How does choice affect learning?

Last registered on June 12, 2024


Trial Information

General Information

How does choice affect learning?
Initial registration date
April 19, 2021

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
April 20, 2021, 6:33 AM EDT

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

Last updated
June 12, 2024, 1:45 PM EDT

Last updated is the most recent time when changes to the trial's registration were published.



Primary Investigator

Central European University

Other Primary Investigator(s)

PI Affiliation
Vienna University of Economics and Business

Additional Trial Information

Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
In many cases people receive information about products after their choice, which in turn affects future buying/selling decisions (e.g. financial assets, switching markets). This project studies how choice itself - beyond the effect of ownership - changes how people use information to update their beliefs about products. In the lab, using a between-subject design, participants learn about the fundamental quality
of financial investments by observing price changes. We examine how they update beliefs after positive (e.g. price increase) and negative (i.e. price decrease) signals. The goal is to compare people who choose the investments themselves to people who receive the same investments exogenously. This comparison allows us to isolate the effect of choice from the effect of ownership.
External Link(s)

Registration Citation

Hajdu, Gergely and Balazs Krusper. 2024. "How does choice affect learning?." AEA RCT Registry. June 12.
Experimental Details


Participants learn about the fundamental quality of financial investments by observing price changes. We examine how they update beliefs after positive (e.g. price increase) and negative (i.e. price decrease) signals. Participants own some of the investments: in the Choice treatment they choose themselves while in the Allocation they receive investments exogenously.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Belief changes in percentage points.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Recall accuracy of previous price changes and beliefs.
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
Participants face 6 investment opportunities in the experiment. Each investment has the same initial price and a fixed but unknown quality s_i. In each round, each investment price either increases - with probability s_i -, or decreases - with probability 1-s_i. There are 20 rounds. In each round, participants observe the sequence of all previous prices and they have to predict each investment's probability of a price increase. Participants are incentivized to make accurate predictions.

Participants are randomly assigned to one of two treatment conditions after round 4. In the Choice condition, they have to choose 3 investments. In the Allocation condition, they receive the 3 investments with the highest current prices. In both conditions, ownership means that the participants receive a bonus based on the the final price of the own investments. Choosing or receiving investments will come as a surprise in round 4.

To learn about the mechanism, we add two unexpected recall questions. First, we ask participants about price changes of two randomly selected investments in the previous round. They receive this question in a randomly selected round between round 14 and 16. Second, we ask participants about their predictions of two randomly selected investment in the previous round. They receive this question 3 rounds after the price recall task. For each recall task, participants are incentivized to give accurate answers.
Experimental Design Details
Randomization Method
Randomization is done by the computer.
Randomization Unit
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
750 participants.
Sample size: planned number of observations
750 participants * 6 investments * 16 rounds = 72,000 observations
Sample size (or number of clusters) by treatment arms
Choice treatment: 375 participant
Allocation treatment: 375 participant
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
Central European University Economics Doctoral Committee
IRB Approval Date
IRB Approval Number
Analysis Plan

Analysis Plan Documents

Pre-Analysis Plan

MD5: 40ebfb070bae16cfdb7e3270f2765bfd

SHA1: ca0f3234e5f7daccd7b2391d1a02fc76d7876444

Uploaded At: April 19, 2021


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Is the intervention completed?
Data Collection Complete
Data Publication

Data Publication

Is public data available?

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials