Some effects of epistemological structure on memory

Graph theoretical models of the epistemological structure imposed upon a set of mathematical concepts by Ss’ definitions of them were constructed. Three graphical characteristics of the models were manipulated in a series of experiments to assess their effects on recall. Experiment I showed that recall and confidence of recall were highest for concept pairs connected by short paths, next highest for those connected by long paths, and lowest for those not connected by paths. Experiment II replicated the result of Experiment I that recall and confidence of recall were greater for concept pairs connected by paths than for those not connected by paths and revealed no differences in recall between concept pairs connected by many paths and those connected by a few paths. Experiment III found no differences in recall of abstract and concrete concepts, The abstractness of a concept was quantified by the mean path length from the concept to primitive (undefined) concepts. The approach of building a model of each S’s epistemological structure was supported by the finding that, while a given. S’s definitions of the concepts remained relatively constant, there were considerable differences in definitions of the concepts between Ss.     

Isolated and interrelated concepts

A continuum between purely isolated and purely interrelated concepts is described. Along this continuum, a concept is interrelated to the extent that it is influenced by other concepts. Methods for manipulating and identifying a concept’s degree of interrelatedness are introduced. Relatively isolated concepts can be empirically identified by a relatively large use of nondiagnostic features, and by better categorization performance for a concept’s prototype than for a caricature of the concept. Relatively interrelated concepts can be identified by minimal use of nondiagnostic features, and by better categorization performance for a caricature than for a prototype. A concept is likely to be relatively isolated when subjects are instructed to create images for their concepts rather than find discriminating features, when concepts are given unrelated labels, and when the categories that are displayed alternate rarely between trials. The entire set of manipulations and measurements supports a graded distinction between isolated and interrelated concepts. The distinction is applied to current models of category learning, and a connectionist framework for interpreting the empirical results is presented.     

When groups are more competitive than individuals: the domain of the discontinuity effect

The related goals of the research were to delineate the domain of discontinuity, 1st by demonstrating its occurrence in a nonmatrix situation and, 2nd, by establishing the antecedent outcome conditions necessary for producing a discontinuity effect. The 1st goal was met by designing a mixed motive situation involving the production of origami products. Under these conditions, the magnitude of the discontinuity effect did not significantly differ from that in a matrix-only condition. The 2nd goal was met by a separate experiment that used H. H. Kelley and J. W. Thibaut's (1978) analysis of degree of noncorrespondence of outcomes. This experiment demonstrated that as noncorrespondence increased, so did the rate of competitive responding by groups but not by individuals. This pattern was qualified by an interaction with gender such that competitiveness was more markedly affected by noncorrespondence for groups of women than for groups of men.     

A general factor in improvement with practice

Results of 10 trials on 6 tests for 50 subjects were analyzed, first, by applying the centroid method to actual improvement or practice scores and, second, by applying a formula developed by Woodrow for determining factor loadings for practice scores from the differences between factor loadings of initial and final scores. Contrary to expectation, the two methods yielded discrepant results, for the explanation of which a hypothesis is advanced. The operation of a general factor was not demonstrated. Tentative interpretations of the factors extracted by the centroid method are offered.     

Grouping Effects on Spatial Attention in Visual Search

In visual search tasks, spatial attention selects the locations containing a target or a distractor with one of the target's features, implying that spatial attention is driven by target features (M.S. Kim & K. R. Cave, 1995). The authors measured the effects of location-based grouping processes in visual search. In searches for a color-shape combination (conjunction search), spatial probes indicated that a cluster of same-color or same-shape elements surrounding the target were grouped and selected together. However, in searches for a shape target (feature search), evidence for grouping by an irrelevant feature dimension was weaker or nonexistent. Grouping processes aided search for a visual target by selecting groups of locations that shared a common feature, although there was little or no grouping by an irrelevant feature when the target was defined by a unique salient feature.     

Interference with visual short-term memory

Working memory (Baddeley and Hitch 1974) incorporates the notion of a visuo-spatial sketch pad; a mechanism thought to be specialized for short-term storage of visuo-spatial material. However, the nature and characteristics of this hypothesized mechanism are as yet unclear. Two experiments are reported which examined selective interference in short-term visual memory. Experiment 1 contrasted recognition memory span for visual matrix patterns with that for visually presented letter sequences. These two span tasks were combined with concurrent arithmetic or a concurrent task which involved manipulation of visuo-spatial material. Results suggested that although there was a small, significant disruption by concurrent arithmetic of span for the matrix patterns, there was a substantially larger disruption of the letter span task. The converse was true for the secondary visuo-spatial task. Experiment 2 combined the span tasks with two established tasks developed by Brooks (1967). Span for matrix patterns was disrupted by a visuo-spatial task but not by a secondary verbal task. The converse was true for letter span. These results suggest that the impairment in short-term visual memory resulting from secondary arithmetic reflects a small general processing load, but that the selective interference due to mode of processing is by far the stronger effect. Results are interpreted as being entirely consistent with the notion of a specialized visuo-spatial mechanism in working memory.     

