Models of Behaviour Change (e.g. TPB)

• What we do – our behaviour – is critical to our own lives, and also those of the people (and firms, and planet) around us. Consequently, many models have been built to predict when and how it will change.
  • We focus on one of the most famous, the Theory of Planned Behaviour (TPB)

The Theory of Planned Behaviour says that our intentions to act are shaped by 3 things:

• Attitude towards that thing – Do we like what we think it will do
  • This is shaped by beliefs we have about what its good and bad outcomes will be (e.g., it will make me attractive, or it will give me indigestion). We look at the handful of most salient such beliefs (usually about 2-4 of them)
  • Two judgments are made about each belief:
    • Our evaluation of how positive or negative it is
    • The strength of our belief – how likely we that this outcome will happen
  • For a given belief you get a score rating each of these factors, then multiply them together. Then you add these scores across  each of the relevant beliefs. The resulting number should reflect the attitude
  • These two factors suggest ways to change the attitude towards a behaviour. You pick relevant beliefs and then:
    • Change their positivity, by convincing the person that they will lead to better or worse outcomes
    • Change the strength of the belief. There are several ways of doing this, as beliefs are generally stronger when they are:
      • based on experience (vs. just being told about them)
      • self-generated (show don’t tell)
      • reinforced over time
• Subjective Norm towards the behaviour – Do we perceive reference groups as supportive or not supportive of the behaviour
  • This is shaped by two judgments about salient reference groups
    • The Norm strength – how positive or negative do we think this reference group’s influence is
    • Motivation to comply – how strongly do we want to be like or unlike this reference group
  • The math to combine them is the same as with attitudes
  • Marketers can try to influence norms by:
    • Social proof: expose people to information about people who like your product (or do the behaviour)
    • Provide reviews from other consumers: A special form of social proof
    • Use viral marketing to get people they already know (or are members of their tribe) to be seen using and liking the product
• Perceived Behavioural Control – do we feel like we are able to do the behaviour
  • This is shaped by two judgments about salient enablers / blockers
    • Control belief – do we feel that this factor makes it easier or harder to do the beahviour
    • Perceived power – does this factor affect us a little or a lot
  • The math to combine them is the same as with attitudes
  • Marketers actually do a lot to shape perceived control
    • Price is a big factor. Do people perceive the good as affordable?
    • Place is another one. Is the product available at the right time and place? Is it easy to navigate the shop or online buying and using environment?

We list several other related models, and discuss how they are similar and how they are different

• We also note that there is a very different type of model of behavioural change that looks at how people progress over time towards change
  • The Transtheoretic model describes six psychological stages people go to from having little awareness of the need to change, through to having completely absorbed the change, and not even thinking about their old ways of acting
  • The Diffusion of Innovations model has a number of facets, but one of those is about stages of acceptance that new innovations go through, from being picked up by a small number of early innovators, to finally being adopted by the last few laggards.