IESET.
Hypotheses·welfare architecture·welfare_transfer_us_arpa_expanded_ctc_2021

The American Rescue Plan Act (March 2021) expansion of the Child Tax Credit to USD 3000-3600 per child with full refundability and monthly disbursement (July-December 2021) produced a measurable and immediate decline in monthly child-poverty rate of at least 4 percentage points (Center on Poverty and Social Policy at Columbia time-series), with the credit's December 2021 expiration producing a corresponding immediate reversal — providing high-frequency event-window evidence on near-instantaneous cash-transfer-to-poverty mechanics.

Labour-supply effect on parental employment is hypothesised to be small (less than 1pp absolute change) at the 6-month horizon.

WEAKENEDengine/runs/welfare_transfer_us_arpa_expanded_ctc_2021

WEAKENED - SPM child poverty fell 4.5pp and rebounded 7.2pp; monthly CPSP and parental-LFP gates are not loaded

confidence cueThis test cuts against the claim as written or misses its pre-declared threshold.

policy briefNeeds review

In ordinary language

In plain terms, this asks whether ctc expansion indicator is actually linked to better or worse monthly child poverty rate from 2019 to 2023.

plain answer

SPM child poverty fell 4.5pp and rebounded 7.2pp; monthly CPSP and parental-LFP gates are not loaded

why it matters

This matters because welfare architecture claims should change belief only when they survive a pre-declared empirical test.

how the test works

It compares 1 country or place units from 2019 to 2023, using a event study design, with fixed effects for state and month.

what was measured
What changed
  • Ctc expansion indicator
What we checked
  • Monthly child poverty rate
  • Parental labour force participation
what this does not prove

A single test is not the whole truth. It narrows the claim under a specific sample, time period, and method. Strong policy conclusions need the pattern to survive nearby tests, alternative data, and serious objections.

verification

No evidence packet has been generated yet.

Results

engine/runs/welfare_transfer_us_arpa_expanded_ctc_2021
1007550250201920212023USA
illustrative sketch · run pending
No coefficients yet. When the model fires, this chart will show monthly_child_poverty_rate across 1 sampled countries over 2019–2023.
The shapes above are stylised — none of the lines are real data.
Placeholder for welfare_transfer_us_arpa_expanded_ctc_2021. Published chart will be generated from engine/runs/welfare_transfer_us_arpa_expanded_ctc_2021/chart_data.json.

Pre-registration

registration ordering unverified
first-spec commit 4c8ce8e · 2026-07-18T22:11:21Z
run generated · 2026-05-18T19:36:02Z
Run timestamp predates this path's first git-add commit (rebase, rename, or pre-git local run). Spec hash is still the path's first-add commit — not repository HEAD — but ordering is not a clean pre-registration proof.

The American Rescue Plan Act (March 2021) expansion of the Child Tax Credit to USD 3000-3600 per child with full refundability and monthly disbursement (July-December 2021) produced a measurable and immediate decline in monthly child-poverty rate of at least 4 percentage points (Center on Poverty and Social Policy at Columbia time-series), with the credit's December 2021 expiration producing a corresponding immediate reversal — providing high-frequency event-window evidence on near-instantaneous cash-transfer-to-poverty mechanics. Labour-supply effect on parental employment is hypothesised to be small (less than 1pp absolute change) at the 6-month horizon.

Falsification criterion — what would disprove this

set before the run · honoured after

This hypothesis is considered falsified if:

Refuted if the post-onset child-poverty ATT is below minus-4pp at 3-month horizon, OR if the post-expiration ATT does not show a corresponding rise of at least 3pp, OR if the parental-LFP ATT exceeds plus or minus 1pp at 6-month horizon.

formal test & threshold
test:      event_study_paired_onset_expiration_poverty_lfp
threshold: onset_3mo_poverty_att <= -4pp AND expiration_3mo_poverty_att >= +3pp AND abs(parental_lfp_att) <= 1pp

Method

Template
event_study
Fixed effects
state, month
Clustering
state
Sample
1 countries · 2019 – 2023
Evidence type
causal

Event study around 2021-07 expansion onset and 2022-01 expiration. Two events identified separately. Pre-trend 12 months, post-window 6 months each event.

Data

VariableSourceTransform
monthly_child_poverty_rate
outcome
world_bank_wdi:SI.POV.DDAYtier 2
level_pct
parental_labour_force_participation
outcome
bls:LNS11300000tier 1
level_pct
ctc_expansion_indicator
treatment
world_bank_wdi:SI.POV.DDAYtier 2
indicator
state_unemployment_rate
control
fred:UNRATEtier 1
level
pandemic_relief_indicator
control
fred:UNRATEtier 1
indicator

● ready  · ● pending  · ● reconstruct-needed

Detailed result card

Result card - welfare_transfer_us_arpa_expanded_ctc_2021

Verdict: WEAKENED - SPM child poverty fell 4.5pp and rebounded 7.2pp; monthly CPSP and parental-LFP gates are not loaded

Exact Local Benchmark

  • US Census SPM under-18 poverty fell 4.5 pp from 2020 to 2021.
  • It rebounded 7.2 pp from 2021 to 2022 after expiration.
  • Both annual SPM poverty gates clear with Census 90% MOE normal-approximation checks.

Caveats

  • Annual Census SPM is a conservative fallback for the preferred CPSP monthly series; parental LFP is not locally observed for the joint gate.

Sources

  • us_census:spm_child_poverty_rate -> us_census_spm_child_poverty_rate (data/vintages/us_census/spm_child_poverty_rate@2026-05-05T212332Z.parquet)

Generated by engine/runs/welfare_transfer_us_arpa_expanded_ctc_2021/replication.py at 2026-05-18T19:36:02+00:00

Strongest opposing argument

Every hypothesis ships with its charitable opposing argument. The framework earns credibility by handling objections at their strongest, not weakest.

Authored framework. Read the transparency note.