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Want to make an impact? We have a 'likelihood' tip you can use.

Want to make an impact? We have a 'likelihood' tip you can use.

Whether you’re a behaviour change practitioner, involved in a behavioural insights unit, or even if you’re just someone trying to make a difference in your community, understanding human behaviour is often integral to creating positive change for your community and environment.

Subtle nudges to help people make better choices is hardly new, and the wider use of behavioural science to tackle societal issues has steadily grown in popularity in the last decade. Governments and industry are now increasingly using behavioural insights to address behaviour-focussed problems, from helping people put their waste in the correct bins to wearing masks during the pandemic to keep infection numbers to a low.

But when we consider the more complex and “wicked” problems we are currently facing, there are often tens, or even hundreds, of behaviours that need addressing.

Take for example: the problem of climate change. There are a myriad of climate mitigation and adaptation behaviours that could be addressed, but which of these behaviours should decision-makers prioritise to most effectively combat climate change?

Don’t make assumptions

It’s easy to make assumptions, use your intuition or anecdotal evidence to decide on which behaviour(s) to prioritise when designing an intervention or implementing a new policy. But for us at BehaviourWorks Australia, as behavioural scientists, we would much prefer to take a more evidence-focussed approach.

For over a decade, we’ve helped decision-makers from both government and industry tackle some of the world’s most pressing problems through a behavioural lens. Over the years, we have noticed a few common questions emerge among our project partners:

  • Which behaviours should be targeted to make an impact?
  • When, and to whom, should we target these behaviours?
  • How many behaviours should be targeted?

So, where do you start? And how do you find confidence in what you’re doing?

You make sure what you do is backed up by evidence.

That’s why we’ve developed an evidence-based approach to identifying and prioritising the most suitable behaviour(s) to address a problem: The Impact-Likelihood Matrix (ILM), developed by our very own Sarah Kneebone. By undertaking a rigorous investigation of the literature and audience research, our technique ensures that the behaviour(s) you choose to target for your intervention or policy will have the highest likelihood of driving the change you are seeking.

We’ve used this technique in a number of behavioural contexts for years, including water-saving behaviours, general waste behaviours, biodiversity behaviours and even food waste behaviours. This is how we did it:

Understanding water-saving behaviours for Aussie households

Australia’s urban population has been growing exponentially, and with this, there is an increasing need to secure sustainable urban domestic water supplies. Looking at it from a behavioural perspective, we conducted an investigation to find the most effective behaviours to target in interventions aiming to reduce water use in households.

To map out and prioritise these behaviours, we used the ILM. The tool allows practitioners to visualise behaviour prioritisation by plotting each behaviour and its impact on the issue against its likelihood of adoption by its audiences onto a matrix.

This process makes it easy for practitioners to see which behaviours could be considered as the ‘low-hanging fruit’ or ‘quick wins’ (behaviours that are highly impactful and easy to perform by audiences), the ‘shoot for the moons’ (behaviours that are highly impactful, but may take longer to adopt amongst its audiences and may require systems change), and behaviours not worth addressing at all.

Fig. 1: Prioritisation matrix produced from what behaviours industries perceive have an impact (Y-axis) and what behaviours Australian households perceive are adoptable (X-axis). (Taken from Kneebone et al., 2017).

In our investigation to understand water-saving behaviours in Australian households, we first categorised the behaviours into ‘types’ (such as ‘efficiency’, ‘curtailment’, and ‘maintenance’ behaviours) before mapping them onto an ILM. This extra step helped us identify which behaviour ‘types’ would be most effective to target in program-based interventions, which could be useful for policymakers seeking large-scale change.

Identifying behaviours to drive a circular economy

We’ve utilised the ILM tool on a range of  our projects and programs with government and industry partners as well. As part of our Waste & Circular Economy Collaboration, a nation-wide collaborative program with our Consortium Partners, we’ve developed the first holistic comparison of Circular Economy behaviours targeted by Australian government programs for households. This gave program designers and other key decision-makers the critical information needed to design campaigns that are most effective in reducing the generation of waste in Australian households.
Findings from the behavioural research have since been further developed to inform projects and programs that have leveraged off these initial findings, particularly in regards waste avoidance behaviours.

Making a positive impact on biodiversity through behaviour change

With conservationists increasingly seeking effective ways to reduce society’s impact on biodiversity, we looked into identifying and prioritising effective human behaviours that benefit biodiversity.

Fig. 2: Prioritisation matrix for biodiversity behaviours that a typical Victorian individual could undertake. (Taken from Selinske et al., 2020).

The Victorian-based project prioritised the 10 most effective behaviours determined by their likely impact(s) on biodiversity conservation and current prevalence in the state, identified out of the initial list of 27 behaviours. It aimed to provide a first step for Victorian decision-makers to make changes that will increase society’s positive impact on biodiversity, guide individuals to reduce their own biodiversity footprint, and more broadly, develop a behaviour change research agenda for behaviours most likely to benefit biodiversity.

Campaigning against food waste

Identifying and prioritising behaviours also offer practitioners an effective method of simplifying ‘the message’ to appeal to public audiences.

Committed to tackling food waste, OzHarvest reached out to our team to identify the behaviours that matter most in reducing food waste in Aussie households. Our investigation identified 36 initial behaviours, which we later short-listed to highlight the top 6 best ‘evidence-based’ behaviours by using the ILM.

These findings came to inform OzHarvest’s Use-It-Up campaign to reduce food waste in Australian homes. The campaign, with its simple messaging of using food up, has since garnered far-reaching media attention across the country and continues to gather momentum.

So, to wrap it all up…

In short, it’s important to know which behaviours to prioritise when seeking to change behaviour to combat some of our more wicked problems. Using a tool, such as the ILM, which is our evidence-based approach to prioritising behaviours, is a good place to start to ensure the behaviours you choose to target will have the highest likelihood of effectiveness in achieving your policy or intervention goals… and could potentially help in an intervention’s strategy development as well. If you skip this process, you could risk wasting time and resources committing to behaviours that have a very small impact on the problem and/or are ones that would have never been widely adopted by its target audience.

If you’re wondering where to start in choosing the right behaviours to target, need a little help in conducting an ILM, or even just wanting to learn more about the process, get in touch with us at behaviourworksaustralia@monash.edu. We also offer a suite of professional development courses that could help you in kickstarting your behaviour change project.  

Get in touch with us to partner on your project.

Authored by Malaika Jaovisidha

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