Why I read it
I had a wonderful day at ResearchEd Surrey in October. I caught up with old colleagues from Farnham Heath End, Weydon, and beyond, met new colleagues from Twitter, and attended some enlightening talks. I even navigated Jade Pearce’s PowerPoint in her excellent session on evidence-informed teaching. Adam Robbins’ talk on behavioural change was particularly fascinating, and was based on the work of Damon Centola. Adam summarised Change excellently, adding humour and a schools-based focus. I knew immediately that I had to buy and review this book!
As the subtitle ‘How to make big things happen’ suggests, Centola sets out to understand how change can occur on a large scale. He explores how social media sites like Twitter became so popular, how the British Army successfully recruited so many men from a range of classes in World War 1, and what the true secret is to influencing people to adopt or change.
The book is based around the idea that we have weak ties and strong ties in our networks. Weak ties might be the majority of my Twitter followers who I do not know well; family members, friends, and more established colleagues would be examples of strong ties. Centola explores how both weak and strong ties can be useful to spread different types of messages, but crucially he assesses the types of messages and behaviours that can be changed or influenced through different ties and methods.
The book is full of research, by Centola himself (he conducts some wonderful studies), as well as other scientists, and finally a range of examples from various industries and moments in history. The prose is compelling, and the passion for the subject is ever present.
Simple vs complex contagions – like a virus, a simple contagion spreads easily across a network. Perhaps it’s something simple like a funny video or an inspirational tweet – people pass it on and it moves fast. However, complex contagions are ones that people resist. They are behaviours, ideals, or decisions that involve risk or change. These do not spread quickly or via weak ties. Therefore, we can use weak ties to effectively spread simple contagions, and strong ties for complex contagions – but it’s important to understand what we want to spread or change before planning the method. Both have their benefits and drawbacks, depending on the context.
Fireworks and fishing nets – building on ties, Centola uses the analogy of fireworks and fishing nets (see below) to represent how we might attempt to change behaviours. The fireworks model spreads information quickly and its reach is large, although the downside is seeing behaviour from a range of weak ties is less likely to influence you with a complex contagion. However, Centola’s research shows that people are more likely to adopt something complex when they are exposed to it by their strong ties; the fishing net model represents this – the spread will be slower as information travels from neighbour to neighour, but having interconnected movement means that people will see changes across more than one of their strong ties, influencing them to adopt. This is a seminal part of the book that is well worth reading in more detail than my short summary.
Snowballs, shotguns, silver bullets – so, we want to affect change in a village of 1000 people; here are some methods. Shotgun: this involves a broad approach, say targeting 10 people from all over the village and hoping this spread will reach the maximum number of people; the silver bullet approach involves identifying the most connected person, and putting all your energy into them spreading this message using their vast network; finally, the snowball approach is like the shotgun in terms of choosing 10 people, let’s say. However, this time you choose people who are connected or geographically close. The spread will be slower, but the connectedness of this group means they are likely to successfully adopt the change with high trust, and then it’ll begin to spread to others. All of these methods have their own merits and pitfalls, as discussed by Centola in this fascinating chapter. See the Favourite Moment heading.
Relevance and its 3 principles for adopting: Centola suggests that relevance is vital in our choice to adopt. For example, when we judge a change or innovation to be useful to us, or if it requires a degree of emotional excitement or loyalty, we are far more likely to adopt if we engage with people who are similar to ourselves. However, if behaviour change is based on believing a behaviour is widely accepted, the opposite is true; we want to see a diverse set of people adopting something.
Tipping point for change: Centola’s research, conducted in a fascinating social network study (you must read it!), involved planting ‘agents’ into a community to influence a group decision. It turns out that 25% is the magic number. If 25% of people in a community or group advocate a certain decision or set of behaviours, that can be a tipping point for the rest of the group to conform.
Favourite moment: Malawi Farming experiment
In Malawi, the traditional method of planting crops in rows wasn’t sustainable due to soil erosion and inefficiencies in holding water in low-rainfall years. The solution was pit-planting, i.e. digging a small pit for each crop to be planted in. But this was a big change and needed strong take up across the country to help the agricultural industry, and, in turn, food supplies. Scientists used the snowball, shotgun and silver bullet methods in different parts of Malawi – whereby some ‘agents’ were planted to help with uptake – and over a few years reviewed which method lead to the most number of farms adopting pit planting.
Over the course of the trial, the snowball method was the most effective, and they started with just two agent farmers per village. The progress might have been slow at first, but the trust they created in their fishing net meant that others saw first-hand how the new method could be trusted.
Another fabulous anecdote from the book – there are so many more.
Favourite quote – norms
‘The idea is a simple one: successful social change is not about information; it’s about norms. Social networks are not merely the pipes through which ideas and behaviours flow. They are also prisms that determine how we see those behaviours and interpret those ideas’
Key questions and reflections:
How could you adopt some of these principles to influence change in your organisation? Perhaps with a team? Perhaps with students?
Do you have the right infrastructure to initiate change and communication in both a fireworks and fishing net model?
Think about your organisation. Can you identify how and why behaviour or change has spread before? How could this be optimised?
Read this if…
You are a leader or manager interested in behaviour and change
You work within, or lead, a team and want to know how to improve dynamics and introducing change.