IESET.
Hypotheses·distribution·tax_inequality_italy_irpef_flattening_2002_2024

Italian IRPEF flattening (Berlusconi 2003 bracket reduction from five to three brackets, Renzi 2014 EUR 80 monthly bonus, Meloni 2024 three-bracket structure) over 2002-2024 produced a measurable rise in the top-10 pretax income share but a flat-to-declining top-1 share, consistent with the view that bracket-flattening compresses upper-middle-class progressivity rather than substantially benefitting the very top in a high-evasion-rate jurisdiction.

The discriminating test is the divergence between top-1 and top-10 share trajectories over the period.

INCONCLUSIVEengine/runs/tax_inequality_italy_irpef_flattening_2002_2024

INCONCLUSIVE_DATA_PENDING — treatment 'ita_2003_bracket_flattening' has no within-country variation under country fixed effects

confidence cueResult card produced; verdict unclassified.

policy briefCoverage too thin

In ordinary language

Over a long period, do more market-oriented institutions translate into higher income or productivity, once the comparison looks beyond a single success story?

plain answer

This test cannot make a firm call yet. treatment 'ita_2003_bracket_flattening' has no within-country variation under country fixed effects

why it matters

Distributional claims often sound morally clear but are empirically complex. This test asks whether the proposed channel explains real differences across places.

how the test works

It compares 10 country or place units from 1995 to 2024, using a panel fe design, with fixed effects for country and year.

what was measured
What changed
  • Ita 2003 bracket flattening
  • Ita 2024 bracket flattening
What we checked
  • Top 1pct pretax income share
  • Top 10pct pretax income share
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/tax_inequality_italy_irpef_flattening_2002_2024
1007550250199520102024ITAFRADEUESPNLDBELAUT
illustrative sketch · run pending
No coefficients yet. When the model fires, this chart will show top_1pct_pretax_income_share across 10 sampled countries over 1995–2024.
The shapes above are stylised — none of the lines are real data.
Placeholder for tax_inequality_italy_irpef_flattening_2002_2024. Published chart will be generated from engine/runs/tax_inequality_italy_irpef_flattening_2002_2024/chart_data.json.

Pre-registration

registration ordering unverified
first-spec commit 4c8ce8e · 2026-07-18T22:11:21Z
run generated · 2026-06-29T17:51:14Z
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.

Italian IRPEF flattening (Berlusconi 2003 bracket reduction from five to three brackets, Renzi 2014 EUR 80 monthly bonus, Meloni 2024 three-bracket structure) over 2002-2024 produced a measurable rise in the top-10 pretax income share but a flat-to-declining top-1 share, consistent with the view that bracket-flattening compresses upper-middle-class progressivity rather than substantially benefitting the very top in a high-evasion-rate jurisdiction. The discriminating test is the divergence between top-1 and top-10 share trajectories over the period.

Falsification criterion — what would disprove this

set before the run · honoured after

This hypothesis is considered falsified if:

SUPPORTED if Italian top-10 share rises by at least 2 percentage points 2002-2024 AND top-1 share rises by less than 1 percentage point over the same window. REFUTED if both move in the same direction by more than 1 percentage point or top-1 outpaces top-10 at p<0.10.

formal test & threshold
test:      Italy descriptive time-series plus Eurozone-comparator panel of top-1 vs top-10 trajectories with bracket-count change events as breaks.

Method

Template
panel_fe
Fixed effects
country, year
Clustering
country
Sample
10 countries · 1995 – 2024
Evidence type
associational

Panel-FE with Eurozone comparator pool. Outcome top-10 minus top-1 share gap. Robustness with event_study around 2003 and 2024 breaks.

Data

VariableSourceTransform
top_1pct_pretax_income_share
outcome
owid:top-1-share-of-total-incometier 2
level
top_10pct_pretax_income_share
outcome
owid:top-10-share-of-total-incometier 2
level
ita_2003_bracket_flattening
treatment
constructed:indicator = 1 for ITA, year >= 2003tier 5
indicator
ita_2024_bracket_flattening
treatment
constructed:indicator = 1 for ITA, year >= 2024tier 5
indicator
top_marginal_income_tax_rate
treatment
owid:top-marginal-income-tax-ratetier 2
level
log_real_gdp_per_capita
control
world_bank_wdi:NY.GDP.PCAP.KDtier 2
log
trade_openness
control
world_bank_wdi:NE.TRD.GNFS.ZStier 2
level

● ready  · ● pending  · ● reconstruct-needed

Detailed result card

Result card — tax_inequality_italy_irpef_flattening_2002_2024

Verdict: INCONCLUSIVE_DATA_PENDING — treatment 'ita_2003_bracket_flattening' has no within-country variation under country fixed effects

Pre-registration

  • Claim: Italian IRPEF flattening (Berlusconi 2003 bracket reduction from five to three brackets, