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PubMed2000

Reexamining the circumplex model of affect.

The circumplex model of affect has been among the most widely studied representations of affect. Despite the considerable evidence cited in support of it, methods typically used to evaluate the model have substantial limitations. In this article, the authors attempt to correct past limitations by using a covariance structure model specifically designed to assess circumplex structure. This model was fit to 47 individual correlation matrices from published data sets. Analyses revealed that model fit was typically acceptable and that opposing affective states usually demonstrated strong negative correlations with one another. However, analyses also indicated substantial variability in both model fit and correlations among opposing affective states and suggested several characteristics of studies that partially accounted for this variability. Detailed examination of the locations of affective states for 10 of the correlation matrices with relatively optimal characteristics provided mixed support for the model.

Affect↗

PubMed1988

Visual selection from multielement displays: measuring and modeling effects of exposure duration.

In a partial-report experiment, subjects reported the digits from a circular array of digits and letters terminated by a pattern mask. Individual frequency distributions of the number of correctly reported digits were analyzed as functions of number of digits (2, 4, or 6) and number of letters (0, 2, 4, 6, or 8) at nine exposure durations ranging from 10 to 200 ms. The distributions (hundreds of data points per subject) were accurately predicted by a four-parameter fixed-capacity independent race model that assumes exponentially distributed processing times, limitations in both processing capacity and storage capacity, and time-invariant selectivity. Estimated from the data, processing capacity C was 45 items/s, selectivity alpha (ratio between the amount of processing capacity devoted to a distractor and the amount devoted to a target) was 0.48, short-term storage capacity K was 3.5 items, and the longest ineffective exposure duration t0 was 18 ms.

Adult↗

PubMed1988

Relation between velocity and curvature in movement: equivalence and divergence between a power law and a minimum-jerk model.

Unconstrained hand movements typically display a decrease in hand speed around highly curved sections of a trajectory. It has been suggested that this relation between tangential velocity and radius of curvature conforms to a one-third power law. We demonstrate that a one-third power law can be explained by models taking account of trajectory costs such as a minimum-jerk model. Data were analyzed from 6 subjects performing elliptical drawing movements of varying eccentricities. Conformity to the one-third power law in the average was obtained but is shown to be artifactual. It is demonstrated that asymmetric velocity profiles may result in consistent departures from a one-third power law but that such differences may be masked by inappropriate analysis procedures. We introduce a modification to the original minimum-jerk model by replacing the assumption of a Newtonian point-mass with a visco-elastic body. Simulations with the modified model identify a basis for asymmetry of velocity profiles and thereby predict departures from a one-third law commensurate with the empirical findings.

Adult↗

PubMed1997

Visual search as a function of type of prior experience with target and distractor.

In a visual search task, participants identified the presence of a unique shape against a background of homogeneous distractors. Types of prior experience with the target, the distractor, or both were examined. In 2 experiments, a preexposure (PE) phase was followed by a test phase. The test display consisted of a target that was either target or distractor in PE or novel. Distractors were either targets or distractors in PE or novel. Reaction time was fastest for novel targets with familiar distractors, irrespective of the source of familiarity, and slowest for novel targets with novel distractors. Results are discussed in terms of attentional explanations of latent inhibition (LI) and perceptual learning and of visual search phenomena, such as novel popout. LI, previously attributed only to a deficit in the stimulus preexposed group, may also be due to enhanced performance in the nonpreexposed group.

Association↗

PubMed2000

Measurement error in subliminal perception experiments: simulation analyses of two regression methods.

A. G. Greenwald, M. R. Klinger, and E. S. Schuh (1995) investigated subliminal perception using a regression-based test for a dissociation between direct and indirect measures of perceptual ability. Direct and indirect measures were obtained for each observer, and a regression analysis was used to predict the amount of indirect perception at the point where the direct measure showed zero sensitivity. A significant positive intercept, obtained with both standard regression and a modified regression developed by K. C. Klauer, S. C. Draine, and A. G. Greenwald (1998), was used to argue for the key dissociation. When the assumptions of these methods are not met, however, simulations indicate that significant positive intercepts can often be obtained even if there is no dissociation. Moreover, the assumptions are theoretically implausible and inconsistent with some aspects of the results. Thus, the significant positive intercept is not strong evidence of the key dissociation.

Computer Simulation↗

PubMed1979

Selective inattention to anxiety-linked stimuli.

