Rule-plus-exception model of classification learning.

Proposes a rule-plus-exception model (RULEX) of classification learning. According to RULEX, people learn to classify objects by forming simple logical rules and remembering occasional exceptions to those rules. Because the learning process in RULEX is stochastic, the model predicts that individual Ss will vary greatly in the particular rules that are formed and the exceptions that are stored. Averaged classification data are presumed to represent mixtures of these highly idiosyncratic rules and exceptions. RULEX accounts for numerous fundamental classification phenomena, including prototype and specific exemplar effects, sensitivity to correlational information, difficulty of learning linearly separable vs nonlinearly separable categories, selective attention effects, and difficulty of learning concepts with rules of differing complexity. RULEX also predicts distributions of generalization patterns observed at the individual S level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Probability learning with four event classes of schematic stimuli.

Describes 2 experiments with a total of 80 college students in which classification performance was explored using distorted patterns within a sequentially dependent temporal context. Visual stimuli representing 4 prototype classes were used. All Ss classified patterns by identifying each with 1 of 4 prototypes, and rated the similarity of each pattern to the prototypes. In addition, Ss in 2 groups predicted which pattern would occur next and indicated their confidence in that prediction. Stimulus classes were arranged so that there were sequential dependencies to be learned. Results indicate that both classification and prediction performance improved with sequence redundancy. Prediction performance improved during training, demonstrating that probability learning can occur even when the S is dealing with distorted patterns. Moreover, sequential dependencies in the stimulus sequence facilitated Ss' accurate classification of the patterns. (French summary) (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Between ignorance and truth: Partition dependence and learning in judgment under uncertainty.

In 3 studies, participants viewed sequences of multiattribute objects (e.g., colored shapes) appearing with varying frequencies and judged the likelihood of the attributes of those objects. Judged probabilities reflected a compromise between (a) the frequency with which each attribute appeared and (b) the ignorance prior probability cued by the number of distinct values that the focal attribute could take on. Thus, judged probabilities were partition dependent, varying with the number of events into which the state space was subjectively divided. This bias was diminished among participants more confident in what they learned, was strong and insensitive to level of confidence when ignorance priors were especially salient, and required ignorance priors to be salient only when probabilities were elicited (not during encoding). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sequential effects in judgment.

The absolute judgment of a stimulus is often affected by the particular order of presentation of the preceding stimuli. The scale of judgment is anchored by the 2 extreme stimuli, dampening these sequential effects except when the range is extended or when conditions favor shifts in the remembered values of the extreme stimuli. An experimental situation was developed to create the latter conditions. Successive identifications were required for long, randomized sequences of the same 2 stimuli. The sequential effects obtained in this situation were used to evaluate alternative adaptation-level (AL) models, involving the simplest interpretations of the theory and also special assumptions about anchoring by extreme stimuli. This work illustrates a direction for further development of the AL theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Probability learning on incidentally observed dimensions: A response bias effect.

Performed 2 experiments with 140 university students which demonstrate the occurrence of response bias effects as a function of previous probability learning and which are independent of stimulus dimensions. In Exp I, Ss first received training predicting the alternatives on a brightness dimension of metric patterns on a 70-30 probability distribution with the incidental dimensions of symmetry and concentration varying independently either on 70-30 or 50-50 distributions. After 200 trials, Ss were shifted to an incidental dimension; they predicted dimension alternatives on the incidental dimensions at a rate higher than appropriate controls Ss with no prior training. Exp II demonstrated that the response bias effect was dependent on the nature of the prior probability training. Ss first predicted on a 70-30 distribution of shape and were shifted to either a 70-30 or 50-50 distribution of nonsense syllables. Comparisons with nontraining control groups showed that Ss with prior training predicted the nonsense syllable alternatives at a higher rate. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual learning and free classification

Two experiments are reported that investigate the effects of stimulus preexposure on discrimination performance in a free classification task, using adult humans as subjects. In free classification subjects are asked to put stimuli into groups in any way that seems reasonable or sensible to them. Experiment 1 shows that the effect of preexposure is contingent on stimulus structure. Experiment 1b is the first demonstration of a retardation in learning as a consequence of simple preexposure in adult human subjects (previous demonstrations have relied on incidental or masked preexposure). Experiment 2 further supports the conclusions of Experiment 1 and extends them with the demonstration that stimulus similarity is a crucial factor. Taken together, these experiments rule out a class of attention-based explanations of the phenomena reported here. The experiments also provide novel information about the effects of preexposure. Preexposure can change the actual classifications subjects form in addition to altering the rate at which they are formed. Implications of these results for current theories of category formation and perceptual learning are considered.     

