An evidential support accumulation model of subjective probability

A model of cue-based probability judgment is developed within the framework of support theory. Cue diagnosticity is evaluated from experience as represented by error-free frequency counts. When presented with a pattern of cues, the diagnostic implications of each cue are assessed independently and then summed to arrive at an assessment of the support for a hypothesis, with greater weight placed on present than on absent cues. The model can also accommodate adjustment of support in light of the baserate or prior probability of a hypothesis. Support for alternatives packed together in a "residual" hypothesis is discounted; fewer cues are consulted in assessing support for alternatives as support for the focal hypothesis increases. Results of fitting this and several alternative models to data from four new multiple-cue probability learning experiments are reported.     

Rigidity in children's drawings and its relation with representational change

Four studies tested the application of to the drawing domain. In particular, we tested her claim that young children are inhibited in their attempts at changing their graphic representations (representational change) due to being constrained by the order in which the elements of the representation are drawn (procedural rigidity). The first study required 60 children (4- to 6-year-olds and an older comparison group of 8-year-olds) to make three drawings of a familiar and novel topic. From these drawings each child was measured for procedural rigidity. In a further drawing the child was asked to modify their usual representation of each topic. Regression analyses revealed procedural rigidity levels were not predictive of manipulation performance. A second study, testing 75 4- to 6-year-olds and a third study, testing 30 3- to 4-year-olds, revealed that when young children were specifically asked to manipulate rigid sub-procedures on a familiar topic they were indeed able to do so. Finally, a fourth study (testing 40 5-year-olds and 40 8-year-olds) removed the notational trace in drawing (a possible aid for procedural interruption) but this still produced no evidence of a relation between procedural rigidity and representational change. We suggest how the concept of procedural rigidity might be re-interpreted for the drawing domain so that the RR model can remain as a domain-general theory of cognitive development. We also suggest the development of information processing may be crucial for flexibility in drawing.     

Locomotion,incidental learning,and the selection

In three experiments, we examined the effects of locomotion and incidental learning on the formation of spatial memories. Participants learned the locations of objects in a room and then made judgments of relative direction, using their memories (e.g., "Imagine you are standing at the clock, facing the jar. Point to the book"). The experiments manipulated the number of headings experienced, the amount of interaction with the objects, and whether the participants were informed that their memories of the layout would be tested. When participants were required to maintain a constant body orientation during learning (Experiment 1), they represented the layout in terms of a single reference direction parallel to that orientation. When they were allowed to move freely in the room (Experiment 2), they seemed to use two orthogonal reference axes aligned with the walls of the enclosing room. Extensive movement under incidental learning conditions (Experiment 3) yielded a mixture of these two encoding strategies across participants. There was no evidence that locomotion, interaction with objects, or incidental learning led to the formation of spatial memories that differed from those formed from static viewing.     

Perceptual judgements of others' tasting experiences: are they enjoying their food?

Motivated by previous work suggesting that infants make stereotypic facial reactions to different tastes, we assessed communicative signals that might enable an adult to interpret the strength, taste, and hedonic value of a liquid flavour another adult is consuming. Four subjects (tasters) were overtly videoed consuming drinks that varied in strength (low, medium, and high concentrations), taste (sweet, sour, bitter, and salty), and hedonic value (taster-rated enjoyment). 26 observers assessed the strength, taste, and taster's enjoyment of the drink from video clips of the tasters. Observers perceived the hedonic value of the drinks to the taster and the drinks' strength based on the tasters' reactions but were generally poor at assessing the specific taste of the drink. For all tastes except the bitter ones, observers might have based their judgements of taste on how much the taster appeared to enjoy the drink. These findings are discussed in terms of communication of food's value.     

Emotional competence and aggressive behavior in school-age children

Examined emotional competence in 87 children, aged 7–10 years, who varied with respect to reports of aggressive behavior to determine whether individual differences in emotional competence characterize children with higher levels of aggressive behavior. Emotional competence was assessed during a 1-hr lab visit that included (a) an observational period consisting of a modified disappointment paradigm, (b) assessment of cognitive and language abilities, and (c) 2 structured emotion interviews. Children with higher levels of aggressive behavior exhibited more intense and frequent expressions of anger, both as reported by mothers and as observed during the disappointment paradigm. Less sophisticated ability to identify the causes of emotion also characterized children with higher levels of aggressive behavior. Gender moderated the relation between aggressive behavior and type of emotion identified such that reports of happiness (in response to receiving a disappointing prize) were associated with lower levels of reported aggressive behavior for boys. The value of assessing children's emotional competence in the context of an emotionally arousing situation is suggested by these findings.     

