Social Norm Theory
( Cialdini, Kalgren & Reno, 1990 ) mm-dd-yy | 2
› Injunctive norms: The behavior commonly
(dis)approved. (Social) Sanction, Reward
› Descriptive norms: The behavior commonly displayed.
› Salience is important
› Aligned norms are stronger

Project 1
› Promoting Orderly Bike Parking in Groningen

Kaartje binnenstad

Previous Studies on Parking Problems
› 44% Sees inappropriate parking as a problem
› 67% Shopping
› 64% Park < 30 minutes
› 42% Not enough parking spaces

Making the injunctive norm salient
Prohibition sign: 37% Prescriptive sign: 60%

Making the injunctive norm salient
› How?
› Please park your bicycle within the green area 

PROPOSED FIELD EXPERIMENT
› Method:
• Pre and post intervention
• Observational
› Outcome measures:
• % Bikers conforming to parking norm
• % Bikers being socially sanctioned

Project 2: Reducing cars driving to city

Car
Public
Transit
Bike
Walk
> 10km Public
Transit
5-10km PT or bike
< 5km Bike or walk
Behavior

Segmented approach

39%
Transportation modes for 5-10 km
1%
1%
45% car public transportation bicycle walk other
14%

Social Norms
› Theoretical gaps:
• Behavior suggestions: 1 vs. 2 alternatives
• Norm effectiveness: perception vs. actual

Action Research
› 4 conditions (all groups receive information + incentive)
• Bike norm info
• Public transport norm info
• Bike + PT norm info
• Control

Action Research
› Procedure
• Telephone Survey
• Mail packages
• Outcome measures
• Telephone follow up survey
• Objective assessment

The message
(For people 5-10 km)
› Many people believe that using sustainable transportation is the right thing to do. (injunctive)
› 53% of people in your neighborhood use a bike or public transportation to go to work everyday.
(descriptive)
› Join us in making Groningen the most sustainable city in the Netherlands!
› Please use a bike or public transportation when you go to work.

Expected outcomes
› Practical
• Decrease car use in city for segmented area
› Theoretical hypotheses
• Experimental groups will reduce car use more than control
• Perception of norm may interact with reported norm

Project 3: The use of norms on testimonials

Purpose of the study: increase preference for the tram

“ Well, I think the tram is a good plan, as long as it will go past
Euroborg”
“I used the tram in Rio de
Janeiro, Brussels,
Amsterdam, and a couple of other city's. I really like it”

Which message works best?
› Injunctive: “The tram will be an appropriate means of
transportation”
› Descriptive: 60% of people traveling within Groningen will take the tram
When both norms align tram preference will increase

Which message works best… and for whom?
› Target group: People working in Groningen and living outside of Groningen
› Important: Identify with the individual providing the testimonial
Vs.
Identification with models will increase tram preference

K.E.Keizer@rug.nl
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