Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

Every tax unit files for refundable credits in the certified release: no EITC non-filers

Open
  • Is something wrong?
#1,133 0 comments 0 reactions 0 assignees View on GitHub

Maintainers usually reply within 1 day

Nobody has claimed this yet.

Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
48/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Active
Tech stack
python
Domain
data, machine-learning

Research direction

Start by reading us/spec/take_up.yaml and the frame adapter binding in policyengine_us_concepts.py, then trace how certified bundle inputs are constructed. The issue suggests seeding would_file_if_eligible_for_refundable_credit from eligible non-filer propensity data while preserving takes_up_eitc for non-claiming filers. Check the resulting EITC participation rate against the IRS-Census figures cited in the issue.

Written by the indexing model from the issue text.

Description

Summary

In populace-us-2024-spm-20260915 (bundle us-6.2.1), would_file_if_eligible_for_refundable_credit is stored as True for every tax unit (mean 1.0 in a policyengine.py managed simulation, 2024). policyengine-us documents the input as one "assigned during microdata construction based on propensity modeling" (default True). The build does not seed it: us/spec/take_up.yaml has no entry for it. (The frame adapter binds it to TakeUpThreshold(program="us.refundable_credit_filing") in policyengine_us_concepts.py, but the certified data carries no such draw.)

So in PolicyEngine, every tax unit entitled to the EITC files a return. The only source of EITC non-participation is takes_up_eitc.

Evidence

  • policyengine-us 2.2.1 eitc = min(phased-in, limitation) × takes_up_eitc × filer, where filer = required to file OR files voluntarily OR would_file_if_eligible_for_refundable_credit. With the last input always True, no entitled unit is a non-filer.
  • IRS-Census (CES-WP-24-75, Table 2): in tax year 2021, 4.6 million of the 5.7 million eligible non-claimants were non-filers; 1.1 million filed but did not claim.
  • policyengine-scorecard lane nta-eitc (PolicyEngine/policyengine-scorecard#151), us-6.2.1, CY2024: PE's EITC participation is 88.0%, against IRS's 80.8% (ACS) and 78% (CPS) for tax year 2022. Every PE non-participant has takes_up_eitc off; none is a non-filer.

Effect

  • EITC, refundable CTC (ACTC) and refundable State credits never miss a unit through non-filing. Where calibration fits SOI claims (State EITC claims by number of children), the weights absorb the difference, but the eligible-but-not-filing population is missing from the microdata.
  • Reforms that change filing incentives (for example a larger refundable credit, or simplified filing) cannot move non-filers into claiming, because none exist.

Suggested fix

Seed would_file_if_eligible_for_refundable_credit from a non-filer propensity, for example the IRS-Census eligible non-filer counts (CES-WP-24-75 Table 2: non-filers and filers), and keep takes_up_eitc for non-claiming filers only. Then check the EITC participation rate against IRS-Census again.

Dominant language
Python
Stars
0
Forks
5
Avg merge
1d 19h
Merged PRs (30d)
115

Getting set up

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from PolicyEngine/microcosm

All issues in PolicyEngine/microcosm

Similar issues

More Python issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.