A simple multivariate probabilistic model for preferential and triadic choices

Multidimensional probabilistic models of behavior following similarity and choice judgements have proven to be useful in representing multidimensional percepts in Euclidean and non-Euclidean spaces. With few exceptions, these models are generally computationally intense because they often require numerical work with multiple integrals. This paper focuses attention on a particularly general triad and preferential choice model previously requiring the numerical evaluation of a 2n-fold integral, wheren is the number of elements in the vectors representing the psychological magnitudes. Transforming this model to an indefinite quadratic form leads to a single integral. The significance of this form to multidimensional scaling and computational efficiency is discussed.The authors would like to thank Jean-Claude Falmagne and Norman Johnson for suggestions and advice concerning quadratic forms.     

Risk aversion and elite-group ignorance

Critical race theorists and standpoint epistemologists argue that agents who are members of dominant social groups are often in a state of ignorance about the extent of their social dominance, where this ignorance is explained by these agents' membership in a socially dominant group (e.g., Mills 2007). To illustrate this claim bluntly, it is argued: 1) that many white men do not know the extent of their social dominance, 2) that they remain ignorant as to the extent of their dominant social position even where this information is freely attainable, and 3) that this ignorance is due in part to the fact that they are white men. We argue that on Buchak's (2010, 2013) model of risk averse instrumental rationality, ignorance of one's privileges can be rational. This argument yields a new account of elite-group ignorance, why it may occur, and how it might be alleviated.     

A Thurstonian model for the dual pair (4IAX) discrimination method

The Institute for Perception, Richmond, Virginia In the dual pair method, the subject is presented with two stimuli in two pairs: One pair is composed of two samples of the same stimulus; the other pair is composed of two samples of different stimuli, one being the same as that in the identical pair. The task of the judge is to select the most different pair. The psychometric function for the dual pair method is derived and expressed in terms of a singly noncentral beta distribution. A table is provided that connects a measure of the degree of difference, d , to the probability of a correct response. This table assumes an unbiased observer and differencing decision rule. A table is provided to give an estimate of the variance of d¢, the experimental estimate of d. The power of the dual pair method is also investigated, and a formula to determine the sample size required to meet Type I and Type II error specifications is given. The dual pair method appears to be slightly less powerful than the duotrio and the triangular methods. Experimental investigation is needed to explore the dual pair in applied research work.     

Trends in Online Academic Publishing

Modern information technology allows academics many new ways to enhance their research activities. This article suggests that one of the most important changes in recent years has been the overwhelming proliferation of academic research. It proposes that many new developments in online publishing have been, and will continue to be, in response to this proliferation of research. It also offers some general principles based on six years' working for a series of innovative online journals, including examples of where new technologies have been used successfully to enrich a journal's content without adding substantively to the workloads of authors and editors.     

Supportive Distortions: An Analysis of Posts on a Pedophile Internet Message Board

A covert observation of posts on a pro‐pedophile Internet message board investigated evidence of distorted cognitions that were supportive of sexually abusive behavior. Implications for the treatment and supervision of members of online communities that support pedophilic interests and behaviors are discussed.     

Can Facilitation Imagery Alter the Effects of Semantic Priming?

This study examined if task motivational imagery suggestions could facilitate a semantic priming effect, relative to general relaxation suggestions and no specific suggestions; and if the participants’ hypnotizablity moderated the effects of the three types of instructions. Participants (n = 127) were assigned randomly in groups to one of the three instructional conditions (imagery, relaxation, or control) and two versions of a stimulus list for counterbalancing. A 3-way analysis of variance suggested that the semantic priming effect was found to be stronger for stimulus list version 2 than for version 1. A stronger semantic priming effect was found for the high, relative to the low and medium, hypnotizable groups. When medium hypnotizable participants were excluded, an instructional group X hypnotizability group interaction was found for list 1 suggesting that while the low hypnotizable participants benefited more from the relaxation suggestion, the high hypnotizables benefited more from the imagery instruction. The results suggest that imagery instructions may moderate automatic processes for highly hypnotizable individuals.     

The role of awakening cortisol and psychological distress in diurnal variations in affect: a day reconstruction study

People often feel unhappy in the morning but better later in the day, and this pattern may be amplified in the distressed. Past work suggests that one function of cortisol is to energize people in the morning. In a study of 174 students, we tested to see whether daily affect patterns, psychological distress, and awakening cortisol levels were interlinked. Affect levels were assessed using the Day Reconstruction Method and psychological distress was measured using the Depression Anxiety Stress Scales. On average, positive affect increased markedly in a linear pattern across the day, whereas negative affect decreased linearly. For the highly distressed, this pattern was stronger for positive affect. Lower than average morning cortisol, as assessed by two saliva samples at waking and two samples 30 min after waking, predicted a clear increasing pattern of positive affect throughout the day. When we examined the interlinkages between affect patterns, distress, and cortisol, our results showed that a pronounced linear increase in positive affect from morning through to evening occurred chiefly among distressed people with below average cortisol levels upon awakening. Psychological distress, although not strongly associated with morning cortisol levels, does appear to interact with cortisol levels to profoundly influence affect.