La Bonne Alternance - Firms’ behavioural response to unsolicited applications for apprenticeship positions

Last registered on September 08, 2022


Trial Information

General Information

La Bonne Alternance - Firms’ behavioural response to unsolicited applications for apprenticeship positions
Initial registration date
September 01, 2022

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
September 08, 2022, 11:43 AM EDT

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



Primary Investigator

University of Montpellier & Paris School of Economics

Other Primary Investigator(s)

PI Affiliation
Copenhagen Business School

Additional Trial Information

On going
Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
The goal of the study is to analyze the effects of an internet-based recommender system that identifies establishments likely to hire apprentices in a geographical area of interest. Such a system is expected to improve the targeting of unsolicited applications, thereby enhancing the quality and number of matches between firms and candidates to apprenticeship programs. The system analyzed is a French website, La Bonne Alternance (LBA), rolled out by the French Public Employment Service (Pôle Emploi) in 2018. It is receiving in 2021 about 1.5 million visits per year and displays about 500.000 plants. It has received sizable attention in the public debate because of both its audience and the difficulties to foster high-quality apprenticeships in France. The experiment started in September 2021 and will run until the end of September 2022.
External Link(s)

Registration Citation

Briole, Simon and Clément Brébion. 2022. "La Bonne Alternance - Firms’ behavioural response to unsolicited applications for apprenticeship positions." AEA RCT Registry. September 08.
Experimental Details


The LBA website is jointly managed by an inter-ministerial mission for apprenticeship training (“La mission apprentissage”) and Pôle Emploi (PE), the French Public Employment Service. It aims at improving the number and the quality of apprenticeship contracts by fostering and improving the outcome of unsolicited applications. On the website, one can find a list of establishments – with their contact details – that are likely to hire apprentices in the selected occupation, at the preferred level of studies and in the geographical area of interest.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
(i) the number of apprenticeships signed; (ii) the quality of these apprentices and (iii) the short and long term retention rates in the plants
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
The estimation strategy consists in inhibiting some of the establishments displayed on the website in a two-step randomisation design à la Crépon et al (2013). First, we randomly draw the proportion of plants to remain on the website (0%, 25%, 75%, 100%) in each of the 420 local labour markets (“bassins d’emplois”). Second, we randomly select plants to remain on the website according to the relevant proportion for their local labour market.
Experimental Design Details
Randomization Method
Randomization done in office by a computer
Randomization Unit
Two-step randomisation design à la Crépon et al (2013) : at the plant level and at the local labour markets (“bassins d’emplois”) level
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
About 500,000 plants
Sample size: planned number of observations
About 500,000 plants
Sample size (or number of clusters) by treatment arms
We randomly selected 1/10th of the local labour markets where to display 100% of the companies selected by PE’s algorithm, 4/10th of the local labour markets where to display 75% of the establishments selected by the algorithm, 4/10th of the areas where to display 25% of the establishments selected by and the algorithm, and 1/10th of the areas where 0% should remain
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
IRB Approval Date
IRB Approval Number
Analysis Plan

Analysis Plan Documents

LBA experiment Pre Analysis Plan

MD5: 021d37c70d907337da53d446810ab273

SHA1: 7acb3926adcc6b31e8c846c49360c46cbdbe917c

Uploaded At: September 01, 2022


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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