Trying to Resolve the Two-Envelope Problem

After explaining the well-known two-envelope paradox by indicating the fallacy involved, we consider the two-envelope problem of evaluating the factual information provided to us in the form of the value contained by the envelope chosen first. We try to provide a synthesis of contributions from economy, psychology, logic, probability theory (in the form of Bayesian statistics), mathematical statistics (in the form of a decision-theoretic approach) and game theory. We conclude that the two-envelope problem does not allow a satisfactory solution. An interpretation is made for statistical science at large.     

Role of grammatical gender and semantics in German word production

Semantic substitution errors (e.g., saying "arm" when "leg" is intended) are among the most common types of errors occurring during spontaneous speech. It has been shown that grammatical gender of German target nouns is preserved in the errors (E. Mane, 1999). In 3 experiments, the authors explored different accounts of the grammatical gender preservation effect in German. In all experiments, semantic substitution errors were induced using a continuous naming paradigm. In Experiment 1, it was found that gender preservation disappeared when speakers produced bare nouns. Gender preservation was found when speakers produced phrases with determiners marked for gender (Experiment 2) but not when the produced determiners were not marked for gender (Experiment 3). These results are discussed in the context of models of lexical retrieval during production.     

Processing modes and parallel processors in producing familiar keying sequences

Recent theorizing indicates that the acquisition of movement sequence skill involves the development of several independent sequence representations at the same time. To examine this for the discrete sequence production task, participants in Experiment 1 produced a highly practiced sequence of six key presses in two conditions that allowed little preparation so that interkey intervals were slowed. Analyses of the distributions of moderately slowed interkey intervals indicated that this slowing was caused by the occasional use of two slower processing modes, that probably rely on independent sequence representations, and by reduced parallel processing in the fastest processing mode. Experiment 2 addressed the role of intention for the fast production of familiar keying sequences. It showed that the participants, who were not aware they were executing familiar sequences in a somewhat different task, had no benefits of prior practice. This suggests that the mechanisms underlying sequencing skills are not automatically activated by mere execution of familiar sequences, and that some form of top-down, intentional control remains necessary.     

SLOT: A research platform for investigating multimodal communication

In this article, we present the spatial logistics task (SLOT) platform for investigating multimodal communication between 2 human participants. Presented are the SLOT communication task and the software and hardware that has been developed to run SLOT experiments and record the participants’ multimodal behavior. SLOT offers a high level of flexibility in varying the context of the communication and is particularly useful in studies of the relationship between pen gestures and speech. We illustrate the use of the SLOT platform by discussing the results of some early experiments. The first is an experiment on negotiation with a one-way mirror between the participants, and the second is an exploratory study of automatic recognition of spontaneous pen gestures. The results of these studies demonstrate the usefulness of the SLOT platform for conducting multimodal communication research in both human-human and human-computer interactions.     

Burgeoning skepticism

This paper shows that the resources mobilized by recent arguments against individualism in the philosophy of mind also suffice to construct a good argument against a Humean-style skepticism about our knowledge of extra-mental reality. The argument constructed, however, will not suffice to lay to rest the attacks of a truly global skeptic who rejects the idea that we usually know what our occurrent mental states are.     

Burhoe's Legacy: Lessons for Europeans

Ralph Burhoe's ideas have not been well received in European Protestant theology. His approach has been at odds with the dominant resistance to natural theology on the Continent, and it has not fit well with reconciling attempts from the United Kingdom either. However, Burhoe's interest in the role of religions in the emergence of human nature and culture, including the interest in noncognitive functions of religion, should be taken to heart. Besides, he has set an example for Europeans with respect to method in dealing with first-rate science.     

Socio-cognitive conflict and structure of individual and collective performances

A previous experiment (Doise, Mugny and Perret-Clermont, 1975) has shown that pairs of subjects perform better on a spatial representation task than subjects alone. As a conclusion the hypothesis was put forward that conflicts of cognitive centrations, embedded in a social situation, lead children to coordinate their centrations. The present research was planned to verify several predictions following from this general hypothesis. Results show that indeed more progress takes place when children with different cognitive strategies work together than when children with the same strategies do so, and that not only the less advanced but also the more advanced child progresses when they interact with each other.