Grouping effects on spatial attention in visual search.

In visual search tasks, spatial attention selects the locations containing a target or a distractor with one of the target's features, implying that spatial attention is driven by target features (M.-S. Kim & K. R. Cave, 1995). The authors measured the effects of location-based grouping processes in visual search. In searches for a color-shape combination (conjunction search), spatial probes indicated that a cluster of same-color or same-shape elements surrounding the target were grouped and selected together. However, in searches for a shape target (feature search), evidence for grouping by an irrelevant feature dimension was weaker or nonexistent. Grouping processes aided search for a visual target by selecting groups of locations that shared a common feature, although there was little or no grouping by an irrelevant feature when the target was defined by a unique salient feature.     

Zur Qualit?t forensischer Gutachten aus strafrechtlicher Sicht

The paper describes the requirements, both regulatory and developed by court decisions that have to be fulfilled by expert witnesses in criminal cases. It emphasizes the borderline between (psycho) science and law, names sources of mistakes made by experts and the reasons and shows some results caused by bad expertise. A much better basic and advanced training of experts is demanded for experts as well as for judges, prosecutors and prison officers and calls for a new culture for a mutual exchange of dialogue.     

Bootstrap approach to inference and power analysis based on three test statistics for covariance structure models

We study several aspects of bootstrap inference for covariance structure models based on three test statistics, including Type I error, power and sample‐size determination. Specifically, we discuss conditions for a test statistic to achieve a more accurate level of Type I error, both in theory and in practice. Details on power analysis and sample‐size determination are given. For data sets with heavy tails, we propose applying a bootstrap methodology to a transformed sample by a downweighting procedure. One of the key conditions for safe bootstrap inference is generally satisfied by the transformed sample but may not be satisfied by the original sample with heavy tails. Several data sets illustrate that, by combining downweighting and bootstrapping, a researcher may find a nearly optimal procedure for evaluating various aspects of covariance structure models. A rule for handling non‐convergence problems in bootstrap replications is proposed.     

Maximum marginal likelihood estimation for semiparametric item analysis

The item characteristic curve (ICC), defining the relation between ability and the probability of choosing a particular option for a test item, can be estimated by using polynomial regression splines. These provide a more flexible family of functions than is given by the three-parameter logistic family. The estimation of spline ICCs is described by maximizing the marginal likelihood formed by integrating ability over a beta prior distribution. Some simulation results compare this approach with the joint estimation of ability and item parameters.IRCAMThe research reported in this paper was supported by Grants APA320 and A4035 from the Natural Sciences and Engineering Research Council of Canada. It was also supported by Contract No. F41689-82-C-10020 from the Air Force Human Resources Laboratory to Educational Testing Service. The author wishes to thank M. Abrahamowicz for his assistance and R. Darrell Bock for providing the parameters for the items used in the simulations.     

Objective Similarity and Mental Representation

The claim that similarity plays a role in representation has been philosophically discredited. Psychologists, however, routinely analyse the success of mental representations for guiding behaviour in terms of a similarity between representation and the world. I provide a foundation for this practice by developing a philosophically responsible account of the relationship between similarity and representation in natural systems. I analyse similarity in terms of the existence of a suitable homomorphism between two structures. The key insight is that by restricting attention to only those homomorphisms induced by causal processes, we can solve two philosophical problems with a single assumption. First, causal structure provides an adequate source for the bias required to ensure the similarity relation is non-trivial; second, it provides an adequate source for the directionality required to move from similarity to representation. I defend this account against objections by Goodman and van Fraassen and demonstrate that it is indeed the account of similarity's role in representation assumed by psychological practice.     

Participation by women in developmental, social, cognitive, and general psychology: A context for interpreting trends in behavior analysis

We examined participation by women in journals devoted to social, developmental, cognitive, and general psychology. Authorship and first authorship by women increased from 1978 to 1997 for most journals. Participation by women on the editorial staff did not keep pace with their increased authorship for social and developmental psychology. Based on these trends, women's participation decreased with increases in the selectivity of the position for social and developmental psychology (a glass ceiling). The development of a glass ceiling suggests that the contributions of men and women are not always treated equally (gender inequity). Because a similar glass ceiling was reported for journals in behavior analysis (McSweeney, Donahoe, & Swindell, 2000; McSweeney & Swindell, 1998), the causes of this inequity appear to be relatively widespread. The failure to find a glass ceiling for general and cognitive psychology suggests that the inequity might be reduced by subtle pressure for diversity in editorial positions and by adopting actions that encourage women to pursue research positions.     

