Effects of two innovative
techniques to apply incentives in online access panels
Michael Bosnjak* & Olaf Wenzel**
* University of Mannheim, Department of Psychology II, Germany
** SKOPOS Marketing Research, Cologne, Germany
Background
• Limited effects of incentives on response rates in Web-based access panel surveys
• Lack of innovative, Internet-specific techniques to implement incentives, such as
• Prepaid-Incentives, which proved to be successful on classical self-administered surveys (Church, 1993; Bosnjak & Tuten, 2003)
• Immediate notification of prize-draw results after survey
completion (Tuten, Galesic, & Bosnjak, 2004; Tuten, Galesic, &
Bosnjak, 2005)
Theoretical Bases
• Reciprocity:
Prepaid incentives evoke the norm of reciprocity(Gouldner, 1960) resp. activate reciprocity heuristics (Cialdini, 2002), leading to a higher probability for compliant behaviour compared to postpaid incentives.
• Immediacy Effect:
Prize draws (equal values) with immediate notification outperform prize draws with delayed notification (Tuten, Galesic, & Bosnjak, 2004) because people discount the utility of future events, which motivates them to prefer immediate over delayedrewards (Frederick, Loewenstein & O'Donoghue, 2003).
Research Questions and Hypotheses
• Effects of a mixed prepaid/postpaid incentive in relation to postpaid and prize draws?
-> Mixed prepaid/postpaid response rates should outperform postpaid and no incentives. No specific prediction in relation to price draws.
• Effects of an immediate prize draw notification information in relation to a delayed prize draw and both the prepaid/postpaid groups?
-> Immediate should outperform delayed prize draw and postpaid bonus points. No specific prediction in relation to the mixed prepaid/postpaid strategy.
• Costs per participant comparisons for different incentive implementation variants?
• Differences for answers to substantive questions between groups?
Methods I
Subjects:
1500 SKOPOS Europanel participants initially contacted (300 per group)
Materials and procedure:
Omnibus survey on (a) Web-ads for surveys, (b) pharmaceuticals, (c) tourism; average
completion time 10 minutes; fielded for one
week; no reminders
Methods II
Experimental groups:
• Group 1: Postpaid Bonus Points
4 postpaid bonus points (= EUR 2.-).
• Group 2: Mixed Prepaid/Postpaid
2 prepaid bonus points, 2 postpaid bonus points (paid for complete participation)
• Group 3: Immediate Price Draw
Immediate notification of prize draw result after complete participation. Winning propability:
1/50, prize amount: 200 bonus points (= EUR 100.-).
• Group 4: Delayed Prize Draw
Delayed notification of prize draw result. Winning propability: 1/50, prize amount: 200 bonus points (= EUR 100.-), notification one week following partricipation.
• Group 5: Control Group (no incentives)
Methods III
Dependent Variables:
• Response rates (completion rates)
• Drop-Out Rates
• Costs for 1% increase compared to the no incentives group
• Differences in response content
Results I: Completion Rates (in %)
48,0
53,3 54,0
45,7
38,0
0 10 20 30 40 50 60 70
postpaid mixed immmediate prize
delayed prize control
Results II: Drop-Out Rates (Counts)
Counts: Completion Counts: Drop-Out
postpaid 144 13
mixed 160 9
immmediate prize 162 6
delayed prize 137 11
control 114 16
Results III: Costs Per Participant
(in Panel Points: 2 PP = 1 €)
Absolute I (relative prize costs)
Absolute II (actual prize
costs)
Per complete I
Per
complete II
postpaid 576 576 4 4
mixed 920 920 5,8 5,8
immmediate
prize 648 600 4 3,7
delayed prize 548 400 4 2,9
control 0 0 0 0
Response Differences (for Tourism Items)
Sketch of main tentative results:
Two contradictory questions were embedded:
(a) the typical visitor of destination X matches my ideal self (the person I´d like to be similar to) and
(b) the typical visitor of destination X matches my undesired self (the person I don’t want to be similar to):
Greater ”yeah” saying tendency in mixed prepaid/postpaid condition!
! Lowest self-reported price consciousness in tourism for delayed prize draw participants.
