Behavioural Economics vs. Behaviour Change vs. Behavioural Science - what's the difference?
Updated: Dec 13, 2022
I've been working as a behavioural science practitioner for a decade now and I often come across misunderstandings about the difference between behavioural economics, behaviour change and behavioural science in general. After a recent discussion with a client, I wanted to write about this to help people understand some of the differences and talk about what it means for my professional practice.
Before I start, I want to emphasise I'm deliberately using "broad brush strokes" to establish the bigger picture - some of the terminology is relatively fuzzy and there is overlap between disciplines. Human behaviour is multiply determined and the science of understanding it is complex!
What is behavioural economics?
What most people know as behavioural economics actually falls under the broad umbrella of judgment and decision making psychology. BE as a term has different definitions and until relatively recently didn't exist as a discipline, even though the research often cited as behavioural economics goes back 50-60 years. The Society of Judgment and Decision Making organised its first conference in 1980 and its presidents have included many of the familiar names in BE (e.g. Kahneman 1982-83, Loewenstein 2001-02, Ariely 2008-09).
When it comes to judgment and decision making research, you can find it published in journals that include those terms in the title, but also in e.g. marketing, organizational behaviour, behavioural finance, experimental economics and medical decision making among others. The academics producing the research we cite as practitioners might work in any of these departments or the "parent disciplines" of JDM.
This is one reason for the diversity of behavioural insights - while some of the ideas and theories are the same or connected somehow, each discipline will have a wealth of specialised research within it.
Finally, judgment and decision making also follows a certain paradigm - set of concepts and practices that define a scientific discipline:
what is to be observed and scrutinized
the kind of questions that are supposed to be asked and probed for answers in relation to this subject
how these questions are to be structured
what predictions made by the primary theory within the discipline
how the results of scientific investigations should be interpreted
For JDM, this broadly speaking includes:
cognitive biases and defaults that influence judgments of value, risk perceptions and immediate choice context
using experimental methods (deductive reasoning)
These practices largely come from the underlying disciplines of social and especially cognitive psychology and they have been recently critiqued by some scientists. It's an entire blog post on its own that I'll tackle in the future, but in the meantime, here are some things to start with:
Promises and perils of experimentation: The mutual internal validity problem
Just a Bunch of BS podcast with Michael Inzlicht: Replication Schmeplication? The State of Behavioral "Science"
What about behaviour change?
Despite what you might have heard, changing human behaviour is hard and requires a bit more than just adding some triggers and prompts that nudge people in or out of habits.
What each behavioural science practitioner needs in their own application domain varies, but I strongly believe in a holistic approach so my professional approach to behaviour change draws on multiple disciplines. It gives me a broader and more flexible toolkit that adapts to different clients, projects and domains.
You could think of it as a Venn diagram or perhaps a funnel - there are overlaps between the disciplines and it's also a bit like pouring many ingredients into a container. If you have another analogy, let me know - for now, we'll go with a funnel!
The basis of understanding human behaviour should always be first principles derived from evolutionary psychology: foundational psychological traits that are evolved adaptations - products of the evolutionary process based on our biological makeup or what helped our ancestors survive. If I have two conflicting explanations, it's a useful logic test to ask what would have made sense in the environment of evolutionary adaptedness (EEA) - the ancestral environment to which a particular species is adapted.
Then we have cognitive psychology: the study of the mind and the information processing that goes on inside our minds, including perception, attention, language, memory, thinking, and consciousness. On the flip side, social psychology: emotions, attitudes and beliefs, how people perceive themselves/their identity and how they behave in groups. Behavioural economics is part of the mix through these components, and its specific contributions on things like value and risk.
What is mentioned less often is learning theory: how we receive, process and retain knowledge during learning – including sources of motivation as well as cognitive, emotional, and environmental influences. I'm using the broadest definition as a short hand here - learning theory is often specifically used to refer to operant and classical conditioning, but it also links to a broader science of motivation, and is typically useful in designing interventions.
Putting together the beautiful mess
With the risk of simplification, I've tried to put together a rough sketch of how these theories fit together from my perspective. If you work in a specific application domain like behavioural finance or medical decision making, the picture will look slightly different - in the latter, you might be wise to consider the sociological and cultural context of behaviour too.
When it comes to behavioural design, we potentially add more dimensions like design principles but that largely depends on whether you are using the term literally (e.g. design of artefacts to influence behaviour) or more metaphorically - you will see both of these in use, which muddies the waters further.
What about 'behavioural science'?
All of the above could fall under 'behavioural science' - it's a broad umbrella term that refers to scientific disciplines that focus on human action and seek to generalize about human behaviour in society (some definitions even include animal behaviour!). If you wanted to include economics, a more accurate term would be 'behavioural and social sciences' which then also includes e.g. anthropology, sociology and linguistics even though they are often rejected by BeSci practitioners as 'not scientific enough'.
Professionally, I would describe myself paradigm agnostic - I like to consider insights from disciplines that have different methods and underlying premises (i.e. ontologies and epistemologies - for an explanation, see video below). Technically speaking, I sit somewhere in the middle between realists and relativists - while I agree that experiments and quantitative methods in general allow us to discover many things about the world, they are undeniably products of the socially constructed reality of the researcher and the scientific discipline.
Experiments can't measure everything that matters, and what is measured experimentally doesn't always matter.
I believe there is huge value in drawing on anthropology, linguistics and sociology because they often offer descriptive research that can help to provide context and explanations that can't be reached with experimental methods.
For some, this stance makes me less of an applied behavioural scientist - for me, it's a way of building a holistic perspective of behaviour and ultimately more effective behaviour change.