Comparison of professional judgment versus an algorithm for nutrition status classification

OBJECTIVES: The classification of a patient's nutrition status is important for identifying patients who require nutrition care, for designing effective nutrition interventions, and for measuring severity of illness. The objective of this study was to evaluate the reliability and validity of two variants of the Department of Veterans Affairs' nutrition status classification: professional judgment versus an algorithm. METHODS: The study consisted of two phases, both of which included providing a sample of approximately 60 registered dietitians and 60 clinical dietetic technicians with data on 16 (phase I) and 20 (phase II) patients, to which they assigned nutrition statuses using both professional judgment and the algorithm. Improvements in instructions and training were implemented between the two phases. Interrater reliability of the responses was calculated, and content validity was measured by comparing the staff's responses with those of an expert panel. RESULTS: Reliability improved significantly between phases for both professional judgment and the algorithm. Greater reliability and validity were observed with use of the algorithm, by both dietitians and technicians, during both phases. CONCLUSION: Classification of a patient's nutrition status is important in the delivery of cost-effective health care. The Department of Veterans Affairs' nutrition status classification is a good one for assessing nutrition status quickly and reliably, especially when an algorithm is used. The results underscore the advantages of a classification system based on an algorithm when the system is designed to be used by many different staff across multiple facilities.     

On the role of causal intervention in multiple-cue judgment: Positive and negative effects on learning.

Previous studies have suggested better learning when people actively intervene rather than when they passively observe the stimuli in a judgment task. In 4 experiments, the authors investigated the hypothesis that this improvement is associated with a shift from exemplar memory to cue abstraction. In a multiple-cue judgment task with continuous cues, the data replicated the improvement with intervention and participants who experimented more actively produced more accurate judgments. In a multiple-cue judgment task with binary cues, intervention produced poorer accuracy and participants who experimented more actively produced poorer judgments. These results provide no support for a representational shift but suggest that the improvement with active intervention may be limited to certain tasks and environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Clinical judgment in geropsychology practice.

418 clinical psychologists (aged 28–77 yrs) were mailed a clinical judgment survey containing a standard case history that varied according to age (46 or 72 yrs), class (working or middle), and gender of client. Clients were rated along Likert scales on dependent variables tapping attitudinal (e.g., "usefulness of intervention"), symptomatological (e.g, "disorientation"), and diagnostic dimensions. MANOVA analyses demonstrated that the 72-yr-old client elicited significantly more negative perceptions, including more "psychotic" diagnoses than the 46-yr-old client. Results provide evidence for ageism in the psychotherapy setting and treatment. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generation effects in frequency judgment.

The generation effect is the advantage in memory for information that is self-produced, rather than read. Seven experiments studied this effect on tasks requiring memory for frequency of occurrence. Generation effects were found on both relative and absolute frequency judgment and for both rhyming and letter-switching generation tasks. No generation effect was found on items at the lowest true frequency, when repetitions were massed, when nonwords were used as stimuli, or when subjects were given accurate frequency information during list presentation. These results are discussed in terms of a multiple-trace account of frequency information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development in moral judgment research.

Two recent articles challenge cognitive developmental interpretations given to moral judgment research using preference data. One article, by J. J. Moran et al (see record 1979-28407-001), suggests that preference data may reflect preference for language sophistication rather than for levels of moral reasoning. The other article, by R. M. Martin (see record 1978-11439-001), suggests that preference for statements of moral reasoning may reflect a prior commitment to an action choice rather than an evaluation of moral reasoning. The evidence in both articles is critiqued, subsequent research dealing with the problems raised is cited, and a reconceptualization of the issues is recommended. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit stereotyping in person judgment.

Three experiments demonstrated implicit gender stereotyping. A target's social category determined the use of previously primed stereotyped information, without Ss' awareness of such influence. After unscrambling sentences describing neutral or stereotyped behaviors about dependence or aggression, Ss evaluated a female or male target. Although ratings of female and male targets did not differ after exposure to neutral primes, Ss exposed to dependence primes rated a female target as more dependent than a male target who performed identical behaviors (Exp 1A). Likewise, Ss rated a male, but not a female, target as more aggressive after exposure to aggression primes compared with neutral primes (Exp 1B). Exp 2 replicated the implicit stereotyping effect and additionally showed no relationship between explicit memory for primes and judgment of target's dependence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Techniques for the study of learning in animals: Analysis and classification.

Present classifications of techniques for the study of animal learning are inadequate. The proposed classification is developed in terms of the functional significance of differences in technique. Thus 2 techniques differ if they yield results which differ in some fundamental respect but may be considered interchangeable if they produce similar results. The 3 major classifications are: Thorndikian Situations, Pavlovian Situations, and Avoidance Situations. Each major classification is subdivided to account for techniques appropriate to the specific situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of generic advance instructions on learning a classification task.

