Two basic methods exist for drawing probability samples to be used in telephone surveys: directory sampling (from alphabetical or street directories) and random digit dialing (RDD). RDD includes unlisted numbers, whereas directory sampling includes only listed numbers. The goal of this paper is to estimate the effect of failure to include…

A study was conducted at Los Angeles Pierce College (LAPC) to test the relative reliability of small-sample telephone interviewing and large-sample mailings with postcard and telephone reminders for student follow-up. The study involved conducting a telephone survey of 245 former students who had enrolled at LAPC in four program areas, and a mail…

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…

The utility of a quasi-experimental evaluation design for estimating benefits derived from a program to match job-seekers to openings listed by employers was examined in three studies of Job Service referrals and placements in Washington and Oregon. Data examined included a mail survey of a sample of 587 Washington residents referred to job…