A blueprint of ELI: A new method for eliciting subjective probability distributions

A blueprint of a new method for eliciting uncertain knowledge about continuous quantities is presented. The direct realization of a proper scoring rule in a graphically oriented interactive computer program is one of the central features of the new elicitation methodology. Uncertain knowledge is internally represented through subjective probability distributions. However, in its interaction with assessors, the elicitation method uses a score representation. A proper scoring rule is applied to transform probability density functions into score functions. In order to study its merits, central ideas for the new method were implemented in an experimental version of the elicitation technique ELI. The results were promising and encouraged further development of the technique.     

A technique for measuring thermoregulatory behavior in the fish

Apparatus and procedure are described for studying thermoregulatory behavior in fish. Results obtained with rainbow trout suggest that the described apparatus has several advantages over previously utilized devices.     

A maximum motion technique for assessment of color vision defects

Several luminance-matching methods, such as flicker fusion and the minimum motion technique (MMT), are capable of detecting certain forms of abnormal color vision. We present evidence that the heterochromatic fusion nystagmus (HFN) luminance matching technique can discriminate among normal trichromats, protanopes, and deuteranomals. The HFN luminance matching technique has the advantage that it provides a positive indication of isoluminance (maximization of motion) as opposed to the MMT and flicker fusion methods, which indicate isoluminance by the minimization of motion and flicker, respectively. We tested 16 normal trichromats, 6 protanopes, and 4 deuteranomals with the HFN technique. Results indicate that HFN is a useful tool for examining color vision. Because the HFN stimulus elicits reflexive eye movements (optokinetic nystagmus) that follow the apparent motion of the stimulus, HFN luminance matching will be particularly useful in animal and infant research, where other color vision tests are difficult to implement.     

A new technique for investigating the feeling of knowing

Previous investigations of the feeling of knowing (FOK) have relied on absolute FOK judgements rather than on relative FOK judgments. This has resulted in a confounding of (1) the subject's metamemorial knowledge of nonrecalled items with (2) the subject's know/don't-know threshold. The new technique replaces the absolute FOK judgments with relative FOK judgments in which the subject generates (via paired comparisons) a FOK rank order of nonrecalled items in terms of the predicted likelihood of recognition. This new technique eliminates the aforementioned confounding, provides a richer data base, and yields separate estimates of FOK validity and FOK reliability.     

A simplified technique for conditioning respiratory mouth movements in fish

This report describes a simple technique and restraining device for investigating classically conditioned inhibition of respiration in the fish. The restraining device is seen as having wide applicability for investigations which necessitate the immobilization of the S.     

A new scaling technique for absolute judgments

The results of an experiment using the method of absolute judgments can be viewed as a matrix of conditional probabilities in which the rows represent stimuli and the columns responses. The cosine of the angle between two row vectors is a measure of the similarity of the corresponding stimuli. This cosine provides the basis for a method of scaling the stimuli. Unlike the method of paired comparisons, this new technique does not require arbitrary fixing of a unit of measurement. A numerical example is given.     

Eye as a key element of conspecific image eliciting lateralized response in fish

Visual lateralization in different aspects of social behaviour has been found for numerous species of vertebrates ranging from fish to mammals. For inspection of a shoal mate, many fishes show a left eye–right hemisphere preference. Here, we tested the hypothesis that in fish, there is a key cue in the conspecific appearance, which elicits lateralized response to the whole image of the conspecific. In a series of eight experiments, we explored eye preferences in cryptic-coloured Amur sleeper, Perccottus glenii, fry. Fish displayed left-eye preferences at the population level for inspection of a group of conspecifics, their own mirror image, and a motionless flat model of a conspecific. In contrast, no population bias was found for scrutinizing an empty environment or a moving cylinder. When fry were showed a model of a conspecific in a lateral view with the eye displaced from the head to the tail, they again showed a significant preference for left-eye use. On the other hand, ‘eyeless’ conspecific model elicited no lateralized viewing in fry. Finally, the left-eye preference was revealed for scrutiny of the image of a conspecific eye alone. We argue that in Amur sleeper fry, eye is the element of the conspecific image, which can serve as a ‘key’ for the initiation of lateralized social response. This key element may serve as a trigger for the rapid recognition of conspecifics in the left eye–right hemisphere system. Possible causes and advantages of lateralized perception of social stimuli and their key elements are discussed in the context of current theories of brain lateralization.     

A new technique for measuring thermoregulatory behavior in the rat

A tracking procedure was used to investigate the ability of rats to regulate their ambient temperature. Rats were placed in a chamber with two levers; depressions of one lever controlled a cold-water flow (11 degrees C) and the other controlled the flow of hot water (57 +/- 1 degrees C). If it alternated responses, the rat could regulate temperature within these two extremes. With training, this regulatory behavior resulted in a narrow environmental temperature range that approximated normal body temperature.     

A method for eliciting scale errors in preschool classrooms

Six preschool classrooms, containing children between the ages of 4.0 and 40.0 months, were seeded with miniature items to examine how easily scale errors could be elicited. Observations occurred over a period of 3 months, with a total of 280 min of observations per classroom. A concealed observer documented all interactions with the miniature items. A total of 93 scale errors occurred, with a higher frequency committed by the younger children. These results confirm findings from previous research and suggest that scale errors can be effectively elicited in a preschool classroom. Our approach may provide a useful method for systematically studying the factors that influence scale errors.     

Uzilla: A new tool for Web usability testing

Web usability testing and research presents challenges for accurate data collection. An instrumented browser solution, Uzilla, is compared with existing solutions, and its contributions to usability testing practice are noted. Uzilla implements a client—server architecture based on the open source Mozilla browser. Instrumentation of the browser facilitates the evaluation of Web sites and applications inside and outside of the laboratory. An integrated data collection and analysis server application decreases the effort required to understand test results and facilitates iterative testing.     

A new probe technique for the identification of serial learning processes

We describe a new serial learning probe technique which permits identification of functional stimuli for each individual item immediately following the trial on which it has been learned. Some empirical evidence indicating the validity of the serial probe technique is also presented. The potential superiority of the probe technique over alternative experimental methods for determining the basic processes involved in serial learning is noted.     

A new technique for the assessment and modification of feigned memory deficit

The two-alternative forced-choice technique has been successful in the assessment of functional sensory deficits because it has the power to assess deception or exaggeration. This report describes how the procedure can be used for the assessment and modification of a memory complaint. Three case studies are presented. In two cases the supposed deficit was judged to be functional. In a third case a brain-injured patient "cheated" to obtain correct answers, suggesting that he was trying to hide a deficit and not attempting to obtain compensation.     

A runway for the fish

A runway and a training procedure arc described. Acquisition and extinction curves for a sample of 12 goldfish trained in spaced trials are plotted in terms of three measures.