These are the slides from my presentation for Thammasat University School of Global Studies on 15 June 2022. I discuss some of the most recent developments and debates in behavioural economics with a focus on its application to sustainability issues. All the examples are taken from the course I teach as part of the Masters degree program in Social Innovation and Sustainability.
6. How Google encourage healthy eating
• Salad bar placed at entrance,
increasing sales by 20%.
• Sweets placed in opaque bins
rather than clear dispensers
resulted in 9% drop in calorie
intake from sweets.
• Previously water on tap and
sodas in fridge. Moved bottled
water to eye level and placed
soda at bottom of cooler,
replacing 47% of soda sales with
water.
Source Barden, P (2013) Decoded: The Science Behind Why We Buy, John Wiley & Sons, Chichester
7. Designing a sustainable food environment
University of Cambridge study
• 94,000 cafeteria meal choices from
2,140 repeat diners
What was the impact of morning from
1 in 4 to 2 in 4 plant-based choices?
• 40-80% more plant-based choices
• 33% reduction in carbon emissions
• 28% reduction in land use
• And no complaints! J
Source: Emma E. Garnett el al., "Impact of increasing vegetarian availability on meal selection and sales in cafeterias," Proceedings of the National Academy of Sciences (2019). www.pnas.org/cgi/doi/10.1073/pnas.1907207116
8. Nudges and equality of impact
In evaluating nudges, we should consider their distributional
effects. Specifically:
1. Who is likely to be helped, and who is likely to be hurt?
2. What are the expected effects on the least well-off? Will
nudges benefit those who are most in need of help?
3. Do the benefits to those who are helped exceed the costs to
those who are hurt?
4. Should we be customising and targeting?
Source: Sunstein, C.R. (2021) The distributional effects of nudges. Nature Human Behaviour, 2021 Nov 8. doi: 10.1038/s41562-021-01236-z
10. We are social animals
ENVIRONMENT
SOCIETY
INDIVIDUAL
11. The example of
Opower
• People often do not know how much energy they
are using
• They also do not know how much their neighbours
use
Allcott, H. & Rogers, T. (2014) The Short-Run and Long-Run Effects of Behavioral Interventions: Experimental Evidence from Energy Conservation, American Economic Review, 104 (10), 3003-37
12. Norms are always relative – handle with care!
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Descriptive only Descriptive + Injunctive
Short-Term Impact
Above average Below average
Source: Schultz et al. (2007) The Constructive, Destructive, and Reconstructive Power of Social Norms, Psychological Science, 18(5 ), 429-434.
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Long-Term Impact
Above average Below average
Change
in
energy
consumption
per
day
(kWh)
14. 25% is better, but still a minority
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2019 2020 2021
Sustainable consumption
%
consuming
sustainably
15. 30% is a minority and a trending norm*
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2019 2020 2021
Sustainable consumption
%
consuming
sustainably
*When we notice a change, we expect the change will continue in the same direction when it appears as a trend
16. Dynamic norms and sustainable eating
Source: Sparkman, G. & Walton, G.M. (2017) Dynamic Norms Promote Sustainable Behavior, Even if It Is Counternormative. Psychological Science, 28 (1), 1663-
1674.
17. Dynamic norms and equality
Source: Cheng, L. et al. (2020) Join us: Dynamic norms encourage women to pursue STEM, Current Psychology https://doi.org/10.1007/s12144-020-01105-4
20. “Don’t mess with Texas”
Texas’s most successful effort to reduce litter on highways (other
campaigns focusing on civic duty had failed to stop littering)
Decided they needed “a tough-talking slogan that would address
the unique spirit of Texas pride”
Within first year of campaign, litter reduced by 29%. In first six
years, 72% reduction in visible roadside litter (no threats,
mandates or nudges required!)
21. Nouns are more powerful than verbs
• Subtle linguistic cues increase
voting.
• Two conditions:
• Personal identity (“I am a voter”)
• Behaviour (“I vote”)
• Personal identity increased interest
in registering to vote.
• In two state-wide elections in the
United States, using personal
identity increased voter turnout as
assessed by official state records
Source: Bryan, C.J., Walton, G.M., Rogers, T., and Dweck, C. (2011) Motivating Voter Turnout by Invoking the Self. Proceedings of the National Academy of Sciences 108(31):12653-6.
22. Self-identity and mental associations
Wise, J. (2019) “It’s All in a Name: How to Boost the Sales of Plant-Based Menu Items”
23. Language and identity in food naming
USE LESS
• Meat-free
• Means less of what meat eaters like
• Vegan
• “Vegan” means “different from me”
(seen as an out-group in social media)
• Vegetarian
• “Vegetarian” means “healthy – but
unsatisfying – food”
• “Healthy restrictive”
• “Low fat” has “low appeal”
USE MORE (OR FIRST)
• Provenance
• Provenance is evocative (and a global
post-pandemic trend)
• Especially local provenance
• Flavour
• Flavour gets your mouth watering
and your tongue tingling
• Sensory descriptions trigger emotion
• Look and feel
• Look and feel drives appeal
Wise, J. (2019) “It’s All in a Name: How to Boost the Sales of Plant-Based Menu Items”
(https://www.wri.org/news/its-all-name-how-boost-sales-plant-based-menu-items)
26. Identity, social norms and proximity
• In a series of experiments in hotels, Robert Cialdini and others
explored how ‘social identity’ influenced norms that people would
follow.
• In one experiment, the following different messages were used:
1. “Help to save the environment” (Control)
2. “Join your fellow guests in helping to save the environment. In a study 75%
of the guests reused their towels.” (Guest identity)
3. “Join your fellow guests in helping to save the environment. In a study 75%
of the guests in this room reused their towels.” (Same Room identity)
4. “Join your fellow guests in helping to save the environment. Join your fellow
citizens.” (Citizen identity)
5. “Join your fellow guests in helping to save the environment. In a study 76%
of women & 74% of men reused their towels.” (Gender identity)
Source: Goldstein, Cialdini & Griskevicius (2008) A Room with a Viewpoint: Using Social Norms to Motivate Environmental Conservation in Hotels, Journal of Consumer Research, 35(3), 472-482.
27. Make normative appeals contextual
Source: Goldstein, Cialdini & Griskevicius (2008) A Room with a Viewpoint: Using Social Norms to Motivate Environmental Conservation in Hotels , Journal of Consumer Research, 35(3), 472-482.
0.0
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Standard Environmental
Message
Guest identity Same Room identity Citizen identity Gender identity
Towel
reuse
rate
(%)