This article demonstrates that the lower bound for the most deviant Z score and the upper bound for the sample standard deviation are attained simultaneously.

This article examines the statistical determinants of risk preference. In a meta-analysis of animal risk preference (foraging birds and insects), the coefficient of variation (CV), a measure of risk per unit of return, predicts choices far better than outcome variance, the risk measure of normative models. In a meta-analysis of human risk…

Background: Previous work has inconsistently reported difficulties with response reversal/extinction in children with psychopathic tendencies. Method: We tested the hypothesis that the degree of impairment seen in children with psychopathic tendencies is a function of the salience of contingency change. We investigated the performance of children…

Despite its intuitive appeal and popularity, Thorndike's constant ratio (CR) model for unbiased selection is inherently inconsistent in "n"-free selection. Satisfaction of the condition for unbiased selection, when formulated in terms of success/acceptance probabilities, usually precludes satisfaction by the converse probabilities of…

The multiple segment factorial vignette design (MSFV) combines elements of experimental designs and probability sampling with the inductive, exploratory approach of qualitative research. MSFVs allow researchers to investigate topics that may be hard to study because of ethical or logistical concerns. Participants are presented with short stories…

The authors introduce subset conjunction as a classification rule by which an acceptable alternative must satisfy some minimum number of criteria. The rule subsumes conjunctive and disjunctive decision strategies as special cases. Subset conjunction can be represented in a binary-response model, for example, in a logistic regression, using only…

The maximum and minimum of a sample from a probability distribution are extremely important random variables in many areas of psychological theory, methodology, and statistics. For instance, the behavior of the mean of the maximum or minimum processing time, as a function of the number of component random processing times ("n"), has been studied…

We present a theory of decision by sampling (DbS) in which, in contrast with traditional models, there are no underlying psychoeconomic scales. Instead, we assume that an attribute's subjective value is constructed from a series of binary, ordinal comparisons to a sample of attribute values drawn from memory and is its rank within the sample. We…

Prominent views of implicit priming agree that repetition of category exemplars should increase the probability of the exemplar coming to mind on a category production test. This prediction has been borne out in the data of numerous experiments that have used relatively high-frequency exemplars, but experiments that have used lower frequency…

In the high-probability request sequence (high-p) procedure, a requester presents a rapid sequence of requests a child is known to be likely to comply with, followed by a request to perform a response for which there is a low probability of compliance (low-p request). To extend previous research from institutional and research settings to home…

The concept of risk has entered into physics courses in various guises. It is treated explicitly in the "Advancing Physics" [1] course and implicitly at GCSE through "Ideas and Evidence" discussions. This could easily lead to such ideas as the balance between treatment and risk in radiotherapy and the likelihood of an asteroid strike. In this…

Accurate and accessible expressions for the probability of having a matching birthday are obtained by using Stirling's formula and Taylor series. For interest, the results are applied to the planets of our solar system.

A truncated version of the Cauchy distribution is introduced. Unlike the Cauchy distribution, this possesses finite moments of all orders and could therefore be a better model for certain practical situations. One such situation in finance is discussed. Explicit expressions for the moments of the truncated distribution are also derived.

The present series of 4 experiments investigated the probability of responding in accord with equivalence in adult human participants as a function of increasing or decreasing delays in a many-to-one (MTO) or comparison-as-node and one-to-many (OTM) or sample-as-node conditional discrimination procedure. In Experiment 1, 12 participants started…

We investigated the effects that sequences of reinforcers obtained from the same response key have on local preference in concurrent variable-interval schedules with pigeons as subjects. With an overall reinforcer rate of one every 27 s, on average, reinforcers were scheduled dependently, and the probability that a reinforcer would be arranged on…