Investigated whether giving students generic advance instructions about how to learn a classification task would be effective in facilitating learning of a specific classification task. The effect of instructions was compared with the effects of adjunct postquestions, simply reading the materials (control group), and both instructions and adjunct postquestions. The experimental task involved learning to classify instances of several different categories. Ss were 72 US Navy enlisted personnel. It was hypothesized that advance instructions to Ss regarding how and what to learn would facilitate learning of classification material. Results show that the instruction group and adjunct questions group did equally well on classifying new and old instances of US Navy call signs. All groups did better than control groups. Results suggest that students can learn a general strategy for processing classification material and that providing students with generic information about how and what to learn is an effective instructional strategy. A text of the instructions used to teach Ss how to learn a classification task is appended. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On consciousness in syntactic learning and judgment: A reply to Reber, Allen, and Regan.

Responds to comments by A. S. Reber et al (see record 1986-03030-001) on the present authors' (see record 1985-29949-001) analysis of consciousness and abstraction in the case of syntactical learning and judgment. The methodological criticism of Reber et al is rejected, and it is asserted that assessment at the moment of judgment rather than recall maximizes the validity of reports of rules in consciousness at many moments of judgment. Broader issues discussed include judgment after early learning and after automatization, correlated grammars and consciousness, the scope and mental abstractness of rules, conscious and unconscious control, and intuition. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The development of a general associative learning account of skill acquisition in a relative arrival-time judgment task.

Current theory assumes that individuals only use information from the immediate environment to perform relative arrival-time judgment tasks. This article presents a theoretical analysis of the memory requirements of this task. The authors present an analysis of the inputs to the memory system and the processes that map those inputs onto outputs. The analysis generates a set of predictions regarding the specificity of transfer and the role of context during learning. In 3 experiments, participants decided whether pairs of aircraft would violate a minimum separation standard or pass each other safely. Participants were presented with pairs of aircraft in which properties of the pair varied along 3 structural and 3 surface dimensions. Contexts were defined by the co-occurrence of specific values along stimulus dimensions and the use of a neutral label. The results suggest that transfer was limited by the dimensions that were varied in training and the context in which those dimensions were varied. The discussion focuses on the problems that complex tasks like relative judgment pose for associative learning mechanisms and the development of precise models of cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Quality of group judgment.

Examined the quality of group judgment in situations in which groups have to express an opinion in quantitative form. To provide a measure for evaluating the quality of group performance (which is defined as the absolute value of the discrepancy between the judgment and the true value), 4 baseline models are considered. These models provide a standard for evaluating how well groups perform. The 4 models are: (a) randomly picking a single individual; (b) weighting the judgments of the individual group members equally (the group mean); (c) weighting the 'best' group member (i.e., the one closest to the true value) totally where the best is known, a priori , with certainty; (d) weighting the best member totally where there is a given probability of misidentifying the best and getting the 2nd, 3rd, etc, best member. These 4 models are examined under varying conditions of group size and "bias." Bias is defined as the degree to which the expectation of the population of individual judgments does not equal the true value (i.e., there is systematic bias in individual judgments). A method is then developed to evaluate the accuracy of group judgment in terms of the 4 models. The method uses a Bayesian approach by estimating the probability that the accuracy of actual group judgment could have come from distributions generated by the 4 models. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conflict and moral judgment.

Employed a conflict procedure, in which reliance on adult values was opposed to reliance on damage as a measure of blame, in a study with 20 preschool children, 50 2nd graders, and 25 adults. The procedure facilitated the 2nd graders' use of intention in making moral judgments of story pairs, but conflict had no effect on the judgments of preschoolers or adults. Question wording affected adults but not 2nd graders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Accentuation and perspective in attitudinal judgment.

Studied 185 15–16 yr old high school students' and 73 undergraduates' judgments of statements concerning the nonmedical use of drugs as affected by judges' attitudes toward the issue, the range of items presented, and value connotations. As predicted by accentuation theory, prodrug judges gave more polarized ratings on scales where the "pro" end was more positively labeled (P+), and antidrug Ss gave more polarized ratings on scales where the "anti" end was the more positive (A+); this replicated previous findings. Also, as predicted, more polarized ratings were given on P+ than on A+ scales when the item range was aborted at the pro end and vice versa when it was aborted at the anti end. It is argued that judgment does not necessarily depend on the total subjective range of items that a judge takes into account (the original definition of perspective) but rather on the perceived appropriateness of a given scale to a given region of the underlying continuum. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)