A logistic approach to knowledge structures

Models for quantitative (or numerical) testing like e.g. educational testing have a relatively long tradition in psychology, while the qualitative (or nonnumerical) approach to psychometrics is more recent. The approach presented in this paper can be regarded as an attempt to integrate, to some extent, the numerical and nonnumerical fields. In numerical testing a subject is characterized by some real-valued parameter representing her level or ability. In the nonnumerical approach the knowledge state of an individual is represented by the subset of problems that the individual is capable of solving. We propose a model in which the relationship between the ability levels and the knowledge states is worked out on a probabilistic basis. The central idea is that the ability parameters and the knowledge states are not independent. A logistic model is derived which specifies the probabilities of the knowledge states conditional on the ability levels. We show that the Rasch model arises as a special case of the proposed model.     

Lexicality and stimulus length effects in Italian dyslexics: role of the overadditivity effect.

The effect of lexicality and stimulus length was studied in 32 third- and fourth-grade Italian dyslexics and in 86 age-matched controls. A visual lexical decision task was used. As proposed by Faust et al. (1999), the results were analyzed in terms of raw reaction time (RT) data and using the z-score transformation to control for the presence of overadditivity effects. In terms of RTs, dyslexics showed a larger difference between words and nonwords (lexicality effect) and between short and long stimuli (length effect) than proficient readers. When data were transformed into z scores, only the group by length interaction remained significant while that with lexicality vanished. This pattern indicates that stimulus length has a specific role in Italian dyslexics' reading deficit; in contrast, slowness in responding to nonwords was not specific but was interpreted as one aspect of dyslexics' general inability to deal with alphabetical material (overadditivity effect).     

Mosaic trisomy 20 and mitigation in capital crimes sentencing: A review and case report

Trisomy 20 is a genetic abnormality in which individuals have an extra copy of chromosome 20. Complete trisomy 20 is rare and believed to be incompatible with life. A mosaic form of trisomy 20, in which only some cells or tissues contain the extra chromosome, is a relatively commonly encountered chromosomal abnormality found during prenatal testing, and c. 90% result in a normal phenotype. However, despite the absence of a consistent phenotype, certain findings have been reported across multiple cases of mosaic trisomy 20. These include an array of morphological findings, developmental delays, and learning disabilities. Beyond physical manifestations, a wide range of developmental and learning delays have also been reported. In this work, we provide an overview of the trisomy 20 literature and a case report of a young adult male with mosaic trisomy 20 who committed homicide. His developmental and life history, eventual diagnosis of mosaic trisomy 20, similarities and differences in his condition compared with prior research findings, and potentially new phenotypic findings associated with trisomy 20 that he manifested (childhood visual hallucinations, self‐injury, polydactyly) are presented. Additionally, the potential role of this genetic diagnosis in his neuropsychiatric history and its successful application as a mitigating factor at his capital sentencing trial are described. We did not identify other similar cases during our search of major scientific and legal databases. As a backdrop, the use of genetics in criminal trials is on the rise, and courts are increasingly likely to accept behavioral genetics evidence; therefore, it is crucial that the legal system is well acquainted with the opportunities and limitations of these approaches.     

The semantic specificity of gestures when verbal communication is not possible: The case of emergency evacuation

The aim of the present study was to examine the comprehension of gesture in a situation in which the communicator cannot (or can only with difficulty) use verbal communication. Based on theoretical considerations, we expected to obtain higher semantic comprehension for emblems (gestures with a direct verbal definition or translation that is well known by all members of a group, or culture) compared to illustrators (gestures regarded as spontaneous and idiosyncratic and that do not have a conventional definition). Based on the extant literature, we predicted higher semantic specificity associated with arbitrarily coded and iconically coded emblems compared to intrinsically coded illustrators. Using a scenario of emergency evacuation, we tested the difference in semantic specificity between different categories of gestures. 138 participants saw 10 videos each illustrating a gesture performed by a firefighter. They were requested to imagine themselves in a dangerous situation and to report the meaning associated with each gesture. The results showed that intrinsically coded illustrators were more successfully understood than arbitrarily coded emblems, probably because the meaning of intrinsically coded illustrators is immediately comprehensible without recourse to symbolic interpretation. Furthermore, there was no significant difference between the comprehension of iconically coded emblems and that of both arbitrarily coded emblems and intrinsically coded illustrators. It seems that the difference between the latter two types of gestures was supported by their difference in semantic specificity, although in a direction opposite to that predicted. These results are in line with those of Hadar and Pinchas‐Zamir (2004), which showed that iconic gestures have higher semantic specificity than conventional gestures.     

