Preferences for Pension System Size Along the Bismarckian-Beveridgean Spectrum

Last registered on October 01, 2025

View Trial History

Pre-Trial

Trial Information

General Information

Title

Preferences for Pension System Size Along the Bismarckian-Beveridgean Spectrum

RCT ID

AEARCTR-0016222

Initial registration date

September 26, 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 01, 2025, 7:11 AM EDT

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

Locations

Country

United Kingdom of Great Britain and Northern Ireland

Region

England, Scotland, Wales

Primary Investigator

Name

Ernesto Anguita

Affiliation

University of Antwerp

Contact Primary Investigator

Other Primary Investigator(s)

PI Name

Sunčica Vujić

PI Affiliation

University of Antwerp

Contact Investigator

PI Name

Nick Deschacht

PI Affiliation

KU Leuven

Contact Investigator

Additional Trial Information

Status

In development

Start date

2025-09-28

End date

2025-10-31

Keywords

Behavior, Electoral, Finance & Microfinance, Labor, Welfare

Additional Keywords

Pensions, Pension Systems, Social Security, Progressivity, Bismarckian, Beveridgean

JEL code(s)

H23, H24, H55, J38

Secondary IDs

Prior work

This trial does not extend or rely on any prior RCTs.

Abstract

Cross-national evidence shows that pension schemes with more equal benefit distributions (Beveridgean schemes) tend to be smaller than those that closely mirror individuals’ prior earnings or contributions (Bismarckian schemes). However, empirical evidence on the microfoundations of this relationship is missing. This gap limits the ability to infer the social limits of the redistributive power that can be attained through public pensions and to understand the relative importance of economic and social motivations for individuals’ preferences. To fill this gap, this experiment investigates the effect of different levels of pension scheme's transfer progressivity on individuals' preferences for the size of the scheme, measured by the contribution rate they are willing to apply.

External Link(s)

Registration Citation

Citation

Anguita, Ernesto, Nick Deschacht and Sunčica Vujić. 2025. "Preferences for Pension System Size Along the Bismarckian-Beveridgean Spectrum." AEA RCT Registry. October 01. https://doi.org/10.1257/rct.16222-1.0

Sponsors & Partners

Experimental Details

Interventions

Intervention(s)

Individuals are randomly assigned to pension schemes that differ in their levels of transfer progressivity. We use the global measure of intragenerational redistribution proposed by Klos et al. (2022) to simulate 5 State Pension designs. Individuals are asked to state the employee contribution that they consider appropriate for the pension scheme to which they are assigned.

Additionally, we implement treatments that vary the level of government subsidy to the pension scheme and the method used to calculate individuals’ lifetime earnings. While the former affects both individuals’ own pension benefits and those of the highest and lowest contributors, the latter affects only individuals’ own pension entitlements.

Pension entitlements are determined by employees' contribution rate to the pension scheme. Respondents are able to dynamically observe how a pension design scenario with a specific contribution rate level affect 1) their current earnings, 2) their future pension outcomes, 3) the future pension outcome of top contributors, and 4) the future pension outcomes of lowest contributors.

References:
Klos, J., Krieger, T., & Stöwhase, S. (2022). Measuring intra-generational redistribution in PAYG pension schemes. Public Choice, 190(1), 53-73.

Intervention (Hidden)

Transfer progressivity treatments (TP):

TP1: Individuals receive a strictly Beveridgean design. Pension entitlements are distributed uniformly across all pensioners

TP2: Individuals receive a near-Beveridgean design. The maximum gross pension of top contributors is 36% higher than the minimum gross pension of lowest contributors.

TP3: Beveridge-leaning encompassing design. The maximum gross pension of top contributors is 96% higher than the minimum gross pension of lowest contributors.

TP4: Bismarck-leaning encompassing design. The maximum gross pension of top contributors is 313% higher than the minimum gross pension of lowest contributors.

TP5: Bismarckian design. The maximum gross pension of top contributors is 560% higher than the minimum gross pension of lowest contributors.

