Persuasion and Attitude Change

This model states that there several factors that will affect how likely a change of attitude through persuasion is. The three most prominent factors are the source, the message and the audience.
Source
The Source Credibility theory states that people more likely to be persuaded when a source presents itself as credible, for example Bochner and Insko found that people were more likely to trust a sleep expert than a non-sleep expert, on matters surrounding sleep.
Message
The Hovland-Yale model says the content of the message is an important factor. O’Keefe’s meta-analysis of research on one-sided and two-sided messages found that two-sided messages influence attitudes more than one-sided messages. 
Audience
The audience strongly effects how likely someone is to be persuaded, McGuire found that more intelligent audiences are more likely to be persuaded by valid arguments because they have a longer attention span and can understand the arguments better. Too high or too low intelligent people are less easily influenced.

+ Real world application – It dealt with attitude change in practical ways and, indeed, much of the research is still relevant today and can be seen in advertising, speech writing and use by ‘spin doctors’  such as Alastair Campbell.

- Doesn’t explain how persuasion actually happens – Perhaps the greatest weakness of the Hovland-Yale approach is that it only really concentrates on the steps in the persuasion process, and doesn’t really offer an explanation of how persuasion actually occurs.

- Assumption that understanding a message leads to persuasion – The model assumes that attitude change always derives from an understanding of a message. This is obviously an important factor and probably the main reason behind persuasion and attitude change, but this does not guarantee that people are persuaded. For example, the Elaboration Likelihood model shows that persuasion can still occur even when a message is not fully understood or learned.

- Methodological issues – A lot of the research into persuasion and attitude measurement is faulty. For example, one of the main methods used is self-reports such as questionnaires, these can be unreliable and result in invalid date. 

Petty and Cacioppo suggested there are two different routes to effective persuasion, which  one is more effective will depend on whether the audience focus’ on the message itself, or outside factors, such as the credibility of the source; otherwise known as the central route and the peripheral route.

The central route to persuasion – This route is taken when the audience is more likely to focus on the content of the message, i.e. the strength of its arguments, than the context they are in. Because this route tends to be more measured and well-thought out than the peripheral route any attitude changes made in this way tend to be more lasting.

The peripheral route of persuasion – This route focuses on things surrounding the message, i.e. the attractiveness or credibility of the source, rather than the message itself. Fiske and Taylor said that this happens because we are ‘cognitive misers’ and will always look for the easiest route when making decisions, and this often means evaluation peripheral information rather than taking the time to evaluate the validity of the message. Attitude changes brought about through this route tend to be less personally important and less permanent.

Need for cognition – A ‘need for cognition’ means how much you think about something before making your judgement. Haugtvedt et al(1992) found that those with a high need for cognition tended to be more influenced by the central route of persuasion, and vice versa for low cognition and the peripheral route of persuasion.

Real-life application – Vidrine et al studied how the need for cognition can affect a smoking awareness campaign. She exposed students to either a fact (central route) or emotion based (peripheral route) smoking awareness campaign. Those with high need for cognition were more persuaded the fact based campaign and the participants with low need for cognition were more easily persuaded by the emotion based campaign. This suggests that the theory linking need for cognition and what route to persuasion is more effective is correct. This also shows a clear way in which the Elaboration-likelihood model can be useful in the real world, as advertising companies can tailor make their campaigns to suit varies levels of need for cognition.