Digital Nudging in Multi-Stage Decisions: An Empirical Investigation of Spillover Effects on Pro-Environmental Employee Behavior

Last registered on October 27, 2025
View Trial History

Pre-Trial

Trial Information

General Information

Title
Digital Nudging in Multi-Stage Decisions: An Empirical Investigation of Spillover Effects on Pro-Environmental Employee Behavior
RCT ID
AEARCTR-0017094
Initial registration date
October 23, 2025

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
October 27, 2025, 8:53 AM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Locations

Country
Germany
Region

Primary Investigator

Name
Natalie Rupp
Affiliation
Ulm University
Contact Primary Investigator

Other Primary Investigator(s)

PI Name
Maximilian Habla
PI Affiliation
Ulm University
Contact Investigator
PI Name
Christopher Tille
PI Affiliation
Ulm University
Contact Investigator
PI Name
Mischa Seiter
PI Affiliation
Ulm University
Contact Investigator
PI Name
Steffen Zimmermann
PI Affiliation
Ulm University
Contact Investigator

Additional Trial Information

Status
In development
Start date
2025-10-24
End date
2025-12-31
Keywords
Behavior, Environment & Energy, Firms & Productivity, Governance
Additional Keywords
Digital Nudging, Pro-Environmental Behavior, Employee Decision-Making, Multi-Stage Decision Processes, Sustainability, Behavioral Spillover Effects, Contextual Spillover Effects, Temporal Spillover Effects
JEL code(s)
Secondary IDs
Prior work
This trial is based on or builds upon one or more prior RCTs.
Abstract
Organizations are major contributors to climate change and face growing pressure to adapt their operations. Since employees translate organizational policies into daily practices, influencing employee behavior has emerged as a critical lever for reducing environmental impact. Digital sustainability nudging, behavioral change interventions embedded in digital environments, offers promise in this regard but is typically examined for apparently isolated decisions. Prior research, however, indicates that interventions promoting pro-environmental behavior can spill over to subsequent decisions across behaviors, contexts, or time.
Yet, no study has systematically examined whether digital sustainability nudges generate all three spillover types. Understanding this issue is highly relevant, as spillover effects determine whether such nudges produce broader positive impacts, unintended negative consequences, or remain confined to the immediate target behavior. Our study therefore investigates whether digital sustainability nudging triggers behavioral, contextual, and temporal spillover effects on sustainable employee decision-making.
External Link(s)

Registration Citation

Citation
Habla, Maximilian et al. 2025. "Digital Nudging in Multi-Stage Decisions: An Empirical Investigation of Spillover Effects on Pro-Environmental Employee Behavior." AEA RCT Registry. October 27. https://doi.org/10.1257/rct.17094-1.0
Sponsors & Partners
Experimental Details

Interventions

Intervention(s)
Intervention (Hidden)
We will collect data from online click workers located in the US who are at least 18 years old. Each participant will be randomly assigned to the control or the treatment (nudge) group.
Intervention Start Date
2025-10-24
Intervention End Date
2025-12-31

Primary Outcomes

Primary Outcomes (end points)
Sustainable decisions in the first and second decision stages and in the follow-up session with the same decision scenarios.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
In this study, participants complete two decision-making tasks:
- Business Trip Booking: Participants choose a travel mode (train or plane) and subsequently select a fare class (first/business or standard/economy class).
- Procurement Decision: Participants choose between two laptops.
The order of these two tasks is randomized across participants.
Participants are randomly assigned to two experimental groups:
- Control Group: No digital sustainability nudge is presented.
- Treatment (Nudge) Group: Participants receive a digital sustainability nudge during the first decision stage of the business trip booking task or during the procurement decision task.
Experimental Design Details
On the welcome page of the study, participants are informed about the procedure, including the presence of attention checks and potential exclusion criteria. Participants are then presented with a simulated business scenario. They are instructed to imagine themselves shortly before the end of their workday, needing to complete two simple work-related tasks. The order of these two tasks is randomized. Accordingly, participants in the treatment group receive a digital sustainability nudge during their first task only.
- Procurement Decision: In the procurement scenario, participants choose between two identical laptops. The only difference between the two products lies in their price, energy efficiency and CPU model speed. The more energy-efficient laptop is labeled as the sustainable option by the digital nudge.

- Business Trip Booking: The business trip booking task involves two decision stages: i) Mode of Transport: Participants choose whether to travel by plane or train. The two modes differ in CO₂ emissions, price, and travel time. The plane offers a shorter travel time, the train is more expensive but more environmentally friendly. In the nudge condition, participants receive a digital nudge indicating that the train is the sustainable option. ii) Fare/Class Selection: After selecting the mode of transport, participants choose a fare class. For trains, this means choosing between first and standard class; for planes, between business and economy class. The lower fare options (standard/economy) are both less expensive and have a smaller carbon footprint. No nudges are presented at this stage.

After completing both tasks, participants are asked to briefly explain the reasoning behind their choices. To examine potential temporal spillover effects, the study includes a second measurement point. After a waiting period, participants complete the same two tasks again, this time without any nudges.
Randomization Method
Participants will be randomly assigned to the experimental groups by a designated function of the software oTree.
Randomization Unit
Randomization will be done at the participant level.
Was the treatment clustered?
No

Experiment Characteristics

Sample size: planned number of clusters
No clusters
Sample size: planned number of observations
Our sample size will be calculated based on the results of our experimental pre-test using G-Power Analysis.
Sample size (or number of clusters) by treatment arms
Our sample size will be calculated based on the results of our experimental pre-test using G-Power Analysis.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Supporting Documents and Materials
IRB

Institutional Review Boards (IRBs)

IRB Name
Institutional Review Board of the Faculty of Mathematics and Economics (IRB-MAWI), University of Ulm
IRB Approval Date
2025-10-14
IRB Approval Number
Project 2025-01
Analysis Plan

Post-Trial

Post Trial Information

Study Withdrawal

There is information in this trial unavailable to the public. Use the button below to request access.

Request Information

Intervention

Is the intervention completed?
No
Data Collection Complete
Data Publication

Data Publication

Is public data available?
No

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials