Risks of life on the street caused by inclement weather, harassment, and assault threaten the unsheltered homeless population. We address some challenges of enumerating the street homeless population by testing a novel capture-recapture (CR) estimation approach that models individuals' intermittent daytime visibility. We tested walking and…

Selectivity problems are discussed in terms of a general model that is estimated by the maximum likelihood method. Both single-group and multiple-group analyses are considered. An extension of the general model to latent variable models is discussed. (Author/PN)

Reliability and validity of self-report data provided by 178 mentally ill homeless persons were generally favorable. Self-reports of service use also generally agreed with treatment staff estimates, providing further validity evidence. Researchers and administrators can be relatively confident in using such data. (SLD)

Prediction of success in a special program often guides program participant selection and treatment. If the statistical analysis used to develop such predictions is based on the special selectivity built into the program, the predictions can be misleading and the validation tests uninformative. Federal district court pretrial release data is used…

This article presents a synopsis of each of seven presentations given at a conference on design and analysis in community trial studies. Papers identify problems with community trials and discuss strengths and weaknesses associated with design and analysis strategies. Areas of consensus are summarized. (SLD)

Electricity conservation programs were implemented in matched pairs of office-classroom-laboratory buildings and dormitories. The methodological problems of predicting consumption levels, interpreting why changes in consumption occurred, and estimating initial waste levels are discussed along with their implications for the conduct of behavioral…

Tracking and two statistical methods (probability weighting and sample selection modeling) were studied as ways to minimize bias attributable to sample attrition in school-based studies. Data on student smoking from 30 middle schools illustrate that sample weighting yields the best results, with estimates superior to sample selection and much less…

Evidence is presented that strengthens the argument against comparison group research strategies. Results from a study of youth attitudes related to the California Conservation Corps involving 528 participants and 668 comparisons indicate that the comparison group may not adequately represent the nontreatment state. (SLD)

A beverage-server intervention project at two West Coast Navy bases that attempted to reduce levels of alcoholic intoxication via policy changes and server training is described. Data obtained via interviews and structured observations of 1,511 club customers indicate methodological bias and self-selection effects. Bias adjustments were performed…