Persuasion MAR 3503 February 7, 2012

A traditional model of persuasion

Untrustworthy sources can be persuasive! …When they are arguing against their own interests An experiment by Walster et al. (1966): Ps read about a convicted criminal, Joe “the Shoulder” Napolitano, who argues either for – More powerful, stricter courts – More lenient courts and sentences

Untrustworthy sources can be persuasive!

When is a disliked source persuasive? Again, when their messages are unexpected Ps read a message by a new university administrator who: – …Is likeable or unlikeable – …Delivers a desirable or undesirable message Eagly & Chaiken, 1975 Source is: Message is:LikeableUnlikeable Undesirable Desirable Amount of opinion change

Dual process theories System 1 (peripheral route): relatively fast, associative, based on simple heuristics, often automatic, requiring little cognitive capacity, often unconscious System 2 (central route): relatively slow, rule- based, operating on high-effort, systematic reasoning, requiring cognitive capacity, often conscious when operating Domains: judgment, decisions, attribution, person perception, stereotyping, persuasion

Elaboration Likelihood Model Two routes to persuasion: – Central route: when the target is motivated and able to systematically process the message – Peripheral route: when they are not The success of various source and message cues depends on which route a target is taking

Involvement and argument strength Ps read an essay arguing in favor of comprehensive exams, either – At their own school (high involvement) – At another school (low involvement) Arguments were either strong or weak Hypothesis: Argument strength should have a larger impact on attitudes under conditions of high involvement Petty & Cacioppo, 1979

Involvement and argument strength Petty & Cacioppo, 1979

Involvement and argument strength Argument strength: Issue involvementStrongWeak High Low Petty & Cacioppo, 1979 Data: agreement with author’s position

Mood and argument strength Ps are placed in a good mood or a bad mood by writing about happy or sad life events Then they read weak or strong arguments in favor of a tuition hike at their school Bless et al., 1990

Involvement, message, and source Issue: School should change to a trimester system, to be implemented either: – Next year (high involvement) – 10 years from now (low involvement) Source is either likeable and presents 1 argument or dislikeable and presents 5 arguments ELM makes unique predictions: Central route will lead to more change with dislikeable source, while peripheral route will lead to more change with likeable source Chaiken, 1980

Involvement, message, and source Source/message quality Dislikeable, 5 argumentsLikeable, 1 argument High involvement Low involvement Chaiken, 1980

Involvement, message, & expertise Comprehensive exams to be instituted: – Next year (high involvement) – 10 years from now (low involvement) Message contains 8 strong or 8 weak arguments Message is attributed to a high schooler (low expertise) or a Princeton professor (high expertise) Petty, Cacioppo, & Goldman, 1981

Involvement, message, & expertise Petty, Cacioppo, & Goldman, 1981 High personal relevanceLow personal relevance Attitude change

Celebrity endorsements Participants evaluate a magazine ad for a disposable razor High involvement: Product would soon be market tested in their community, and they would have an opportunity to select a razor as a free gift Low involvement: Product would soon be market tested in several distant cities Strong or weak arguments Endorsed by celebrities or random citizens Petty, Cacioppo, & Schumann, 1983

Celebrity endorsements Petty, Cacioppo, & Schumann, 1983

Celebrity endorsements Petty, Cacioppo, & Goldman, 1981 High personal relevanceLow personal relevance Attitude change

Message strength vs. # of arguments Comprehensive exams to be implemented in one year or 10 years (yes, again!) Number of arguments: 3 or 9 Argument strength: strong or weak Petty & Cacioppo, 1984

Message strength vs. # of arguments Low involvementHigh involvement Petty & Cacioppo, 1984 Attitude change

Message strength vs. composition Tuition hike, at one’s own school or a different school Three sets of arguments: – 3 strong arguments – 3 weak arguments – 3 strong and 3 weak arguments Petty & Cacioppo, 1984

Message strength vs. composition Petty & Cacioppo, 1984

When does attitude change endure? Attitudes formed via the central route: – Persist longer Watts (1977): Ps either write or read a persuasive essay. Attitudes are assessed immediately and 6 weeks later He found that writing and reading the essay produced the same amount of attitude change initially But writing the essay led to more processing via the central route, and thus more change 6 weeks later – Are more predictive of behavior Cornell housing study

Necessary psychological steps Perceive the message Favorably evaluate the message Understand the message Remember the message If any of these steps fails, information will be of no use

Perception

Favorable evaluation Why might people not favorably evaluate a helpful message? – The medium Not funny, interesting, likeable, fun – The message itself People get defensive when they’re being criticized – Sometimes people just don’t like things

Understanding Costanzo et al., 1986

Remember this Memory is not perfect Information may even backfire

Persuasion process

Summary Persuasion can happen through one of two routes: central and peripheral – Central route when people have motivation or ability to think about message – Peripheral when they do not What cues work to change attitudes differs depending on which route is in use – Peripheral cues include superficial aspects of endorsers and number of arguments – Central cues include argument strength and expertise, Central route attitude change is more likely to stick Next time: When do people comply with requests?