The effectiveness of humor in persuasion: The case of business ethics training

Although practitioners insist that humor is effective as an aid to persuasion, previous research has produced conflicting and inconclusive results. The thesis of this dissertation is that humor's effectiveness can be demonstrated only if it is first explained theoretically. After reviewing both humor theory and persuasion theory, specific propositions were made about when humor would be effective in persuasion. It was predicted that cartoon drawings would increase susceptibility to persuasion by generating an agreeable mood, that ironic comments would increase susceptibility to persuasion by providing a cognitive distraction, and that self-effacing humor would increase susceptibility to persuasion by increasing liking for the source.

The Ethics Challenge is a board game that uses cartoon characters and wisecracks to persuade Lockheed Martin employees to consult the ethics office when in doubt. Participants were 170 adults studying business at a large public university. The dependent variable was persuasion, measured with six behavioral intention items and five descriptive-adjective ratings. In a controlled experiment, elements of the humor were removed from the game. Whenever this inhibited the effectiveness of the Ethics Challenge, it was inferred that the element had been playing an important role.

Overall, the use of humor had a weak but significant impact on persuasiveness. Cartoon drawings alone generated negligible effects. Self-effacing humor improved the effectiveness of the message, seemingly by increasing source credibility. Ironic wisecracks improved the effectiveness of the message even more. Further research into the causal mechanisms that explain these results is advocated, and a campaign of reeducation is recommended to generate realistic expectations for the benefits of humor in the workplace.