Attentional capture by irrelevant emotional distractor faces is contingent on implicit attentional settings

Although expressions of facial emotion hold a special status in attention relative to other complex objects, whether they summon our attention automatically and against our intentions remains a debated issue. Studies supporting the strong view that attentional capture by facial expressions of emotion is entirely automatic reported that a unique (singleton) emotional face distractor interfered with search for a target that was also unique on a different dimension. Participants could therefore search for the odd-one out face to locate the target and attentional capture by irrelevant emotional faces might be contingent on the adoption of an implicit set for singletons. Here, confirming this hypothesis, an irrelevant emotional face captured attention when the target was the unique face with a discrepant orientation, both when this orientation was unpredictable and when it remained constant. By contrast, no such capture was observed when the target could not be found by monitoring displays for a discrepant face and participants had to search for a face with a specific orientation. Our findings show that attentional capture by emotional faces is not purely stimulus driven and thereby resolve the apparent inconsistency that prevails in the literature on the automaticity of attentional capture by emotional faces.     

A wood-gnawing sensor for recording collateral behavior emitted by rats on differential reinforcement of low rate schedules

The difficulties in measuring the idiosyncratic collateral behavior emitted by rats on a DRL schedule are overcome by providing woodblocks attached to a sensor. Wood gnawing is recorded by stylus transducer signals. An audio amplifier raises these signals to a suitable level for the operation of a threshold control unit. A pulse former operates the final relay amplifier for 150 msec from the onset of disturbance to the transducer.     

Well-being and Need for Support of Adolescents with a Chronically Ill Family Member

This study investigates whether there are differences in the well-being, need for help and use of support services between adolescents with and without a chronically ill or disabled family member. It also examines the role played by the type of illness, the relationship to the family member and the nature and intensity of the help provided by the adolescent. A Dutch sample of 1581 adolescents (average age 14.6?years) completed a questionnaire in 2010 about mental health problems, pro-social behavior, need for and use of support and the illness of family members and any care tasks performed by the respondent. Young people with a sick family member had more mental health problems than their counterparts without a chronically ill family member. They also reported a greater need for and use of help and support. Performing domestic tasks was found to be a predictor for overall mental health problems. The intensity of the help given was related to the need for help by the adolescent. It is concluded that growing up with a chronically ill family member and spending a lot time performing (domestic) tasks are risk factors for adolescent mental health problems and adolescents’ need for help. Special attention is warranted for those who need support but who do not translate that need into reality by seeking help.     

The effects of scene inversion on change blindness

In two experiments, participants searched for a difference between two views of a scene. In Experiment 1, the authors extended the change-blindness findings from previous work by R. A. Rensink, J. K. O'Regan, and J. J. Clark (1997), which used an experimenter-induced global transient, to a less artificial situation in which participants searched for a difference in a pair of photographic images presented simultaneously. To examine the idea that meaning-driven endogenous orienting was responsible for the previously observed advantage for changes in center-of-interest items, the authors inverted half of the image pairs. The advantage for center-of-interest items was replicated with upright displays, but it was completely eliminated by inversion, strongly supporting the role of meaning-driven endogenous orienting in this task. With flickering displays (Experiment 2), the center-of-interest effect was completely unaffected by inversion. The authors suggest that when change blindness is induced via flicker, scene modifications are typically found by stimulus-driven rather than by meaning-driven processes.     

Interfacing Apple and IBM computers for the analysis of clinical biofeedback

This paper demonstrates a method of transferring research data from a remote clinic to a large university mainframe for data manipulation and statistical analysis. Data collected by an Apple //e computer were transferred to an IBM 3031 mainframe by sending data files to an IBM PC by telephone modem or by direct hardwire connection to the PC. The IMB PC performed data-formatting routines and then uploaded the files to the mainframe for storage. Advantages and disadvantages of sending data over telephone lines via a modem are discussed.     

The monadic second-order logic of graphs XV: On a conjecture by D. Seese

A conjecture by D. Seese states that if a set of graphs has a decidable monadic second-order theory, then it is the image of a set of trees under a transformation of relational structures defined by monadic second-order formulas, or equivalently, has bounded clique-width. We prove that this conjecture is true if and only if it is true for the particular cases of bipartite undirected graphs, of directed graphs, of partial orders and of comparability graphs. We also prove that it is true for line graphs, for interval graphs and for partial orders of dimension 2. Our treatment of certain countably infinite graphs uses a representation of countable linear orders by binary trees that can be constructed by monadic second-order formulas. By using a counting argument, we show the intrinsic limits of the methods used here to handle this conjecture.