Sebastian Tonke

So:

✅ Identity can be shaped

✅ Actions ONLY shape how we see ourselves when the identity-action link is salient.

✅ Linking behavior to identity creates lasting change.

Paper ➡️ [https://tinyurl.com/3b7jha2b]

9/9

The result?

📉 Non-payment for water nearly eradicated
💰 ROI: over 3,000%
🪙 Cost: ~22 cents per household
🧠 And people liked the messages

8/9

Why?

Identity appeals induce a permanent intrinsic motivation: Individuals continue to see their actions as a credible signal about their identity.

7/9

And long term?

⚠️ Simple reminders backfired. Payments dropped below even the control group after the intervention ended. A zero effect over the span of a year.

✅ Identity appeals, by contrast, sustained high payments.

6/9

👉 Only identity appeals changed how people saw themselves.

People who didn’t pay under identity appeals felt less like responsible citizens afterward. They updated their self-perception based on their actions.

No change under simple reminders.

5/9

I tested two kinds of messages placed on the water bills:

✅ Identity appeals
→ Creating a link between paying and being a “responsible citizen.”

❌ Simple reminders
→ No mention of identity

Both boosted short-term payments.

But the long-term effects? Fundamentally different.

4/9

To find out, I ran a large-scale field experiment:

📊 11,434 households
📬 29,677 hand-delivered messages
💧 A public water utility struggling to collect water bill payments

3/9

Our identity (or self-perception) influences a host of behaviors such as educational investments, political participation, and also civic duties.

But here’s a question:

👉 Can actions change how we see ourselves?

And if so… can policymakers use that to induce sustained behavioral change?

2/9

🤔 How do people form beliefs about who they are?

🤔 Can identity be shaped to change economic behavior?

A 🧵 on my paper: “Shaping Identity” recently accepted at JPE Micro!

#econsky
#publicationalert
1/9

Very much looking forward to this! Don't forget to submit your paper or abstract by May 15!

❗Deadline Approaching for SEEDEC 2025!

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⏳ Registration deadline: March 1, 2025

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Inspired by @tapiorasanen.bsky.social, here is a starter pack for economists conducting field experiments 🤓🫶

Please let me know who is missing – and share widely! 🚀

go.bsky.app/9hev4gN

We're hiring! #econsky #econjobmarket

Predoctoral Research Assistant (m/f/div) for Project on International Educational Migration

We are hiring a Predoc! Join our international research team at the MPI to work on an RCT focused on international educational migration. Based in Bonn, Germany, with competitive pay and exciting opportunities for professional development. Apply here: career.coll.mpg.de/jobposting/c...

Saving water via text message In Namibia, providing a short list of specific saving strategies reduced water consumption by 5% while simply raising awareness and asking households to find their own strategies was ineffective

🆕 In Namibia, providing a short list of specific saving strategies reduced water consumption by 5% - simply raising awareness & asking households to find their own strategies was ineffective.

Sebastian Tonke outlines evidence on effectively promoting water conservation: voxdev.org/topic/energy...

Please RT: Our fundraising at @malengo has been slow! We want to support as many students as possible on their journey from Uganda to a Bachelor's degree in Germany. Please support us! Donations are tax deductible in the US and Germany. Details at malengo.org/donate. Thanks!

So great to see this published online at the #JDE 🥳

👉 RCT to curb water demand in Namibia during severe #waterscarcity.
👉 Providing a short list of actionable and specific saving tips reduces consumption by 5%.

#Sustainability #ClimateCrisis #boost
Get the paper here (OA) 👉tinyurl.com/23fxufzs