Maximum likelihood estimation for Luce's choice model

A terminology for general choice models based on the choice axiom is given. It applies to all kinds of choice experiments, such as confusion choice experiments, paired comparisons, triadic comparisons, directional rankings, scores on binary test items, and others. Maximum likelihood estimation for such general choice models is considered. Conditions for the uniqueness of maximum likelihood estimates are given, and it is shown that the estimates can be derived by iterative proportional fitting. This offers the opportunity of a general test of the choice axiom for all kinds of choice experiments using the likelihood ratio. The estimation and testing procedure is applied to data from a form recognition experiment, reported by W. A. Wagenaar (Nederlands Tijdschrift voor de Psychologie, 1968, 23, 96–108).     

Multiple Religious Belonging among visitors of Dominican spiritual centers in the Netherlands

ABSTRACT

In the religiously pluralized Western world, a trend called ‘Multiple Religious Belonging’ (MRB) has been identified. Although it is a much theologically debated concept, empirical research on the practice of MRB is limited. The present research project therefore explores the phenomenon of MRB among visitors of Dominican spiritual centers in the Netherlands (n=472). It investigates to what extent and in which ways such visitors combine elements from more than one religious tradition in their lives and what they perceive to be the benefits of combining elements. It links this information to their views on religion, the resources they draw from, their (religiously diverse) networks, and their motivations for attending spiritual activities. The results indicate that respondents who combine elements from more than one religious tradition (‘combiners’) are more likely than ‘non-combiners’ to: a) see religion as something that is constantly changing during the life course; b) have networks which are religiously diverse; c) place importance on nature, in-depth conversations, personal rituals or practices, and theological, philosophical, and spiritual texts as resources; d) be motivated to attend spiritual centers because of a focus on self-exploration.     

Cognitive determinants of lactate-induced anxiety

The effects of lactate infusion on subjective mood change were studied in two differently instructed groups, in a double-blind, placebo-controlled, cross-over study. Ss who were told that infusions would produce anxiety reported a significant change in the expected direction after lactate but not after glucose. Ss who were told that infusions would produce a state of pleasant excitement showed no change after either infusion. The possible role of cognitive parameters in experimentally-induced anxiety is discussed.     

Substance P facilitation of memory: effects in an appetitively motivated learning task

Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals.     

The paradox of phase transitions in the light of constructive mathematics

Synthese - The paradox of phase transitions raises the problem of how to reconcile the fact that we see phase transitions happen in concrete, finite systems around us, with the fact that our best...