Elliot M. Cramer

Recollection of childhood events in adults with irritable bowel syndrome

We examined retrospectively premorbid factors that might relate to the development of irritable bowel syndrome (IBS). We administered a semistructural interview to adult IBS patients, adults with symptoms of IBS who had not visited a doctor (nonpatients), and asymptomatic normals. Patients with IBS differed from nonpatients by reporting more severe bowel problems, more frequent doctor visits in childhood, and more pain associated with current bowel symptoms. These factors may contribute to the tendency of people with bowel symptoms to seek medical care. More patients, and in most cases nonpatients with IBS, reported poorer general health and headaches, stomachaches, and bowel complaints during childhood. They also showed evidence for greater parental attention to illness with more frequent school absences and doctor visits than normal subjects. Loss and separation during childhood, and in the current family, and conflicted or dependent maternal relationships were also more frequently reported among patients and nonpatients. These factors may contribute to the development of IBS.

Some symmetric, invariant measures of multivariate association

A distinction is drawn between redundancy measurement and the measurement of multivariate association for two sets of variables. Several measures of multivariate association between two sets of variables are examined. It is shown that all of these measures are generalizations of the (univariate) squared-multiple correlation; all are functions of the canonical correlations, and all are invariant under linear transformations of the original sets of variables. It is further shown that the measures can be considered to be symmetric and are strictly ordered for any two sets of observed variables. It is suggested that measures of multivariate relationship may be used to generalize the concept of test reliability to the case of vector random variables.

Some Results Relevant to Choice of Sum and Sum-of-Product Algorithms

Sum and sum-of-product algorithms, some designed to minimize significance error, are compared and recommendations for usage are offered. A simplified method of rounding is presented and the benefit of using it demonstrated. Results are presented for the IBM 360 as well as the IBM 7040 computers with obvious application to some other machines.

Recent Research (N = 9,305) Underscores the Importance of Using Age-Stratified Actuarial Tables in Sex Offender Risk Assessments

A useful understanding of the relationship between age, actuarial scores, and sexual recidivism can be obtained by comparing the entries in equivalent cells from “agestratified” actuarial tables. This article reports the compilation of the first multisample age-stratified table of sexual recidivism rates, referred to as the “multisample age-stratified table of sexual recidivism rates (MATS-1),” from recent research on Static-99 and another actuarial known as the Automated Sexual Recidivism Scale. The MATS-1 validates the “age invariance effect” that the risk of sexual recidivism declines with advancing age and shows that age-restricted tables underestimate risk for younger offenders and overestimate risk for older offenders. Based on data from more than 9,000 sex offenders, our conclusion is that evaluators should report recidivism estimates from age-stratified tables when they are assessing sexual recidivism risk, particularly when evaluating the aging sex offender.

Balancing - Analysis of Variance by Another Name:

In Report 7 (1971) of the National Assessment of Educational Progress, an analytic technique known as balancing was introduced. The stated purpose of this technique is the elimination of confounding in multifactor survey studies in which some attributes are not equally represented in all cells of the survey sample design. The likely impact of the NAEP reports is great, and it is vital that the nature of the analyses and their relationships to other known analytic techniques be clearly understood. This report shows that the estimation procedure used in balancing is the equivalent of that employed in the nonorthogonal analysis of variance in an additive model. The nature of weighting schemes for the definition of marginal populations is considered in detail as well as the implications of these various schemes to interpretation of results. The results on weighting schemes and interpretations apply to both balancing and a much broader class of analyses.

A Nonorthogonal Analysis of Variance Program

Abstract A general computer program for univariate and multivariate nonorthogonal analysis of variance is described. Its use is illustrated with a two-factor problem with missing cells. It is pointed out that the criticisms of Francis regarding this program are unwarranted.

Comparison of the accuracies of some regression algorithms

Cholesky factorization and Householder orthogonalization procedures are discussed with respect to accuracy of error terms for regression models. Error formulas corresponding to sample sums of squares are related to known results to illustrate the superior accuracy of the Householder method. A stepwise Householder procedure is discussed and its corresponding error term derived. In consideration of accuracy, speed and storage requirements the stepwise Householder procedure is recommended as the most suitable compromise