Sarah Cotterill, Peter John, Liz Richardson

Institute for Political and Economic Governance

www.civicbehaviour.org.uk

Presentation to Randomised Controlled Trials in the Social Sciences: Evaluating Policy Interventions, York 2009

Pledge campaigns to encourage charitable giving: a randomised controlled trial

Overview

• Literature Review

• Research design

• Pilot study

• Next steps

Policy context

• Climate Change Pledge Schemes

• Pledgebank.com / We Are What We Do.

• Local Pledges

• CLG Community Contracts & Pledgebanks

Pledgebanks Desk Review

Cotterill & Richardson (2009) Pledgebanks Desk Review http://www.communities.gov.uk

Measuring success of pledge campaigns:– Publicise an issue - increase awareness;

– Success in attracting pledges (petition);

– Collecting data on individuals;

– Change behaviourDefra, 2008

Pledges and behaviour change

• Commitment to a type of behaviour can lead people to identify as someone who behaves in that way – and lead to change

(Bator and Cialdini 2000)

• Community Based Social Marketing– Commitments work best if: written down, public,

groups, voluntary.– Combine with other marketing approaches

(McKenzie-Mohr and Smith, 1999)

• Foot-in-the-Door techniques

Pledges and behaviour change 2

Observational studies suggest:

• Asking people to pledge can raise recycling rates - but may just be the personal contact (Reams & Ray 1993; Thomas 2006)

• Pledging can promote seatbelts (Geller, 1989) and cycle helmets (Ludwig 2005) as part of a promotional campaign.

• People more likely to stick to a non-smoking pledge if they were already thinking about it (Hallaq et al, 1976)

• Pledging can encourage voter registration and voter turnout (Greenwald et al 1987 – small experiment)

Research Design

Can a pledge scheme encourage people to adopt civic behaviour?

Research Questions:

• Are those who are asked to make a pledge more likely to later carry out the activity, compared to people who were not asked to pledge?

• Does making it public encourage people to pledge and carry out the activity?

Outcome measure

• Needs a civic behaviour that is observable, measurable, available across a large popn;

• Charitable donation: books

• Community Heart

• Children’s books and used mobile phones

• Measurement issues– Drop-off points; postage– Contamination: provide book/phone bags– Who is the book/phone from - unique identifiers

Population

• Residents in Woodhouse Park, Manchester

• Postcode list & PO Address Finder - exclude airport & businesses.

• Sampling unit = Households

• Approx 4772 households (2001 census)– 53% social housing (1950s council estate); 39% owned.– 79% house/bungalow; 21% flats

• 9th (of 32) most deprived ward in Manchester (2007 IMD)

Randomisation

• Control Group – invited to donate a children’s book or phone

• Pledge Group – asked to pledge that they will donate a children’s book or phone

• Pledge plus Publicity Group - asked to pledge that they will donate a children’s book or phone AND told the list of pledgers/donors will be published

POPULATION

CONTROL GRPLetter – advertises

opportunity to donate book/phone

PLEDGE GROUPSame letter plus: “Please return the

enclosed pledgecard “

CONTROLSend reminder with

enclosed return envelope.

NON-PLEDGERSSame as control

PLEDGERSReturn completed

pledgecard to them

Receive books

Send thank you and summary info

Check publicity

Receive books

Send thank you and summary info

Check publicity

Receive books

Send thank you and summary info.

Check publicity

PLEDGE & PUBLICITY

Same as pledge grp + told list will be posted

NON-PLEDGERSSame as control

PLEDGERSReturn completed

pledgecard and remind about publicity

Receive books Receive books

Send thank you and summary info.

Publicise involvement

Send thank you and summary info.

Publicise involvement

Sample sizes

• Need to know …– What proportion of control group will donate?– Difference between control and treatment response?– Institute of Fundraising, marketing companies

• We could guess …Control group - % who donate 3% 5% Pledge group - % who donate 5% 8% Size of each group 1000 1000 Alpha 0.05 0.05 Power 73.8 86

… Need to pilot

Pilot Study September 2009

• Purpose:– Check viability of larger experiment; – estimate group sizes; – test out letters, pledgecards, drop-off arrangements.

• 163 households in Woodhouse Park• Random allocation to 3 groups:

– Control Group – asked to donate book/phone– Pledge Group – asked to pledge a donation– Pledge Group – postage paid

• Drop off at library, community centre or post.

Analysis

• Outcome = % returning a book/phone

• Treatment = being asked to pledge. So

assume Intention to Treat analysis?

• Analysis at household level

• Simple comparison between 3 groups– Control, pledge, pledge + publicity

Next Steps

• Depending on outcome of pilot ….

• Larger experiment November 2009