Hierarchical classes: Model and data analysis

A discrete, categorical model and a corresponding data-analysis method are presented for two-way two-mode (objects × attributes) data arrays with 0, 1 entries. The model contains the following two basic components: a set-theoretical formulation of the relations among objects and attributes; a Boolean decomposition of the matrix. The set-theoretical formulation defines a subset of the possible decompositions as consistent with it. A general method for graphically representing the set-theoretical decomposition is described. The data-analysis algorithm, dubbed HICLAS, aims at recovering the underlying structure in a data matrix by minimizing the discrepancies between the data and the recovered structure. HICLAS is evaluated with a simulation study and two empirical applications.This research was supported in part by a grant from the Belgian NSF (NFWO) to Paul De Boeck and in part by NSF Grant BNS-83-01027 to Seymour Rosenberg. We thank Iven Van Mechelen for clarifying several aspects of the Boolean algebraic formulation of the model and Phipps Arabie for his comments on an earlier draft.     

Semantic priming effects from single words in a lexical decision task

The present research examines the semantic priming effects of a centrally presented single prime word to which participants were instructed to either "attend and remember" or "ignore". The prime word was followed by a central probe target on which the participants made a lexical decision task. The main variables manipulated across experiments were prime duration (50 or 100 ms), the presence or absence of a mask following the prime, and the presence (or absence) and type of distractor stimulus (random set of consonants or pseudowords) on the probe display. There was a consistent interaction between the instructions and the semantic priming effects. Relative to the "attend and remember" instruction, an "ignore" instruction produced reduced positive priming from single primes presented for 100 ms, irrespective of the presence or absence of a prime mask, and regardless of whether the probe target was presented with or without distractors. Additionally, reliable negative priming was found from ignored primes presented for briefer durations (50 ms) and immediately followed by a mask. Methodological and theoretical implications of the present findings for the extant negative priming literature are discussed.     

Is masked neighbor priming inhibitory? Evidence using the incremental priming technique

To investigate neighbor effects in visual word recognition, the masked priming technique holds considerable advantages over unprimed methods, because a target word is used as its own control. However, inhibitory neighbor effects obtained with masked priming are still open for different interpretations, because the primes differ across conditions. Given this theoretical problem, it is useful to investigate neighbor priming effects using a prime as its own control. This option is available in the incremental priming technique (Jacobs, Grainger, & Ferrand, 1995), in which a within-condition baseline is created by comparing the response times (RTs) to a target when it is primed at different prime durations. In this study, we examined masked neighbor priming using this technique. Both the traditional and the within-condition baseline indicated that masked neighbor word priming is inhibitory in nature. The results are discussed in terms of current theories of visual word recognition.     

Sequence skill learning in persons who stutter: implications for cortico-striato-thalamo-cortical dysfunction

The basal ganglia and cortico-striato-thalamo-cortical connections are known to play a critical role in sequence skill learning and increasing automaticity over practice. The current paper reviews four studies comparing the sequence skill learning and the transition to automaticity of persons who stutter (PWS) and fluent speakers (PNS) over practice. Studies One and Two found PWS to have poor finger tap sequencing skill and nonsense syllable sequencing skill after practice, and on retention and transfer tests relative to PNS. Studies Three and Four found PWS to be significantly less accurate and/or significantly slower after practice on dual tasks requiring concurrent sequencing and colour recognition over practice relative to PNS. Evidence of PWS’ deficits in sequence skill learning and automaticity development support the hypothesis that dysfunction in cortico-striato-thalamo-cortical connections may be one etiological component in the development and maintenance of stuttering.

Educational objectives: As a result of this activity, the reader will: (1) be able to articulate the research regarding the basal ganglia system relating to sequence skill learning; (2) be able to summarize the research on stuttering with indications of sequence skill learning deficits; and (3) be able to discuss basal ganglia mechanisms with relevance for theory of stuttering.     

A Note on the Aesthetics of Mirror Reversal

According to Roy Sorensen [Philosophical Studies 100 (2000) 175–191] an object cannot differ aesthetically from its mirror image. On his view, mirror-reversing an object – changing its left/right orientation – cannot bring about any aesthetic change. However, in arguing for this thesis Sorensen assumes that aesthetic properties supervene on intrinsic properties alone. This is a highly controversial assumption and nothing is offered in its support. Moreover, a plausible weakening of the assumption does not improve the argument. Finally, Sorensen’s second argument is shown to be formally flawed. As a result, the case for the aesthetic irrelevancy of orientation seems still open.     

A conceptual and theoretical analysis of evaluative conditioning

Evaluative conditioning is best defined as an effect, that is, as a change in the valence of a stimulus that results from pairing the stimulus with another stimulus. This definition has several advantages that are made explicit in this paper. One of the advantages is that it clarifies that evaluative conditioning can be due to multiple processes. Therefore, the conditions under which evaluative conditioning is observed can depend on the processes that underlie a particular manifestation of evaluative conditioning. This could explain why there are so many conflicting results about the conditions under which evaluative conditioning can be found. Future research should adopt a meta-conditional approach that focuses not only on whether a certain condition is crucial for obtaining evaluative conditioning but should also examine when a certain condition is crucial.     

Internal structure and standardised scores of the Torrance Test of Creative Thinking

The present work sets out to study the internal structure of the Torrance Test of Creative Thinking (TTCT) and to establish standardised scores that will enable the test to be used in both a diagnostic and educational context. 649 students (319 girls and 330 boys), aged 5 to 12 years from various schools in Murcia and Alicante (SE Spain), took part in the study. The findings suggest that the psychometric characteristics of TTCT are satisfactory, and its internal structure can be attributed to three factors that are responsible for a high percentage of the variance (73.8%). The standardised score tables, which are provided for first time in this context, will be useful in the evaluation of creativity and the identification of students with high intellectual abilities.     

The commitment of young soccer players

The main purpose of this study was to test the Sport Commitment Model in young soccer players. Participants' ( N = 437) age ranged from 14 to 16 years. Based on the sport commitment model proposed by Scanlan and colleagues, 6 scales and 28-items constitute the Sport Commitment Questionnaire (SCQ). Results of this study provide some support for the reliability and validity of the SCQ, using a sample of young soccer players. Reliability analysis provided acceptable internal consistency for four scales: Sport Commitment, Sport Enjoyment, Involvement Alternatives and Social Constraints. Sport Enjoyment (Beta= .56, p <.001) and Involvement Alternatives (Beta= -.40, p <.001) were the strongest sport commitment predictors. Further studies with a broader age range, different genders, and other sports or competitive levels are required to continue analyzing the sport commitment model.