Between Causes and Reasons: Sellars,Hegel (and Lewis) on “Sensation”

ABSTRACT

This paper explores Sellars’ and Hegel’s treatment of ‘sensation’ – a notion that plays a central role in the reflections of both authors but which has garnered little scholarly attention. To disentangle the issues surrounding the notion and elaborate its role, function, and fate in their thought, I begin with a methodological question: what kind of philosophical argument leads Sellars and Hegel to introduce the concept of ‘sensation’ into their systems? Distinguishing between their two argumentative approaches, I maintain that Hegel offers what I broadly label a ‘transcendental’ argument for ‘sensation,’ which he presents in the Philosophy of Subjective Spirit and in the corresponding Lectures, whereas Sellars introduces the notion of sensation for what I term empirically ‘explanatory’ reasons. Next, I closely analyze Hegel’s and Sellars’ theories of sensation to produce a textually supported and conceptually coherent reading of their views on the notion. To clarify my methodological distinction and its stakes in Hegel’s and Sellars’ I will reference Lewis’ notion of the given.     

Manipulation of responsibility in non-clinical subjects: does expectation of failure exacerbate obsessive-compulsive behaviors?

An exaggerated sense of responsibility is currently considered as the ground for the obsessive-compulsive disorder. Obsessive-like behaviors, such as hesitations and checks, may be induced in non-clinical subjects by increasing perceived responsibility (i.e., perceived personal influence on negative outcomes). In line with Salkovskis' proposal [The cognitive approach to anxiety: threat beliefs, safety-seeking behavior, and the special case of health anxiety and obsessions, in: P.M. Salkovskis (Ed.), Frontiers of Cognitive Therapy, Guilford, New York], we tested the hypothesis that reduced coping abilities (i.e., an exaggerated expectation of failure) are another effectual factor contributing to obsessive-like behaviors. We examined 47 normal volunteers in a visuo-spatial memory task, and manipulated their perceived personal influence and expectation of failure by giving differential instructions and feedback about their performance. Increase of perceived personal influence induced slowness, hesitations and checks without enhancing performance. Expectation of failure exacerbated obsessive-like behaviors, again without affecting performance. These results confirm the role of responsibility in obsessive-like behavior and indicate that reduced coping abilities may contribute to worsen dysfunctional strategies.     

How to hit Scylla without avoiding Charybdis: comment on Perruchet, Tyler, Galland, and Peereman (2004)

M. Pe?a, L. L. Bonatti, M. Nespor, and J. Mehler argued that humans compute nonadjacent statistical relations among syllables in a continuous artificial speech stream to extract words, but they use other computations to determine the structural properties of words. Instead, when participants are familiarized with a segmented stream, structural generalizations about words are quickly established. P. Perruchet, M. D. Tyler, N. Galland, and R. Peereman criticized M. Pe?a et al.'s work and dismissed their results. In this article, the authors show that P. Perruchet et al.'s criticisms are groundless.     

Empirical indistinguishability: From the knowledge structure to the skills

Recent literature has pointed out that the basic local independence model (BLIM) when applied to some specific instances of knowledge structures presents identifiability issues. Furthermore, it has been shown that for such instances the model presents a stronger form of unidentifiability named empirical indistinguishability, which leads to the fact that the existence of certain knowledge states in such structures cannot be empirically tested. In this article the notion of indistinguishability is extended to skill maps and, more generally, to the competence-based knowledge space theory. Theoretical results are provided showing that skill maps can be empirically indistinguishable from one another. The most relevant consequence of this is that for some skills there is no empirical evidence to establish their existence. This result is strictly related to the type of probabilistic model investigated, which is essentially the BLIM. Alternative models may exist or can be developed in knowledge space theory for which this indistinguishability problem disappears.     

Down But Not Yet Out: Depression,Political Efficacy,and Voting

Depression is one of the most common health problems in the developed world. Previous research has primarily investigated the relationship between depression and voting, largely overlooking its cognitive foundations. We turn to political efficacy as a key political attitude and precondition for political engagement. We build on research into the cognitive aspects of depression to construct arguments linking depression, political efficacy, and voting. Using cross-sectional (European Social Survey) and longitudinal (U.K. Household Longitudinal Study) data, we find evidence for a negative relationship between depression and political efficacy, that depression reduces external but not necessarily internal political efficacy, and for an accumulation effect of depression on (external) political efficacy. We also show that political efficacy is a crucial mechanism for the depression–voting gap. Our research has important implications for political representation.     

Children's use of conversational rules in a referential communication task

Three experiments investigating first-grade children's comprehension, of referentially ambiguous messages are reported. In the first one children were shown to interpret a literally ambiguous message by means of the strategy based on the conversational Maxim of Antecedent rather than that based on the more appropriate Maxim of Quantity. The results of the second experiment suggest that the Maxim of Quantity can be used by children, provided the situation is quite simple; they also suggest that after having used such a maxim in a simple situation, children can apply it in a more complex situation. This generalization to new situations, however, is not a mere perseveration since, as shown in the third experiment, children can adjust their comprehension strategy to the situation requirements. The results are discussed with reference to the recent proposals on referential ambiguity and children communication failures.