Income Inequality in Tertiary Enrollment by Network Type, Time Series (Wagstaff Index)

Time series of income inequality in tertiary enrollment by network type (public vs. private), measured via the Wagstaff concentration index.

Overview

This figure tracks, over time, how concentrated enrollment in each network type — public vs. private higher education — is among higher-income households. Rather than looking at overall access, it applies the Wagstaff concentration index separately to enrollment in each network, allowing the two sectors’ income profiles to be compared directly and watched as they evolve.

Methodology

Time series of the Wagstaff concentration index applied to enrollment by network type (public vs. private), rather than to access overall — measuring whether enrollment in each network is concentrated among higher-income households, and how that concentration has moved over time. Computed directly from PNAD Anual and PNAD Contínua microdata, extracted standalone in this script rather than through the shared harmonized panel.

How to Cite

If you use this figure or the pipeline behind it, please cite both the dissertation and this specific analysis. References follow APA 7th edition.

Dissertation (in preparation; the entry will be updated after the defense):

Mançano, T. (2026). Inequality in access to tertiary education in Brazil: Household incomes, reforming policies, and the politics of who gets in (1990s–2020s) [Unpublished master’s thesis]. University of São Paulo.

This figure and pipeline:

Mançano, T. (2026, August 10). Income inequality in tertiary enrollment by network type, time series (Wagstaff index) [Figure and reproducible pipeline]. Open Data Analysis. https://mancano-tales.github.io/open-data-analysis/posts/wagstaff-rede-publica-privada-timeseries/

In text: (Mançano, 2026) — when citing several analyses from this catalog in the same work, APA distinguishes them as 2026a, 2026b, … in the order they appear in the reference list.

BibTeX:

@mastersthesis{Mancano2026Thesis,
  author = {Man\c{c}ano, Tales},
  title  = {Inequality in Access to Tertiary Education in Brazil: Household
            Incomes, Reforming Policies, and the Politics of Who Gets In
            (1990s--2020s)},
  school = {University of S\~{a}o Paulo},
  year   = {2026},
  type   = {Master's thesis},
  note   = {Unpublished; Graduate Program in Political Science}
}

@misc{Mancano2026_wagstaff_rede_publica_privada_timeseries,
  author       = {Man\c{c}ano, Tales},
  title        = {Income inequality in tertiary enrollment by network type, time series (Wagstaff index)},
  year         = {2026},
  month        = aug,
  howpublished = {Open Data Analysis, \url{https://mancano-tales.github.io/open-data-analysis/posts/wagstaff-rede-publica-privada-timeseries/}},
  note         = {Figure and reproducible pipeline. Source code: \url{https://github.com/mancano-tales/open-data-analysis}, folder posts/wagstaff-rede-publica-privada-timeseries/. Accessed YYYY-MM-DD}
}

A permanent version (Git tag + Zenodo DOI) will be linked here once the dissertation is defended; until then, cite the page URL above and add the date you accessed it (source code: https://github.com/mancano-tales/open-data-analysis, folder posts/wagstaff-rede-publica-privada-timeseries/).

Pipeline

Run these scripts in this order, from the project root (each one writes to data-raw/, which the next one reads):

1. shared-pipeline/pnadc/020_PNAD_Anual_Manual_Import_2001_2015.R — downloads the raw PNAD Anual 2001–2015 microdata (fixed-width .txt + SAS layouts) from the IBGE FTP into data-raw/pnad_anual_raw/<year>/ — plot.R reads these raw files directly
2. shared-pipeline/pnadc/000_PNADC_Download_Consolidate.R — (optional) pre-populates the PNAD Contínua cache in data-raw/pnadc_raw/; if you skip it, plot.R downloads the years it needs with PNADcIBGE::get_pnadc() into the same folder
3. plot.R — reads the raw PNAD Anual files in data-raw/pnad_anual_raw/ and the PNAD Contínua years in data-raw/pnadc_raw/; caches its extraction and bootstrap in data-raw/rede-publica-privada/ (sources shared-pipeline/utils/codigos_curso_pnad.R); writes the figure to output/figures/wagstaff-rede-publica-privada-timeseries/ — compare it with this post’s thumbnail.png

Reproducibility

Tier: A

This pipeline uses only public data, accessible via package/API without any credential (PNADcIBGE, censobr, sidrar, ipeadatar). Run the scripts in shared-pipeline/ in numeric order to reconstruct the intermediate data.