LOTTERIES AND THE TIME HORIZON

Abstract— People chose between hypothetical alternatives of (a) a million-dollar lottery prize and (b) a much smaller but certain amount of money When probabilities of winning the lottery were above about 1/100,000, subjects avoided risk, for example, a 1/100,000 probability of the million-dollar prize was chosen about as often as $700 for sure But at probabilities below 1/100,000, subjects sought risk, for example, a 1/1,000,000 probability of the million-dollar prize was chosen about as often as $9 for sure This crossover from risk aversion to risk seeking is predicted by Mazur's (1987) hyperbolic delay discount function with probability expressed as average delay due to strings of losses followed by a win, together with a time horizon limiting subjective delay     

An empirical investigation of adolescent suicidal ideation.

Four hundred nine high school students were surveyed to determine the percentage who had experienced suicidal ideation. The sample was then divided into high- and low-suicidal-risk groups. High-risk subjects were found to have significantly poorer quality friendships, lower self-esteem, and had experienced more life stress in the previous year.     

Stimulus range,number of categories,and the “virtual” exponent

Three different stimulus modalities (line length, number, and sound pressure) were judged by magnitude scaling techniques and by 7-, 15-, 31-, and 75-point category scales. All of the 40 subjects were given the same number stimuli, but two different sound-pressure ranges were presented (each to 20 subjects) and four different line-length ranges were presented (each to 10 subjects). Analyses of lack of fit for various simple functions were performed to determine bestfitting functions. The simple power function was often found to be an adequate fit to the data for all the response modalities used, although all of the response modalities were sensitive to changes in stimulus range. For simple power functions, the category-scale exponent was a function of both the range of stimuli and the number of categories provided. Category scales did not always produce exponents smaller than those obtained with magnitude estimation, which calls into question the concept of a virtual exponent for category scales.     

Moralist,technician, sophist,teacher/learner: Reflections on the ethicist in the clinical setting

The ethicist's role in the clinical context is not presently well defined. Ethicists can be thought of as moralists, technicians, Sophists, or as teachers and learners. Each of these roles is examined in turn. An argument is made for the ethicist as a teacher who must also learn a great deal about the clinical setting in order to encourage an effective critical examination of basic values. Four specific tasks of this teaching role are discussed: describing moral experience, eliciting assumptions, considering multiple alternatives and justifying choices.     

Perceived trustworthiness of knowledge sources: the moderating impact of relationship length

Prior meta-analytic evidence has indicated no association between relationship length and perceived trustworthiness. Viewing trustors as information processors, the authors propose a model in which relationship length, although having no direct effect on perceived trustworthiness, moderates the association between perceived trustworthiness and the basis on which people decide to trust each other. Specifically, as trustors learn about others, they base their trust on different kinds of information (demographic similarity, trustworthy behavior, and shared perspective). Hierarchical multiple regression analyses of a field survey of supervisors and subordinates from 3 companies (N = 88) provide evidence consistent with this prediction: Perceived trustworthiness is associated with demographic similarity in newer relationships, with trustworthy behavior in relationships that are neither brand new nor old but in-between, and with shared perspective in older relationships.     

A signal detection analysis of the rod and frame test

To help determine hut what Witkin’s Rod and Frame Test measures, the task was modified by presenting the luminous rod in one of two fixed positions, either vertical or not vertical, within a titled frame. S responded on a four-category scale representing his certainty that the rod was vertical Receiver operating characteristic (ROC) curves were calculated for each of 17 Ss and compared to traditional measures of titer field dependence-independence. The results showed that Witkin’s test is not contaminated to any great extent by response bias. However, the ROC analysis did reveal significant differences between field dependents and independents, not only in their sensitivity to verticality, but also in their- characteristic manner of responding.     

On the discriminative control of concurrent responses: the relations among response frequency, latency, and topography in auditory generalization

Human subjects were used in a study of auditory generalization following multiple-response discrimination training. The relations observed among stimulus intensity, response probability, and response latency were invariant with respect to whether the two vocal responses conditioned were topographically discrete, as in one experiment, or topographically continuous, as in another. The major findings were:

1. The probabilities associated with a specific response were maximal over several stimulus values at the extreme ends of the continuum, then dropped sharply at stimuli intermediate to the initial S^D's as the probability of the alternative response increased.

2. Overall response latency was inversely related to the relative frequency of the two responses at each stimulus value. When the two responses were most nearly equal in probability, latencies were maximal; when one response had close to unit or zero probability, latencies were minimal.

3. Analysis of the latencies of the two responses, taken separately, revealed: (a) an increase in latency as the difference between the test stimulus and the initial S^D increased; (b) a sharp discontinuity in the latency gradient and reversal in trend at intermediate stimulus intensities; and (c) at a given stimulus value, latencies associated with the stochastically dominant response were consistently shorter than those of the nondominant response.

4. No changes in response topography (fundamental frequency) were correlated with the characteristic changes in probability and latency during stimulus generalization.