In Favor of Laws that Are Not Ceteris Paribus After All

Opponents of ceteris paribus laws are apt to complain that the laws are vague and untestable. Indeed, claims to this effect are made by Earman, Roberts and Smith in this volume. I argue that these kinds of claims rely on too narrow a view about what kinds of concepts we can and do regularly use in successful sciences and on too optimistic a view about the extent of application of even our most successful non-ceteris paribus laws. When it comes to testing, we test ceteris paribus laws in exactly the same way that we test laws without the ceteris paribus antecedent. But at least when the ceteris paribus antecedent is there we have an explicit acknowledgment of important procedures we must take in the design of the experiments — i.e., procedures to control for “all interferences” even those we cannot identify under the concepts of any known theory. This revised version was published online in July 2006 with corrections to the Cover Date.     

Stress and dietary practices in adolescents.

Baseline data from the Health and Behavior in Teenagers Study (HABITS) were used to investigate associations between stress and dietary practices in a socioeconomically and ethnically diverse sample of 4,320 schoolchildren (mean age = 11.83 years). Male (n = 2,578) and female (n = 1,742) pupils completed questionnaire measures of stress and 4 aspects of dietary practice (fatty food intake, fruit and vegetable intake, snacking, and breakfast consumption) and also provided demographic and anthropometric data. Multivariate analyses revealed that greater stress was associated with more fatty food intake, less fruit and vegetable intake, more snacking, and a reduced likelihood of daily breakfast consumption. These effects were independent of individual (gender, weight) and social (socioeconomic status, ethnicity) factors. Stress may contribute to long-term disease risk by steering the diet in a more unhealthy direction.     

A note on a matrix criterion for unique colorability of a signed graph

A signed graph,S, is colorable if its point set can be partitioned into subsets such that all positive lines join points of the same subset and all negative lines join points of different subsets.S is uniquely colorable if there is only one such partition. Developed in this note is a new matrix, called thetype matrix ofS, which provides a classification of the way pairs of points are joined inS. Such a classification yields a criterion for colorability and unique colorability.The work reported here was supported by Grant MH 10834 from the National Institute of Mental Health.     

PERSONALITY CHANGE IN WOMEN PHYSICIANS FROM MEDICAL STUDENT YEARS TO MID-40S

Scales from the California Psychological Inventory's (CPI; Gough, 1987) Externality and Control clusters, in conjunction with a case study, were used to investigate personality change in a sample of women physicians who entered a Pacific Northwest medical school in 1964–1967. A core of 40 women was retested in their early 30s and mid-40s. From mid-20s to early 30s, the physicians'decreased scores on CPI's Sociability and Empathy scales indicated a greater internality. Decreases on the Responsibility and Good Impression scales indicated greater tendencies to question duties and obligations. An increase on the Achievement-via-Conformance scale indicated greater ability to achieve in structured situations. From early 30s to mid-40s, a further shift toward internality was evidenced by decreased scores on Social Presence and Self-Acceptance. Gains in leadership potential and increases on the Responsibility, Self-Control, Good Impression, and Achievement-via-Conformance scales were also noted.     

Forms, uses and functions of children's favourite objects

In this study, the notion of a favourite object is used as a heuristic concept for things that children are occupied with and absorbed by. According to earlier studies, favourite objects can be grouped into four categories: forerunners of transitional objects, primary and secondary transitional objects, and favourite toys. This initial classification was compared to results of cluster analyses of characteristics of favourite objects among 32 preschool and 30 primary school children, corroborating the initial classification and specifying the typology. The distribution of types of objects was different for the two groups of children, but was not dependent on age within groups or, for the preschool children, on mental development. These results indicate that changes of favourite objects with mental maturation are slow.
The softness of the material of primary and secondary transitional objects and the preference for objects that could be kept close to the body suggest that the comforting character of these favourite objects has its root in the child's self-soothing actions with the object.     

A note on some modifications of latent roots and vectors

When an arbitrary positive scalar matrix is added to a correlation matrix the latent roots of the sum are equal to the corresponding roots of the correlation matrix plus an amount equal to the scalar number of the scalar matrix. The latent vectors of the sum are identical with those of the correlation matrix. An approximation to these relationships is suggested for the case in which the sum is of a correlation matrix and of a positive semidefinite diagonal matrix. The approximation is used to allow the solution of a characteristic problem for a correlation matrix with unities in the main diagonal to provide a family of solutions for the same correlation matrix.This research has been supported by a grant from the National Institute of Mental Health, MH 7864-01.