"Isn't it fun to get the respect that we're going to deserve?" Narcissism, social rejection, and aggression

Across four studies, narcissists were more angry and aggressive after experiencing a social rejection than were nonnarcissists. In Study 1, narcissism was positively correlated with feelings of anger and negatively correlated with more internalized negative emotions in a self-reported, past episode of social rejection. Study 2 replicated this effect for a concurrent lab manipulation of social rejection. In Study 3, narcissists aggressed more against someone who rejected them (i.e., direct aggression). In Study 4, narcissists were also more aggressive toward an innocent third party after experiencing social rejection (i.e., displaced aggression). Narcissists were not more aggressive after social acceptance. Self-esteem plays little role in predicting aggression in response to rejection. These results suggest that the combination of narcissism and social rejection is a powerful predictor of aggressive behavior.     

Inflated and contradictory category naming deficits in Alzheimer's disease?

Although some studies have documented category-specific deficits in patients with Alzheimer's disease, others have not. One possible reason is that where control groups have been used in previous studies, they have performed at ceiling; and this may spuriously affect the incidence and type of deficit reported (especially with common statistical techniques such as z-scores). We examined this issue in 18 Alzheimer's patients and 26 elderly controls, who named two picture sets: a simple set that typically produces ceiling effects (Set 1) and one that produces a normal distribution in controls (Set 2). Sets 1 and 2 produced inconsistent and even contradictory deficits in the same patients. The results also show that ceiling effects may inflate the number of living thing deficits and hence, distort the reported ratio of living to nonliving cases.     

Making causal judgments from the proportion of confirming instances: the pCI rule

It is proposed that causal judgments about contingency information are derived from the proportion of confirmatory instances (pCI) that are evaluated as confirmatory for the causal candidate. In 6 experiments, pCI values were manipulated independently of objective contingencies assessed by the deltaP rule. Significant effects of the pCI manipulations were found in all cases, but causal judgments did not vary significantly with objective contingencies when pCI was held constant. The experiments used a variety of stimulus presentation procedures and different dependent measures. The power PC theory, a weighted version of the deltaP rule, the Rescorla-Wagner associative learning model (R. A. Rescorla & A. R Wagner, 1972), and the deltaD rule, which is the frequency-based version of the pCI rule, were unable to account for the significant effects of the pCI manipulations. These results are consistent with a general explanatory approach to causal judgment involving the evaluation of evidence and updating of beliefs with regard to causal hypotheses.     

The effects of different aperture-viewing conditions on the recognition of novel objects

The process of learning the structure of novel objects involves the selective use of information available in the distal stimulus. By allowing participants to explore the object within a limited field of view, we were able to examine more rigorously what regions of the object are actually selected in the learning process. Participants explored objects either by moving a circular aperture over a stationary novel object (the aperture-movement condition), or by moving the object behind a stationary aperture (the object-movement condition). Given the differences in how the spatial layout of object parts is revealed in the two study conditions, we expected that exploration would be more systematic in the aperture-movement condition than it would be in the object-movement condition, and would lead to better object recognition. We show evidence that in the aperture-movement condition exploration patterns were more related to the structure of the object and, as a consequence, the aperture-movement condition resulted in more accurate recognition in a later old--new discrimination test.     

The difference engine: A model of diversity in speeded cognition

A theory of diversity in speeded cognition, the difference engine, is proposed, in which information processing is represented as a series of generic computational steps. Some individuals tend to perform all of these computations relatively quickly and other individuals tend to perform them all relatively slowly, reflecting the existence of a general cognitive speed factor, but the time required for response selection and execution is assumed to be independent of cognitive speed. The difference engine correctly predicts the positively accelerated form of the relation between diversity of performance, as measured by the standard deviation for the group, and task difficulty, as indexed by the mean response time (RT) for the group. In addition, the difference engine correctly predicts approximately linear relations between the RTs of any individual and average performance for the group, with the regression lines for fast individuals having slopes less than 1.0 (and positive intercepts) and the regression lines for slow individuals having slopes greater than 1.0 (and negative intercepts). Similar predictions are made for comparisons of slow, average, and fast subgroups, regardless of whether those subgroups are formed on the basis of differences in ability, age, or health status. These predictions are consistent with evidence from studies of healthy young and older adults as well as from studies of depressed and age-matched control groups.