Fecundability and the Frequency of Marital Intercourse: New Models Incorporating the Ageing of Gametes

A companion paper in the last issue reviewed the literature on effects of frequency of intercourse on fecundability. At moderately high coital frequencies, predicted effects of further increases on fecundability based on previous work vary widely. New modelling reported here, designed to take into account the ageing of gametes, attempts to identify a set of limits within which the true relationship of coital frequency and fecundability at moderate to high frequencies may confidently be expected to lie.     

Updating discriminant functions estimated from inverse gaussian populations

The problem of updating discriminant functions estimated from inverse Gaussian populations is investigated in situations when the additional observations are mixed (unclassified) or classified. In each case two types of discriminant functions, linear and quadratic, are considered. Using simulation experiments the performance of the updating procedures is evaluated by means of relative efficiencies.     

Asymptotic non-null distribution of a test of equality of exponential populations

In this paper further asymptotic expansions of the non-null distribution of the likelihood ratio criterion for testing the equality of several one parameter exponential distributions are obtained when the alternatives are close to the hypothesis. These expansions are obtained for the first time in terms of beta distributions.     

Regression from another angle

This paper presents a simply viewed framework that brings together various concepts of regression, prediction, and principal components. Several new concepts related to prediction are introduced, and then the interrelationships of these concepts are established. The generalizations are examined in detail and are illustrated in the context of a well known data set.     

Laws,Desires, and Contaminations—Mutuality with a Price: Commentary on Paper by Taras Babiak

In this commentary on Tara Babiak's analytic work with a very disturbed, almost autistic young man, I take up the function of gender categories as defense and as potential; the power of enactments in analytic treatment; and the difficulties of homophobia in patient, analyst and culture. I focus on the uses and functions of gender and ideals of masculinity in the patient's identity. A central enactment early in the treatment gave rise to intense transference and countertransference scrutiny. I suggest the long shadow cast by this enactment, which was both hopeful and provocatively destructive. I discuss the quandaries (analytic, personal, and cultural) for the analyst working with a patient for whom phobic dread may be a defense against fragmentation and madness.     

Evaluation of the parameters of su by rational fractions

A rational fraction approximation is given for a function of one of the parameters defining Johnson's S_UError assessment for a segment of the domain of validity shows remarkable accuracy.