The blending representation helps avoid abrupt changes in model geometry during fitting by allowing the smooth evolution of the shape, which improves the robustness of the technique. We demonstrate this framework with a series of experiments showing its ability to automatically extract structured representations from range data given both structurally and topologically complex objects     

Rotor-blade modulation on antenna amplitude pattern andpolarization: predictions and measurements

The rotation of lift- and thrust-generating airfoils causes a periodic variation in aircraft communication signals. This effect is called rotor-blade modulation (RBM). The RBM on the radiation characteristics of helicopter-mounted antennas are predicted using the uniform theory of diffraction (UTD) and the finite-difference time-domain (FDTD) method and are compared with scale model measurements and full-scale in-flight measurements. In addition, the effects of electric field polarization on RBM are studied using the FDTD     

Time allocation in carpenter ants (Componotus herculeanus).

In three experiments we examined the time allocations of carpenter ants (Componotus herculeanus) that chose between different rates of brief deliveries of the odor of peppermint oil, an aversive stimulus for ants. The odor deliveries were programmed by two variable-time schedules that ran either simultaneously or successively. In both cases the relative time allocations varied systematically with respect to the relative local (number per time) rates of odor delivery. In addition, the relative time allocations were more extreme when the two schedules ran simultaneously instead of successively. Similar results were found for rats that chose between different rates of shock delivery (M. Z. Deluty and R. M. Church; see record 1979-12724-001). We suggest that one process that underlies the time allocations of both species is the elicitation of activity by the aversive stimuli. Relative differences in the time allocations of ants and rats across the two types of schedules may also reflect a species difference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children's influence in the marital relationship.

In a 3-wave longitudinal study, the authors tested hypotheses regarding children's influence on the marital relationship, examining relations between interparental discord and children's negative emotional reactivity, agentic behavior, dysregulated behavior, and psychosocial adjustment. Participants were 232 cohabiting mothers and fathers who completed questionnaires and a marital conflict resolution task. Consistent with theory, interparental discord related to children's negative emotional reactivity, which in turn related to children's agentic and dysregulated behavior. Agentic behavior related to decreases in interparental discord, whereas dysregulated behavior related to increases in discord and elevations in children's adjustment problems. Person-oriented analyses of agentic and dysregulated responses indicated distinct clusters of children linked with meaningful individual differences in marital and psychosocial functioning. Results are discussed in terms of possible mechanisms of child effects, such as increased parental awareness of children's distress potentially leading to reduced marital conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Specifying and animating facial signals for discourse in embodied conversational agents

People highlight the intended interpretation of their utterances within a larger discourse by a diverse set of non‐verbal signals. These signals represent a key challenge for animated conversational agents because they are pervasive, variable, and need to be coordinated judiciously in an effective contribution to conversation. In this paper, we describe a freely available cross‐platform real‐time facial animation system, RUTH , that animates such high‐level signals in synchrony with speech and lip movements. RUTH adopts an open, layered architecture in which fine‐grained features of the animation can be derived by rule from inferred linguistic structure, allowing us to use RUTH , in conjunction with annotation of observed discourse, to investigate the meaningful high‐level elements of conversational facial movement for American English speakers. Copyright © 2004 John Wiley & Sons, Ltd.