Public service advertisements, disseminated via the mass media, have been credited with "positive attitudinal effects" in past research, but only certain kinds of such advertisements are really effective. Of the types of appeals used in television commercials--informative, emotional, "establishment" (or status quo), and fear--the establishment appeal had the least favorable effect on a test group of 248 sophomore college students. In fact, both the establishment and information-based appeals elicited decidedly negative attitudinal responses from those surveyed, although older, more socially secure, and female respondents tended to favor such appeals. Emotional appeals were most effective with all the respondents, even overcoming fatalism. The test results suggest the production of public service advertisements for specific subgroups of television viewers. (CH)