# Data Availability Statement

The following text is included at the end of the manuscript.

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**Data availability**

All data, analysis code, and documentation supporting the findings of this
study are provided in the Supplementary Materials accompanying this article.
The Supplementary Materials include: the complete-case analytic dataset
(`data/processed/analysis_dataset.csv`; 18,761 students in 1,377 schools in
six education systems), containing the outcome, all student- and school-level
predictors, their centered transformations, final student weights, and the 80
balanced repeated replication weights; the system-level dataset
(`data/processed/system_level_data.csv`); a full codebook documenting every
variable, its label, source, and recoding (`data/codebook.md`); the four
Python scripts that reproduce the entire pipeline from data extraction to
model estimation and figure generation (`code/`); documentation of the model
specification, centering, and estimation procedures (`docs/methods.md`) and of
data provenance (`docs/data_sources.md`); and all estimated model results and
publication figures (`output/`). Instructions for reproduction are given in
the Supplementary Materials README.

The analyses are based on the PISA 2022 international database, which is
publicly and freely available from the OECD at
https://www.oecd.org/en/data/datasets/pisa-2022-database.html. The raw source
files (`CY08MSP_STU_QQQ.SAV` and `CY08MSP_SCH_QQQ.SAV`) are not redistributed
in the Supplementary Materials because of their size and the OECD terms of
use; the processed analytic extract derived from them is provided in full, so
that all reported results can be reproduced without the original download.
The dataset contains no personally identifying information: records carry only
the anonymous school and student identifiers assigned by the OECD.

System-level indicators were obtained from the World Bank World Development
Indicators (GDP per capita, PPP, series NY.GDP.PCAP.PP.CD; fixed broadband
subscriptions per 100 people, series IT.NET.BBND.P2; both 2022, retrieved from
https://data.worldbank.org) and from ECLAC (2022).