The term selective inattention as used here subsumes those phenomena whose primary function is the active blocking or attenuation of partially processed contents en route to conscious expression. Examples are anxiety-motivated forgetting or perceptual distortion and hypnotically induced negative hallucinations. Studies in the field of selective attention have typically been designed to explain what takes place in a task in which the subject is first instructed to attend to a particular stimulus and then to consciously execute that instruction as well as he can. The rejection of content in process is examined only sceondarily as a consequence of the acceptance of relevant information. In the present experiments and theorizing, the emphasis instead is on inhibitory operations that take place automatically, without conscious intent, in response to a potential anxiety reaction. Experiment 1 explored the interaction of anxiety-linked inattention with strength of a target stimulus. Three female subjects were programmed under hypnosis to respond posthypnotically in the On condition with prescribed degrees of anxiety when certain Blacky pictures popped into mind later ,t the end of experimental trials; in the Off conditionall pictures were to become neutral. With the three female subjects still under hypnosis, each of the loaded pictures was then paired with a four-letter work relevant to the individual's own version of what was happening in the picture. The waking recognition task, carried out with amnesia for the prior hypnotic programming, consisted of tachistoscopic exposure of loaded words and physically similar filler words at four durations within a baseline range of recognition accuracy from 50%--75% correct. The data yielded a curvilinear relationship in which the recognition of only the loaded words was significnatly lower in the On condition at the 60%--70% range of recognition accuracy but not at shorter or longer stimulus durations. Experiment 2, for which the prior hypnotic programming of the same three subjects was similar to Experiment 1, used an anagram approach to comparable four-letter words, except that pleasure-loaded words were introduced as a control along with filler words. Four durations of tachistoscopic exposure of the anagrams were used with each individual, and the major dependent variable was response latency measured in milliseconds. An independent measure of perceptual discriminability of the scrambled stimulus letters was obtained to isolate perceptual from cognitive aspects of the task. The results indicated that both low perceivability and high solvability increase the likelihood of response delays specifically in the presence of anxiety-linked stimuli. Experiment 3 was a nonhypnotic replication of Experiment 2, using 12 male and 13 female subjects. The potential affective loading of key anxiety and pleasure words was accomplished by structured scenarios for the Blacky pictures in which subjects were asked to place themselves as vividly as possible...

Adult↗

PubMed1992

Similarity, identification, and categorization: comment on Ashby and Lee (1991)

Ashby and Lee (1991) tested various models derived from the general recognition theory (GRT; Ashby & Perrin, 1988; Ashby & Townsend, 1986) on their ability to predict and interrelate similarity, categorization, and identification performance. This commentary (a) argues that contrary to Ashby and Lee's suggestion, the likelihood-based GRT cannot generally predict categorization from identification without incorporating selective attention, (b) argues that the categorization rule in the likelihood-based GRT is extremely close in spirit to Nosofsky's (1986) exemplar-based similarity model, (c) reports new model-based analyses that call into question Ashby and Lee's interpretation of their identification-confusion data, (d) raises questions about the identification and similarity models tested by Ashby and Lee, and (e) criticizes Ashby and Lee's methods of fitting and evaluating the various models.

Attention↗

PubMed1993

The paradigm and the fuzzy logical model of perception are alive and well.

Cutting, Bruno, Brady, and Moore (1992) criticized the paradigm for inquiry and the fuzzy logical model of perception (FLMP) presented in Massaro (1988a). In this reply to their remarks, it is shown that (a) the properties of the paradigm are ideal for inquiry; (b) models are best tested against the results of individual subjects and not average group data; (c) model fitting and analysis of variance do not give contradictory results; (d) the FLMP can be proven false and does not have a superpower to predict a plethora of functions or to absorb random variability; and (e) various extraneous characteristics of a model, such as equation length, cannot account for the success of the FLMP. On the other hand, the empirical findings of Cutting et al. give important new properties of pattern recognition. Finally, Cutting's theory of directed perception is compared with the FLMP.

Decision Making↗

PubMed2000

A sampling approach to biases in conditional probability judgments: beyond base rate neglect and statistical format.

Conditional probability judgments of rare events are often inflated. Early accounts assumed a general deficit in using statistical base rates. More recent approaches predict improvement when problems are presented in frequency format or refer to natural categories. The present theory focuses on sampling processes. Experiment 1 showed that a seeming advantage of frequency over probability formats is due to a confounded factor, the need to mentally transform stimulus samples. An information search paradigm was used in Experiment 2. When sampling by the predictor, the probability to be estimated, p(criterion/predictor), was conserved in the samples and judgments were quite accurate. However, when sampling by the criterion, the low base-rate event was strongly overrepresented, accounting for the entire bias. Judgments were quite sensitive to the sampled data, but failed to take sampling constraints into account, as shown in Experiments 3 and 4.

Adult↗

PubMed2000

The importance of frameworks for directing empirical questions: reply to Goodie and Fantino (2000).

A. S. Goodie and E. Fantino (2000) make two main criticisms of the predictions of M. C. Lovett and C. D. Schunn's (1999) RCCL model. (RCCL is pronounced "ReCyCLe"; it stands for Represent the task, Construct a set of action strategies, Choose from among those strategies according to success rate, Learn new success rates.) In both cases, the authors believe the criticisms reflect a failure to appreciate the difference between broad frameworks and specific mathematical/computational models. In this article, the value of a broad framework, such as RCCL, in directing new empirical analyses and guiding theoretical development is shown. In particular, RCCL expands on existing work to reveal how variability and change in mental representations influence base-rate sensitivity. The authors also address several other issues raised by A. S. Goodie and E. Fantino (2000) and show that qualitative shifts in individuals' choice behavior are present in their original data--a key prediction of RCCL that does not appear in previous accounts.

Decision Making↗

PubMed1997

Quantitative models of animal learning and cognition.

