Rectangles may appear to reverse like trapezia when they rotate at an uneven rate.

A 1983-1985 theory by Mitchell and Power predicts that, when rotating rectangles undergo certain kinds of speed fluctuation, they should appear to reverse just as trapezia do. The prediction is partially confirmed. One of two 'mimic' rectangles underwent apparent reversals more often than a control rectangle undergoing even rotation and in the same places as rotating trapezia. However, its reversal frequency was less than those of the trapezia, and a second 'mimic' slowed an inappropriate distribution of reversals round the cycle. These anomalies call for some modification to Mitchell and Power's theory, but minor qualifications may be sufficient.     

Apparent reversal frequencies in squares and trapezia: the effect of invariant and variant information

Three studies of apparent reversals (ARs) in rotating rectangular and trapezoid arrays are reported, together with a mathematical analysis. Study 1 explores the effect of different degrees of outline suppression on the frequency and distribution of ARs in squares and trapezia. Study 2 examines how modifications in both types of array reduce AR frequency, demonstrates a manipulation whereby ARs in rotating squares are eliminated, and suggests that ARs in squares and trapezia are of different origins. In the mathematical analysis, an invariant characteristic of the transformations of rotating rectangles is reported, and from this a numerical index is developed that expresses the extent to which a rotating trapezium may appear to pause just before each point of oscillation. In study 3 it is shown that this measure is a better predictor of AR frequencies than the heuristic proposed by Braunstein.     

Assessing the empirical validity of the "take-the-best" heuristic as a model of human probabilistic inference

The boundedly rational 'Take-The-Best" heuristic (TTB) was proposed by G. Gigerenzer, U. Hoffrage, and H. Kleinb?lting (1991) as a model of fast and frugal probabilistic inferences. Although the simple lexicographic rule proved to be successful in computer simulations, direct empirical demonstrations of its adequacy as a psychological model are lacking because of several methodical problems. In 4 experiments with a total of 210 participants, this question was addressed. Whereas Experiment 1 showed that TTB is not valid as a universal hypothesis about probabilistic inferences, up to 28% of participants in Experiment 2 and 53% of participants in Experiment 3 were classified as TTB users. Experiment 4 revealed that investment costs for information seem to be a relevant factor leading participants to switch to a noncompensatory TTB strategy. The observed individual differences in strategy use imply the recommendation of an idiographic approach to decision-making research.     

Observer age and the social transmission of attractiveness in humans: Younger women are more influenced by the choices of popular others than older women

Being paired with an attractive partner increases perceptual judgements of attractiveness in humans. We tested experimentally for prestige bias, whereby individuals follow the choices of prestigious others. Women rated the attractiveness of photographs of target males which were paired with either popular or less popular model female partners. We found that pairing a photo of a man with a woman presented as his partner positively influenced the attractiveness of the man when the woman was presented as more popular (Experiment 1). Further, this effect was stronger in younger participants compared to older participants (Experiment 1). Reversing the target and model such that women were asked to rate women paired with popular and less popular men revealed no effect of model popularity and this effect was unrelated to participant age (Experiment 2). An additional experiment confirmed that participant age and not stimulus age primarily influenced the tendency to follow others' preferences in Experiment 1 (Experiment 3). We also confirmed that our manipulations of popularity lead to variation in rated prestige (Experiment 4). These results suggest a sophisticated model‐based bias in social learning whereby individuals are most influenced by the choices of those who have high popularity/prestige. Furthermore, older individuals moderate their use of such social information and so this form of social learning appears strongest in younger women.     

Mood-induced self-focused attention.

The influence of mood on self-focused attention was explored in 2 experiments involving the induction of moods in the laboratory. Experiment 1 tested the hypothesis that mood states, whether pleasant or unpleasant, induce self-focused attention. This hypothesis was supported using a sentence completion task as the measure of self-focus. Experiment 2 replicated Experiment 1 results using a measure of self-complexity as an index of self-focus. These experiments provide support for a model of affect-action sequences the first step of which entails the turning of attention toward the self in response to the arousal of affect.     

Visually-presented letter strings typically are encoded phonologically: some converging evidence

Three experiments were conducted to show that phonological encoding is typical for visually-presented letter strings, and that an interactive activation model with a phonological route to the mental lexicon accounts adequately for the word-superiority effect. In Experiment 1, pseudohomophones produced a word-superiority effect that was as great as that produced by words. More accurate target discrimination in homophones than in nonhomophones in Experiment 2 was interpreted to mean that excitability of entries in the mental lexicon increases with frequency of access. Target discrimination accuracy was inversely related to the phonological complexity of strings containing targets in Experiment 3, supposedly because lexical access through which target discrimination is enhanced becomes more difficult as phonological complexity increases.     

