Halfway technologies

An extraordinary gamut of medical and surgical therapies could be considered "halfway technologies," addressing mere symptoms or manifestations of disease, rather than the underlying pathogenesis. When a "halfway" technology is also lifesaving, its value cannot be underestimated by the individual patient. The example of organ transplantation explored in this column represents a halfway technology. It does not treat the underlying disease itself, but reflects the absolute failure of all efforts at medical and conservative therapy and is a last ditch, gerry-rigged lifesaving solution. And what about "quarter technologies"--the bridge to transplant devices--designed to get the patient halfway to the final halfway procedure?     

Fighting back: Vulnerabilities,blunders, and countermobilization by the targets in three animal rights campaigns

Among the determinants of social movement success, the characteristics and responses of nonstate organizations under attack by protestors have been overlooked. We examine three campaigns by animal rights groups against experimentation, in 1976–1977, 1987–1988, and 1988–1989. The first two campaigns stopped the research, while the third did not. One influential set of factors was the preexisting vulnerabilities—e.g., unpopular practices, internal factions—on the part of targeted organizations. Another was the strategic responses of these organizations, especially the avoidance of blunders. A growing countermovement, thirdly, affected the organizations' ability to respond effectively and avoid blunders. As a social movement expands and strengthens, it encourages counterorganizing and a hardening of resistance, so that many social movements may actually be less successful as they become larger and more visible.Revised version of a paper presented at the annual meeting of the American Sociological Association, Washington, DC, August 1990.     

Knowledge gap effects in a health information campaign

The evaluation of a campaign to increase cardiovascular health knowledge indicates that within the treatment community, education was a significant predictor of knowledge before the campaign but was not a significant predictor after the campaign. Two variables related to motivation to acquire information about cardiovascular health (age and perceived threat of heart attack) were not significant predictors of knowledge before the campaign but were significant predictors afterwards. These results suggest that the infusion of information into a social system via the mass media can close as well as open knowledge gaps and that motivation to acquire information in a specific knowledge domain is a factor controlling gap effects.     

Dropouts and continuers in Gamblers Anonymous: Part four. Evaluation and summary

In this fourth part of a study of dropouts from Gamblers Anonymous, the design, aims and rationale of which are outlined in part 1 (Brown, 1985b) experiences of GA by a sample of dropouts who had attended more than one meeting are analyzed and compared with similarly obtained responses from a group of continuing attenders who had not gambled for at least one year. The overall pattern of findings from the three prior parts of the study is interpreted as suggesting that

1. Gamblers anonymous may be better at coping with those whose gambling has been severely excessive and had led to many problems. However GA's approach is not so easily accepted and therefore not so effective with those who seek help at an earlier stage in the development of their problems.
2. Gamblers Anonymous may work better with those who have few relapses or best with those who have none at all. Although it may be very helpful in avoiding relapses, it may be less helpful in dealing with them when they do occur.

problems of the representativeness of the sample, of generalizing to Gamblers Anonymous as a whole, and of arguing from associations to causes are discussed. A general picture of the organization as a whole is presented.     

Multivariate Bayesian variable selection and prediction

The multivariate regression model is considered with p regressors. A latent vector with p binary entries serves to identify one of two types of regression coefficients: those close to 0 and those not. Specializing our general distributional setting to the linear model with Gaussian errors and using natural conjugate prior distributions, we derive the marginal posterior distribution of the binary latent vector. Fast algorithms aid its direct computation, and in high dimensions these are supplemented by a Markov chain Monte Carlo approach to sampling from the known posterior distribution. Problems with hundreds of regressor variables become quite feasible. We give a simple method of assigning the hyperparameters of the prior distribution. The posterior predictive distribution is derived and the approach illustrated on compositional analysis of data involving three sugars with 160 near infrared absorbances as regressors.     

Summary measurements and screening in clinical trials with replicate observations

Repeating measurements of efficacy variables in clinical trials may be desirable when the measurement may be affected by ambient conditions. When such measurements are repeated at baseline and at the end of therapy, statistical questions relate to: (1) the best summary measurement to use for a subject when there is a possibility that some observations are contaminated and have increased variances; and (2) the effect of screening procedures which exclude outliers based on within- and between-subject contamination tests. We study these issues in two stages, each using a different set of models. The first stage deals only with the choice of the summary measure. The simulation results show that in some cases of contamination, the power achieved by the tests based on the median exceeds that achieved by the tests based on the mean of the replicates. However, even when we use the median, there are cases when contamination leads to a considerable loss in power. The combined issue of the best summary measurement and the effect of screening is studied in the second stage. The tests use either the observed data or the data after screening for outliers. The simulation results demonstrate that the power depends on the screening procedure as well as on the test statistic used in the study. We found that for the extent and magnitude of contamination considered, within-subject screening has a minimal effect on the power of the tests when there are at least three replicates; as a result, we found no advantage in the use of screening procedures for within-subject contamination. On the other hand, the use of a between-subject screening for outliers increases the power of the test procedures. However, even with the use of screening procedures, heterogeneity of variances can greatly reduce the power of the study.     

Screening opportunity bias in case-control studies of cancer screening

In case-control evaluations of cancer screening, subjects who have died from the cancer in question (cases) are compared with those who have not (controls) with respect to screening histories. This method is subject to a rather subtle bias, among others, whereby the cases have greater opportunity to have been screened than the controls. In this paper, we propose a method of correction for this bias. We demonstrate its use on two case-control studies of mammographic screening for breast cancer.     

An Interview with Ben Brown,Co-founder of So New Media and Publisher of Words! Words! Words!

Abstract

With this installment of “They Might Be Giants,” Michael Brown talks with Ben Brown (no relation) about publishing books (ten so far!) and magazines (issue 3 of Words! Words! Words! is about to be released), while at the same time working nine-to-five at a really boring tech job. It's a do-it-yourselfer's dream come true. Serials Review 2002; 28:344–348.     

Local influence regression diagnostics for gamma data

The local influence diagnostics proposed in general terms irl Cook (1986), Thomas and Cook (1989) and Billor and Loynes (1993). arc adapted for gamma data. A data set prcviously analysed using different methods is then reexamined, and conclusions based on wing the new approach are made.