NUDGING TO REDUCE FOOD - TU Berlin · 2013-07-02 · NUDGE AND LIBERTARIAN PATERNALISM 3. THE...

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GEORG LIEBIGStudent of MSc. Integrated Natural Resource Management (HU Berlin)

NUDGING TO REDUCE FOOD WASTE- Presentation of a paper by Kallbekken and Sælen

copyrighted by Georg Liebig

OUTLINE

1. GENERAL CONSIDERATION

2. NUDGE AND LIBERTARIAN

PATERNALISM

3. THE RESEARCH PAPER

- INTRODUCTION

- DESIGN

- RESULT

- DISCUSSION

4. NUDGE IT!

Joshua Rappeneker

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Role of experiments (repetition)

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I. Test of the theoryCompare observed choices with theoretical prediction…IV. „Whispering in the ears of princes“ (Roth, 1995)Wind tunnels for new policy measures, institutions

1. GENERAL CONSIDERATION

Validity and experimental design (rep.)

NUDGING TO REDUCE FOOD WASTE

I. - need for high internal validity- Laboratory Experiments

Low external validityIV. - need for high external validity

- Field ExperimentsLower internal validity

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Nudges

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2. NUDGE & LIBERTARIAN PAT.NUDGING TO REDUCE FOOD WASTE

Design policies or “choice architectures” such that…– biased decision makers avoid making mistakes…

– while at the same time decisions of perfectly rationalpeople are not distorted

Libertarian Paternalism (rep.)

… are ways of influencing choice without limiting the choice set or making alternatives appreciably more costly in terms of time, trouble, social sanctions, and so forth. They are called for because of flaws in individual decision-making, and they work by making use of those flaws.

(Hausman & Welch 2010, p. 126)

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3. THE RESEARCH PAPER

Steffen Kallbekken, Håkon Sælen:

‘Nudging’ hotel guests to reduce food waste as a win–winenvironmental measure

Economics Letters 119 (2013) 325–327

Center for International Climate and Environmental

Reseach (CICERO) in Norway

NUDGING TO REDUCE FOOD WASTE

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Introduction

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- Large environmental impact of food provision- 1/3 of all food is wasted or lost

Reducing food waste = reducing environmental burden (e.g. GHG)

Nudge

3. THE RESEARCH PAPER

- influence consumption norms through external cues- 2 Nudges to reduce food waste (load less food)

reduce plate size a sign at the buffetnorm, visual illusion social norm

NUDGING TO REDUCE FOOD WASTE

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Design

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- Field experiment; observational study- 52 hotels in 3 groups

- observation for 2,5 months in total- pre-and post-treatment measurement of waste- control for: number of guests; food sales revenue

3. THE RESEARCH PAPER

control group plate size group salient sign group

Natural differences in plate size: 15- 28cm

Changed from 24 to 21 cm

„Welcome back! Again! And again! Visit our buffet many times. That´s better than taking a lot once“

38 hotels 7 hotels 7 hotels

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Results of the experiment I

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3. THE RESEARCH PAPERNUDGING TO REDUCE FOOD WASTE

19.5% reduction(p < 0.001)20.5% reduction(p < 0.001)

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3. THE RESEARCH PAPERNUDGING TO REDUCE FOOD WASTE

Results of the experiment II

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Results of observational analysis

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3. THE RESEARCH PAPERNUDGING TO REDUCE FOOD WASTE

1 cm reduction in plate size 2,5kg reduction of food waste (7.4%)

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Discussion

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- The nudges can substantially reduce food waste- Is it win-win?

PRIVATE- cost of plate size reduction: negative- cost of the sign: minimal- less food waste = financial saving for the hotelPUBLIC- 1 Kg food waste = 1.9 Kg CO2 e

-consumer satisfaction with buffet remains constant

3. THE RESEARCH PAPERNUDGING TO REDUCE FOOD WASTE

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Nudge it!

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Nudges for Sustainable Consumption

41% reduction in printing paper consumption

www.thenudge.de

ImplementationConceptualization Communication

NUDGING TO REDUCE FOOD WASTE

Defaults in printer settings

get to know, design and test green nudgesProjekttutorium „Nudge“ at HU Berlin (SS 13; WS 13/14)

…and other nudges!

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Ressources

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Steffen Kallbekken, Håkon Sælen (2013):‘Nudging’ hotel guests to reduce food waste as a win–winenvironmental measureEconomics Letters 119 (2013) 325–327

Daniel M. Hausman and Brynn Welch (2010):Debate: To Nudge or Not to NudgeThe Journal of Political Philosophy: Volume 18, Number 1, pp. 123–136

NUDGING TO REDUCE FOOD WASTE