On decidable consequence operators

The main theorem says that a consequence operator is an effective part of the consequence operator for the classical prepositional calculus iff it is a consequence operator for a logic satisfying the compactness theorem, and in which every finitely axiomatizable theory is decidable.     

Identification with an aggressor or a victim and its relation to creativity

Studied identification using a meta-contrast design. The first stimulus was the word 'I'. The second stimulus depicted an aggressor and a victim facing each other. The subliminal 'I' was flashed on either the victim or on the aggressor, or completely withheld. The subjects were 33 school children, aged 10–12 years. They also took a percept-genetic (PG) test of creativity, measuring willingness to return to and recognize early conceptions of a stimulus picture (a still-life). The results showed that the creative children reacted with less anxiety and defense when manipulated to identify with the aggressor than with the victim. The uncreative children showed the opposite reaction, namely a preference for the passive, surrendering victim.     

Latent trait models and dichotomization of graded responses

This paper discusses thecompatibility of the polychotomous Rasch model with dichotomization of the response continuum. It is argued that in the case of graded responses, the response categories presented to the subject are essentially an arbitrary polychotomization of the response continuum, ranging for example from total rejection or disagreement to total acceptance or agreement of an item or statement. Because of this arbitrariness, the measurement outcome should be independent of the specific polychotomization applied, for example, presenting a specific multicategory response format should not affect the measurement outcome. When such is the case, the original polychotomous model is called compatible with dichotomization.A distinction is made between polychotomization or dichotomization before the fact, that is, in constructing the response format, and polycho- or dichotomization after the fact, for example in dichotomizing existing graded response data.It is shown that, at least in case of dichotomization after-the-fact, the polychotomous Rasch model is not compatible with dichotomization, unless a rather special condition of the model parameters is met. Insofar as it may be argued that dichotomization before the fact is not essentially different from dichotomization after the fact, the value of the unidimensional polychotomous Rasch model is consequently questionable. The impact of our conclusion on related models is also discussed.     

Controversies and existence claims in chemistry: The theory of resonance

Controversies, i.e., multiple theory confrontations, may have a strong impact on the development of science. By an analysis of the so-called “resonance controversy” in chemistry the view that controversies and their resolution differ considerably from the process of theory succession is defended. It is argued that controversies are symptomatic of foundational problems, produce theory-scattering or domain-splitting, and induce ontological shifts. An explication is given of the role of existence claims and the applicability of Ockham's Razor in the resolution of controversies. The requirement of a realistic interpretation of theories at all times, as defended by some philosophers, is criticised.     

An investigation of the ability to process inferences in language following right hemisphere brain damage

Twenty-two right hemisphere brain-damaged and 22 non-brain-damaged patients were given a multiple-choice recognition task which contained true statements, statements which were inferentially true but not actually heard before, and false statements. It was hypothesized that if right hemisphere brain damage disturbs the ability to comprehend inferences, these subjects, unlike their normal counterparts, would not falsely recognize true inferences as heard before. This hypothesis was not confirmed. However, the right hemisphere group was poorer than controls at rejecting false statements. This behavior was speculated to be a retrieval difficulty, which was exacerbated if the information contained spatial or semantically similar material.     

Perceptual organization of behavior: a hierarchical control model of coordinated action

The behavior of individual subjects is compared with a hierarchical control system model of behavioral organization. Subjects varied the position of two control handles simultaneously to keep the distance constant between two pairs of lines. Three variations on this basic experiment that illustrate some fundamental properties of coordinated action are shown: first, how independent actions, compensating for unpredictable and undetectable disturbances, can produce a single behavioral result; second, how the ability to produce a particular result is maintained when the connection between action and result is changed; and third, how two independent outputs can appear to be related as coordinative structures when one output disturbs a result being controlled by the other. The correlation between the behavior of subjects and model in all experiments is typically on the order of .99. A detailed examination of the operation of the model shows that actions are structured by perception, not by central commands or equations of constraint.     

Iconic memory, location information, and partial report

It has been suggested that the systematic decline of partial report as the delay of the partial-report cue increases is due to a time-related loss of location information. Moreover, the backward masking effect is said to be precipitated by the disruption of location information before and after identification. Results from three experiments do not support these claims when new indices of location information and of item information are used. Instead, it was found that the systematic decline in partial report was due to a time-related loss of item information, and location information was affected neither by the delay of the partial-report cue nor by the delay of backward masking. Subjects adopted the "select-then-identify" mode of processing.