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Arguments for using an automatic switching service for energy contracts. A field experiment.
Last registered on December 03, 2019


Trial Information
General Information
Arguments for using an automatic switching service for energy contracts. A field experiment.
Initial registration date
December 02, 2019
Last updated
December 03, 2019 11:12 AM EST
Primary Investigator
University of Muenster
Other Primary Investigator(s)
PI Affiliation
PI Affiliation
PI Affiliation
Additional Trial Information
In development
Start date
End date
Secondary IDs
In a field experiment, we test different arguments for registering for a service that automatically switches its customers’ energy contracts, aiming at minimizing their costs. We are in particular interested in whether people’s aversion to delegate a decision or their lack of knowledge regarding the advantages of such a service affect their decision to take up the automatic service. Our setup is an Email-campaign of a German service provider asking the customers to make use of the new service.
External Link(s)
Registration Citation
Feldhaus, Christoph et al. 2019. "Arguments for using an automatic switching service for energy contracts. A field experiment.." AEA RCT Registry. December 03. https://doi.org/10.1257/rct.5130-1.0.
Experimental Details
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
Registration for the automatic renewal service.
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Click on registration link.
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
We send Emails to all customers of the service provider who are currently enrolled in another service of the provider that reminds them that their current electricity contract expires before it is prolonged for another year. In this other service, the customers are offered different contracts that they can choose from via Email when they receive the reminder. In case they choose one of the contracts, the service provider takes over switching the contract. Hence, in this other service, customers have to take action to change their contract. The service provider offers a new service that completely takes over energy contract choices according to subjects’ revealed preferences (stored in their individual customer profile) in order to minimize costs (it is called automatic switching service). Thereby, the default is changed such that the contract is switched if no action is taken (however, in case customers appeal switching the contract, they are not switched).
For our experiment, we send Emails to all ~8,000 customers of the aforementioned other service asking them to switch to the automatic service. In a control condition, they receive a standard Email advertising the new service. In two further conditions, we make specific characteristics of the service more salient that may be off importance for customers when taking the decision to make use of the service.
Specifically, customers
1. either receive the standard Email promoting the service (treatment CONTROL)
2. are in particular told that they are still in control of their choices when making use of the service. (DELEGATION)
3. or told that the service helps them not to fall for the electricity provider's business model of making use of bonuses to make people get enrolled in expensive contracts. (BONUS TRAP)
Apart from emphasizing the respective treatment-related aspects, Emails are constant across all conditions.
Experimental Design Details
Randomization Method
Randomization Unit
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
No clusters
Sample size: planned number of observations
We send Emails to all ~8,000 current customers of the service provider. Assuming that 10 % of the customers open the Email, we expect to observe 300 decisions per treatment.
Sample size (or number of clusters) by treatment arms
The sample is equally allocated.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Is data collection complete?
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)