Intergenerational generosity treatments (IG):

IG1: Low government contribution. The government adds resources to the pension scheme equivalent to 40% of the total lifetime contributions paid by employees and employers.

IG2: Medium government contribution. The government adds resources to the pension scheme equivalent to 65% of the total contributions paid by employees and employers.

IG3: High government contribution. The government adds resources to the pension scheme equivalent to 90% of the total contributions paid by employees and employers.

Lifetime earnings calculation treatments (LEC):

LEC1: Standard. An individual’s earnings across their lifetime will follow the path of a synthetic worker in the same sector, remaining in the same earnings decile within that sector throughout their lifetime.

LEC2: Underestimated. An individual’s earnings across their lifetime will equal 90% of the earnings that would result by following the path of a synthetic worker in the same sector and remaining in the same earnings decile within that sector throughout their lifetime.

Intervention Start Date

2025-09-28

Intervention End Date

2025-10-31

Primary Outcomes

Primary Outcomes (end points)

Preferred employees' contribution rate. This variable is used as a measure of the preferred size of the pension scheme given a certain level of transfer progressivity.

Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)

Secondary Outcomes (explanation)

Experimental Design

We recruit 1,500 working age individuals residing in Great Britain using Prolific. The experiment has been desgined in Qualtrics.

The experiment comprises three main parts that are shown to participants once they have given consent to participate.

First, they are presented with a questionnaire about their current and past labour market experience. This information is used to project each individual’s lifetime earnings and pension entitlements under different levels of transfer progressivity and contribution rates.

In the second part, participants are informed of their position on the lifetime earnings distribution and are presented with two different fictitious pension schemes. These schemes differ in how pension entitlements are distributed. Participants are able to see the impact of different contribution rates on their current net earnings and their future net pension, as well as on the minimum and the maximum net pensions available across the population. Additionally, they observe the share of the population that will receive the minimum and the maximum pension.

The experiment ends with a second questionnaire asking about their financial expectations, their financial profile and their social perceptions.

Experimental Design Details

Randomization Method

Qualtrics randomizes the designed treatments among participants.

Randomization Unit

Randomization is made at the individual level.

Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters

Our observations are not clustered.

Sample size: planned number of observations

1,500 individuals.

Sample size (or number of clusters) by treatment arms

There are three treatment levels distributed across respondents.

Participants are first randomized on the level of transfer progressivity that they receive in the first scheme they receive.

25% of participants (~375) receive a strictly Bismarckian pension scheme.
25% of participants (~375) receive a near Beveridgean pension scheme.
16.67% of participants (~250) receive a Beveridge-leaning encompassing scheme.
16.67% of participants (~250) receive a Bismarck-leaning encompassing scheme.
16.67% of participants (~250) receive a Bismarckian scheme.

Participants are also randomized on the degree to which the pension scheme is subsidized by the government.

33.33% of participants (~500) receive a pension scheme with a low government contribution.
33.33% of participants (~500) receive a pension scheme with a medium government contribution.
33.33% of participants (~500) receive a pension scheme with a high government contribution.

Finally, participants are also randomized on the way in which their lifetime earnings are calculated.

50% of participants (~750) are assumed to earn 100% of the earnings they would receive if they followed the path of a synthetic worker in the same sector and remaining in the same earnings decile within that sector throughout their lifetime.
50% of participants (~750) are assumed to earn 90% of the earnings they would receive if they followed the path of a synthetic worker in the same sector and remaining in the same earnings decile within that sector throughout their lifetime.

Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

1st Treatment: Contribution rate vs. progressivity. - Standard deviation assumed: 0.06 - Proportion in treatment: 20% - MDE: 0.011 2nd Treatment: Contribution rate vs. generosity - Standard deviation assumed: 0.05 - Proportion in treatment: 33% - MDE: 0.009 3rd Treatment: Contribution rate vs. calculation rule - Standard deviation assumed: 0.05 - Proportion in treatment: 50% - MDE: 0.009

Supporting Documents and Materials

IRB