Category representation for classification and feature inference

This research's purpose was to contrast the representations resulting from learning of the same categories by either classifying instances or inferring instance features. Prior inference learning research, particularly T. Yamauchi and A. B. Markman (1998), has suggested that feature inference learning fosters prototype representation, whereas classification learning encourages exemplar representation. Experiment 1 supported this hypothesis. Averaged and individual participant data from transfer after inference training were better fit by a prototype than by an exemplar model. However, Experiment 2, with contrasting inference learning conditions, indicated that the prototype model was mimicking a set of label-based bidirectional rules, as determined by the inference learning task demands in Experiment 1. Only the set of rules model accounted for all the inference learning conditions in these experiments.     

Development of syntax in a retarded girl using procedures of imitation, reinforcement, and modelling

Three experiments demonstrated the development and generalized use of a singular and plural declarative sentence in a child initially lacking sentence form responses. In each experiment, an adult(s) served as a language model(s), and consequences (sweets) were provided for imitation of the model. During training trials, an item(s) was displayed first to the model(s) then to the subject; these displays were accompanied by requests to label the item(s). Generalization was assessed by a number of probe trials that were periodically interspersed among training trials. During these trials, the subject was requested to label the displayed item(s) without any preceding labelling response from the model. Using these procedures, generalized use of a singular sentence ("That is one-") resulted in Experiment I, and generalized use of a plural sentence ("These are two-") resulted in Experiment II. In Experiment III, two models (a singular and a plural sentence model) were made available to the subject but imitation of only one model was reinforced during any one condition. Results indicated the subject labelled probe (generalization) items with the same sentence form that was modelled and reinforced during training trials.     

A Multinomial Model to Assess Fluency and Recollection in a Sequence Learning Task

We suggest that well-formedness judgements in conjunction with L.L. Jacoby's (1991) process dissociation procedure and an appropriate measurement model can be used to obtain measures of implicit and explicit sequence knowledge. We introduce a new measurement model designed specifically for the sequence learning task. The model assumes that sequence identification is based on recollection, perceptual or motor fluency, systematicity detection, and guessing. The model and the application of the process dissociation procedure were empirically evaluatedusing auditory eventsequences. In Experiment 1, the parameterreflecting recollection was higher in an intentional than in an incidental learning condition. Experiment 2 showed that random sequences interspersed among the systematic sequences during the acquisition phase may change this pattern of results. A manipulation of processing fluency in Experiment 3 was reflected in the appropriate model parameter. In sum, the new measurement model and the application of the process dissociation procedure appear to be useful tools in sequence learning research.     

Sources of sentence constraint on lexical ambiguity resolution

Results from a series of naming experiments demonstrated that major lexical categories of simple sentences can provide sources of constraint on the interpretation of ambiguous words (homonyms). Manipulation of verb (Experiment 1) or subject noun (Experiment 2) specificity produced contexts that were empirically rated as being strongly biased or ambiguous. Priming was demonstrated for target words related to both senses of a homonym following ambiguous sentences, but only contextually appropriate target words were primed following strongly biased dominant or subordinate sentences. Experiment 3 showed an increase in the magnitude of priming when multiple constraints on activation converged. Experiments 4 and 5 eliminated combinatorial intralexical priming as an alternative explanation. Instead, it was demonstrated that each constraint was influential only insofar as it contributed to the overall semantic representation of the sentence. When the multiple sources of constraint were retained but the sentence-level representation was changed (Experiment 4) or eliminated (Experiment 5), the results of Experiments 1, 2, and 3 and were not replicated. Experiment 6 examined the issue of homonym exposure duration by using an 80-msec stimulus onset asynchrony. The results replicated the previous experiments. The overall evidence indicates that a sentence context can be made strongly and immediately constraining by the inclusion of specific fillers for salient lexical categories. The results are discussed within a constraint-based, context-sensitive model of lexical ambiguity resolution.     

Source reliability and the conjunction fallacy

Information generally comes from less than fully reliable sources. Rationality, it seems, requires that one take source reliability into account when reasoning on the basis of such information. Recently, Bovens and Hartmann (2003) proposed an account of the conjunction fallacy based on this idea. They show that, when statements in conjunction fallacy scenarios are perceived as coming from such sources, probability theory prescribes that the "fallacy" be committed in certain situations. Here, the empirical validity of their model was assessed. The model predicts that statements added to standard conjunction problems will change the incidence of the fallacy. It also predicts that statements from reliable sources should yield an increase in fallacy rates (relative to unreliable sources). Neither the former (Experiment 1) nor the latter prediction (Experiment 3) was confirmed, although Experiment 2 showed that people can derive source reliability estimates from the likelihood of statements in a manner consistent with the tested model. In line with the experimental results, model fits and sensitivity analyses also provided very little evidence in favor of the model. This suggests that Bovens and Hartmann's present model fails to explain fully people's judgements in standard conjunction fallacy tasks.     

Power, individuation, and the cross-race recognition deficit

The well-known cross-race effect (CRE) in facial recognition is observed as better recognition for faces of one’s own race than faces of another race. Across two experiments, this very robust phenomenon was attenuated via an increase in cross-race (CR) recognition when CR targets were perceived as wielding power either because of their occupational roles (Experiment 1) or the behaviors in which they engaged (Experiment 2). Furthermore, evidence in Experiment 2 indicates that neither target stereotypicality nor target valence can easily explain the observed increase in CR recognition. These results conform closely to predictions derived from a social-cognitive model of the cross-race effect.     

The Motivated Expression of Embarrassment Following a Self-Presentational Predicament

ABSTRACT Two experiments tested hypotheses derived from an interpersonal model of embarrassment. According to this model, people who have suffered a self-presentational predicament are motivated to convey to others that they feel embarrassed as a way of repairing their social image and lowering subjective embarrassment in such situations. In Experiment 1, participants who performed an embarrassing task subsequently expressed greater embarrassment if the researcher did not already know that they were embarrassed than if she was aware of their embarrassment. Experiment 2 showed that embarrassed participants who thought that the researcher did not interpret their blushing as a sign of embarrassment subsequently engaged in alternative self-presentational tactics to improve their damaged social image.     

Comprehension of the Referential Intent of Looking and Pointing Between 12 and 15 Months

Butler, Caron, & Brooks (2000) tested the gaze following of 14-and 18-month-olds under 3 conditions: (1) when the adult's view of the targets was blocked by barriers, (2) when the barriers contained open windows, and (3) no barriers. Contrary to a nonmentalist "ecological" model (adult turns serve as cues to the location of interesting events), frequency of gaze following by 14-month-olds was not equivalent across the 3 conditions. Contrary to a mentalist model (infant wants to see what the adult is seeing), gaze following was not substantially less in the barrier than in the window and no-barrier conditions (as was the case for 18-month-olds). To examine whether the barriers posed vector projection problems for essentially nonmentalist, or line-of-sight problems for essentially mentalist younger infants, 3 experiments were conducted. In Experiment 1, a 12-month group was tested in the same 3 conditions to determine if, being younger, they might yield a more clearcut nonmentalist pattern. Contrarily, they behaved like Butler et al.'s 14-month-olds. In Experiment 2, a 14-month group was tested in the barrier and window conditions, but now combining pointing with turning. Infants behaved as predicted by the mentalist model: strong responding in the window condition and minimal in the barrier (where many strained to look inside the partitions). In Experiment 3, an attempt was made to differentiate between mentalist and "geometric" (vector projection) interpretations of the results of Experiment 2 by testing another 14-month group with the adult's eyes closed while pointing. Gaze following now dropped precipitously in the window condition as did looking inside the solid barriers, indicating (1) that infants in Experiment 2 had not simply been guided to target by an extended arm, but construed it as part of a referential act that was as much visual as gestural, and (2) that by 14 months, infants may have acquired a mentalistic concept of seeing.     

Effects of an auditory model on the learning of relative and absolute timing

The effects of an auditory model on the learning of relative and absolute timing were examined. In 2 experiments, participants attempted to learn to produce a 1,000- or 1,600-ms sequence of 5 key presses with a specific relative-timing pattern. In each experiment, participants were, or were not, provided an auditory model that consisted of a series of tones that were temporally spaced according to the criterion relative-timing pattern. In Experiment 1, participants (n = 14) given the auditory template exhibited better relative- and absolute-timing performance than participants (n = 14) not given the auditory template. In Experiment 2, auditory and no-auditory template groups again were tested, but in that experiment each physical practice participant (n = 16) was paired during acquisition with an observer (n = 16). The observer was privy to all instructions as well as auditory and visual information that was provided the physical practice participant. The results replicated the results of Experiment 1: Relative-timing information was enhanced by the auditory template for both the physical and observation practice participants. Absolute timing was improved only when the auditory model was coupled with physical practice. Consistent with the proposal of D. M. Scully and K. M. Newell (1985), modeled timing information in physical and observational practice benefited the learning of the relative-timing features of the task, but physical practice was required to enhance absolute timing.     

Causal Induction in the Presence of a Perfect Negative Cue: Contrasting Predictions from Associative and Statistical Models

Two experiments on human causal induction with multiple candidate causes are reported. Experiment 1 investigated the influence of a perfect preventive cause on the ratings of a less contingent cause. Whereas the Rescorla-Wagner model (RWM) and Cheng's probabilistic contrast model predict that the less contingent cause should be completely discounted, the Pearce model predicts, in most cases, an enhancement of that cause's perceived importance. Results corresponded more closely tothe predictions of the Pearce model.The predictions of both the RWM and the Pearce model rely on a constant context cue acquiring associative strength, yet no such cue was explicitly identified in the task scenario employed in Experiment 1. Experiment 2 replicated a number of key conditions of Experiment 1 with a task scenario that afforded ratings of the causal importance of the context in which the effectiveness of the discrete candidate causes was evaluated. In addition, the number of trials was increased to test the possibility that the ratings in Experiment 1 were the product of incomplete learning. The results of the first experiment were replicated and the ratings of the effectiveness of the context cue were anticipated by both the RWM and the Pearce model. Overall, the Pearce model offers a more comprehensive account of the causal inferences recorded in this study.     

A diffusion model analysis of adult age differences in episodic and semantic long-term memory retrieval

Two experiments investigated adult age differences in episodic and semantic long-term memory tasks, as a test of the hypothesis of specific age-related decline in context memory. Older adults were slower and exhibited lower episodic accuracy than younger adults. Fits of the diffusion model (R. Ratcliff, 1978) revealed age-related increases in non-decisional reaction time for both episodic and semantic retrieval. In Experiment 2, an age difference in boundary separation also indicated an age-related increase in conservative criterion setting. For episodic old-new recognition (Experiment 1) and source memory (Experiment 2), there was an age-related decrease in the quality of decision-driving information (drift rate). As predicted by the context-memory deficit hypothesis, there was no corresponding age-related decline in semantic drift rate.     

Integration and representation in rats' serial pattern learning in the T-maze

Rats were exposed to three-trial series consisting of reinforced (R) trials and one nonreinforced (N) trial in a fixed order, RRN and RNR (Experiments 1 and 2) or NRR and RRN (Experiment 3), on extended visually distinct runways in a T-maze. When initially presented with the same sequence on each series in a session (separate presentations) with the same runway on all trials within a series (Experiments 1 and 3), all the rats developed slower running speeds on N than on R trials. When a runway was sometimes changed between the first and next two trials during separate presentations training (Experiment 2) or both sequences were later intermixed within each session in each experiment, only rats exposed to each sequence on a specific runway maintained these serial running patterns. Rats displayed serial running patterns on a test RNN sequence similar to that on the RNR sequence (Experiment 2), as would be predicted by an intertrial association model of serial pattern learning (Capaldi & Molina, 1979), but responded on test RRR and NRN sequences (Experiment 3) as would be predicted by an ordinal-trial-tag/intratrial association model (Burns, Wiley, & Payne, 1986). Results from test series of free-choice trials in Experiments 1 and 2 failed to support a prediction of the intratrial association model that these rats would integrate RRN and RNR sequences. Rather than always selecting a baited runway on both the second and the third free-choice trials, the rats only selected a baited runway on the third trial on the basis of their choice on the second trial, as would be predicted by the intertrial association model. Only after experiencing all possible outcome sequences during forced-choice training in Experiment 3 did these rats predominantly select a baited runway on every free-choice trial.     

Previewing the neighborhood: the role of orthographic neighbors as parafoveal previews in reading

In 2 experiments, a boundary technique was used with parafoveal previews that were identical to a target (e.g., sleet), a word orthographic neighbor (sweet), or an orthographically matched nonword (speet). In Experiment 1, low-frequency words in orthographic pairs were targets, and high-frequency words were previews. In Experiment 2, the roles were reversed. In Experiment 1, neighbor words provided as much preview benefit as identical words and greater benefit than nonwords, whereas in Experiment 2, neighbor words provided no greater preview benefit than nonwords. These results indicate that the frequency of a preview influences the extraction of letter information without setting up appreciable competition between previews and targets. This is consistent with a model of word recognition in which early stages largely depend on excitation of letter information, and competition between lexical candidates becomes important only in later stages.