Tables of d′ for variable-standard discrimination paradigms

Signal detection theory (SDT) allows a bias-free measure of sensitivity, d′, to be simply estimated from discrimination data when certain conditions are met. The computation is not straightforward, however, in several popular discrimination designs, such as two- and four-interval same-different designs and the ABX design. The present tables, derived from the SDT models of Macmillan, Kaplan, and Creelman (1977), make possible the estimation of d’ from these complex discrimination designs.     

Effect of effort and latent extinction on resistance to extinction

Sixty-four male Wistar rats were given acquisition training in an enclosed straight-alley runway which could be adjusted for angles of inclination. The 2×2×2 design involved two angles of inclination in acquisition (0° and 40°) and two angles of inclination in extinction (0° and 40°). Between acquisition and extinction, half the subjects were exposed to a latent extinction procedure and half served as controls. Number of responses in a 30-min extinction session was an inverse function of effort required in extinction. Additionally, latent extinction procedures resulted in reduced resistance to extinction, but only when the effort conditions of acquisition and extinction were constant. When the effort conditions of acquisition and extinction were dissimilar, latent extinction procedures resulted in increased resistance to extinction. The results raise questions about the nature of the learning which occurs during latent extinction training.     

Intracranial cannulation of small animals

Special difficulties are encountered when attempting to provide intracranial cannulation of small animals that have floating or fragile skull bones. The technique described was developed for mice but seems applicable to other species. The cannula system is inexpensive and easy to use. A wound clip anchor seems superior to either skull screws or bonded acrylic, producing less damage to the brain and no necrosis of bone or tissue on the wound margin. Patency data up to 25 days is presented, and the system is as efficacious as other techniques.     

Psychological adjustment in transvestism and transsexualism

Thirty-four transvestites who had shown fetishistic arousal in association with cross-dressing were categorized into two groups on the intensity of feminine gender identity. The two transvestite groups were compared to a group of 24 non-fetishistic transsexuals who sought a full sex change operation. Ss in all three groups reported greater current psychological stress and scored higher on neuroticism and introversion than Ss in a normal population. A large proportion of Ss in the three groups had previously sought psychiatric help. The degree of psychological maladjustment was not related to the intensity of feminine gender identity.     

Four pathways to young-adult smoking status: adolescent social-psychological antecedents in a midwestern community sample.

Evaluated the ability of social-psychological factors, measured in adolescence, to predict young-adult smoking outcomes. Results showed substantial continuity in the antecedents of adolescent and young-adult smoking but important discontinuities as well. Beliefs in the negative social consequences of smoking and beliefs about academic success and independence were important to adolescent but not to adult smoking. Conversely, beliefs in the negative health consequences of smoking were more important to adult smoking than to adolescent smoking. Results also showed an appreciable amount of smoking onset after the high school years, as well as an appreciable amount of adolescent smoking that did not persist into young adulthood. Antecedents of late-onset smoking and of nonpersistent smoking are described.     

An ethics of suffering: does it solve the problems we want to solve?: commentary

Erich H. Loewy proposes to elevate the moral obligation to prevent and relieve suffering to the level of a prima facie moral duty by delineating which beings are of primary moral worth and which are of secondary moral worth. Sentient beings have a capacity to suffer and are therefore of primary moral worth. Beings that are insentient cannot suffer; therefore such beings are only of secondary moral worth. Objects of secondary moral worth include patients in a persistent vegetative state (PVS) and brain-dead patients. This proposal, he says, would solve a number of problems in clinical bioethics. First, it would help to clarify our moral duties at the bedside. And secondly, by creating a hierarchy of moral values, it helps to differentiate which patients are owed our primary allegiance and resources. Despite his extensive and painstaking proof, I believe several questions remain about the use of the "capacity of sentient beings to suffer" as a basis for a universal grounding in ethics.     

The polyserial correlation coefficient

The polyserial and point polyserial correlations are discussed as generalizations of the biserial and point biserial correlations. The relationship between the polyserial and point polyserial correlation is derived. The maximum likelihood estimator of the polyserial correlation is compared with a two-step estimator and with a computationally convenient ad hoc estimator. All three estimators perform reasonably well in a Monte Carlo simulation. Some practical applications of the polyserial correlation are described.By coincidence, the first author and the second and third authors learned that they were working independently on closely related problems and, consequently, decided to write a jointly authored paper.