This article reviews the prerequisites for quantitative models of animal learning and cognition, describes the types of models, provides a rationale for the development of such quantitative models, describes criteria for their evaluation, and makes recommendations for the next generation of quantitative models. A modular approach to the development of models is described in which a procedure is considered as a generator of stimuli and a model is considered as a generator of responses. The goal is to develop models that, in combination with many different procedures, produce sequences of times of occurrence of events (stimuli and responses) that are indistinguishable from those produced by the animal under many experimental procedures and data analysis techniques.

Animals↗

PubMed1990

List-strength effect: II. Theoretical mechanisms.

Ratcliff, Clark, and Shiffrin (1990) examined the list-strength effect: the effect of strengthening (or weakening) some list items upon memory for other list items. The list-strength effect was missing or negative in recognition, missing or positive in cued recall, and large and positive in free recall. We show that a large number of current models fail to predict these findings. A variant of the SAM model of Gillund and Shiffrin (1984), involving a differentiation hypothesis, can handle the data. A variant of MINERVA 2 (Hintzman, 1986, 1988) comes close but has some problems. Successful variants of a variety of composite and network models were not found (e.g., Ackley, Hinton, & Sejnowski, 1985; Anderson, 1972, 1973; Metcalfe Eich, 1982; Murdock, 1982; Pike, 1984). The results suggest constraints on the future development of such models.

Cues↗

PubMed1986

Age differences in the structure of the Philadelphia Geriatric Center Morale Scale.

In this research we examined age differences in the factorial structure of the Philadelphia Geriatric Center (PGC) Morale Scale. In particular, we viewed the covariance structure of the PGC Morale Scale items as a function of several parameter matrices. We analyzed the factorial invariance by testing hypotheses involving the equivalence constraints of one or more parameter matrices in the young-old (65-74) and the old-old (75 and over) populations. Data for this research came from the 1968 National Senior Citizens Survey. Analysis of covariance structures, or LISREL, was used to assess the factorial invariance of the PGC Morale Scale. Although there are some statistically significant age differences in the factorial structure, substantively they are less important.

Aged↗

PubMed2000

Adult age differences in task switching.

Age differences in 2 components of task-set switching speed were investigated in 118 adults aged 20 to 80 years using task-set homogeneous (e.g., AAAA ...) and task-set heterogeneous (e.g., AABBAABB ... ) blocks. General switch costs were defined as latency differences between heterogeneous and homogeneous blocks. whereas specific switch costs were defined as differences between switch and nonswitch trials within heterogeneous blocks. Both types of costs generalized over verbal, figural, and numeric stimulus materials; were more highly correlated to fluid than to crystallized abilities; and were not eliminated after 6 sessions of practice, indicating that they reflect basic and domain-general aspects of cognitive control. Most important, age-associated increments in costs were significantly greater for general than for specific switch costs, suggesting that the ability to efficiently maintain and coordinate 2 alternating task sets in working memory instead of 1 is more negatively affected by advancing age than the ability to execute the task switch itself.

Adult↗

PubMed2000

Associations among NEO personality assessments and well-being at midlife: facet-level analyses.

The association between well-being and personality was examined in 2,379 middle-aged adults. Measures that parallel C. D. Ryffs (1989) psychological model were selected to assess well-being. The 30 facet scales of the NEO-PI-R were used to measure personality. More than 83% of the facet-well-being correlations within the domains of Neuroticism, Extraversion, and Conscientiousness reached statistical significance, whereas, less than half of the correlations within the domains of Agreeableness and Openness were significant. The facets within each domain demonstrated different patterns of associations with the well-being measures, indicating that facet-level assessments yield additional information.

Attitude↗

PubMed1996

Work-related stress and psychological distress in emergency medical technicians.

Emergency medical technicians (N = 65) participated in a study on work environment characteristics, work-related stress, and psychological distress. Data were collected at baseline and 6 months. Work-related stress was associated with lower work group support and poor supervisory behavior. Work-related stress was strongly related to psychological distress. Changes in work-related stress were significantly related to changes in psychological distress. Findings support the work-related stress, psychological distress model.

Adult↗

PubMed2003

How do respondents construe ambiguous response formats of affect items?

Ambiguous response formats predict correlations from -.467 to -1 between opposite items, depending on whether the respondent's interpretation of the format is unipolar or bipolar. The authors present a procedure to investigate the proper interpretation in each case. It consists of applying nonparametric and parametric item response theory models (the Mokken and the graded response models) to pairs of opposite items in order to find the locations of the response options along the latent scale and, therefore, identify the response format construction. The authors tested this procedure on 4 samples (Ns=142-1,150) and 2 item pairs ("relaxed"-"tense" and "optimistic"-"pessimistic"). The results revealed that respondents constructed the formats as bipolar and supported the bipolarity of the item pairs.

Adult↗

PubMed1989

Choice of structural model via parsimony: a rationale based on precision.

It is shown that, in large samples, the more parsimonious of two competing nested models yields an estimator of the common parameters that has smaller sampling variance. The use of parsimony as a criterion for choice between two otherwise acceptable models can thus be rationalized on the basis of precision of estimation.

Humans↗