Bayesian theories of conditioning in a changing world

The recent flowering of Bayesian approaches invites the re-examination of classic issues in behavior, even in areas as venerable as Pavlovian conditioning. A statistical account can offer a new, principled interpretation of behavior, and previous experiments and theories can inform many unexplored aspects of the Bayesian enterprise. Here we consider one such issue: the finding that surprising events provoke animals to learn faster. We suggest that, in a statistical account of conditioning, surprise signals change and therefore uncertainty and the need for new learning. We discuss inference in a world that changes and show how experimental results involving surprise can be interpreted from this perspective, and also how, thus understood, these phenomena help constrain statistical theories of animal and human learning.     

Collaborative remembering of emotional events: the case of Rabin's assassination

Individual and collaborative remembering of the assassination of Israel's Prime Minister, Itzhak Rabin, were compared. In line with previous laboratory findings on memory of neutral stimuli, it was hypothesised that collaborative remembering (three individuals reaching a common response) and nominal remembering (three individual responses pooled together) of the assassination would be more accurate than individual remembering. A total of 146 participants responded (115 individually and 120 in groups of three) to open-ended and multiple-choice questionnaires (among them, 89 responded twice with a week of intertest interval) about Rabin's assassination and the events that preceded and followed it. Data analysis showed that the collaborative responses to the open-ended questionnaire contained more details (both accurate and inaccurate) than the individual responses, and that the responses to the multiple-choice questionnaire were more accurate than the individual responses. However, the collaborative responses contained fewer details (both accurate and inaccurate) than the nominal responses. Responses to the two questionnaires were more accurate on the retest when they followed collaborative rather than individual responses on the original test. The inferiority of the collaborative relative to the nominal remembering was attributed to collaborative inhibition, whereas the positive effect of collaborative remembering on performance on the retest was attributed to the contribution of contextual cues.     

Benjamin Nathans, <Emphasis Type="Italic">Beyond the Pale: The Jewish Encounter with Late Imperial Russia</Emphasis>. Berkeley: University of California Press, 2002, 424 pp.

Review Essay

Benjamin Nathans, Beyond the Pale: The Jewish Encounter with Late Imperial Russia. Berkeley: University of California Press, 2002, 424 pp.     

Some discriminative properties of fixed ratio performance in the pigeon

The discriminative control over a spatial choice response exercised by prior behavior was studied using a procedure involving discrete exposures to a two-member chained schedule. The initial member (red key) was either a smaller or larger fixed ratio (Mix FR:FR), the completion of which produced, after a 1-sec delay, two white response keys. If the larger FR had been completed as the initial chain member, a single peck on the right white key was reinforced; after the smaller FR, a peck on the left white key was reinforced. Frequencies of unreinforced responses (S(Delta) responses) were determined with several pairs of red-key FRs: 95-5, 75-25, 65-35, 60-40, 58-42 and 50-50. The S(Delta) response frequencies were low through the FR pair 65-35; sharp increases were obtained with pairs 60-40 and 58-42. Later, curves analogous to stimulus generalization functions were obtained using a probe procedure. Finally, the delay interval between completion of a red-key FR and the white-key choice response was manipulated: results were variable, but S(Delta) response frequencies tended to increase with increasing delays.     

The Systematicity of Davidson’s Anti-skeptical Arguments

Topoi - Donald Davidson contributed more deeply to our understanding of language, thought, and reality than perhaps any other recent philosopher. His discussions of skepticism are sometimes seen as...     

A system for controlling the light output of a monochromator by any simple function and for temporally modulating the intensity

This paper describes an apparatus that controls the output of a monochromator so that the energies in each waveband can be equated according to any desired function. A photocell monitors the light from the monochromator and provides a feedback to the power supply driving the lamp. A function generatoris mechanically linked to the monochromator’s wavelength drive and provides the function for correcting the output spectrum. Once set, the light output remains constant even if the bulb ages or is replaced. If desired, a sinusoidalripple of variable frequency and amplitude can be imposed on the mean intensity of the light.     

Cultural phenomena and the research enterprise: Toward a culturally anchored methodology

Highlights the points at which culture intersects major phases of the research enterprise — problem formulation, population definition, concept and measurement development, research design, methodology, and data analysis — and influences and constrains what researchers deem worthy of investigation and how they interpret what they observe. These ethnocentric biases inhibit the development of a knowledge base for understanding diverse cultural communities. At each step of the research process, the need to carefully examine and expose the underlying cultural assumptions and to generate and develop alternative choices is emphasized. Guidelines are provided to encourage researchers to be aware of and deliberately make choices toward the development of a culturally anchored methodology that balances the demands for rigor and sensitivity.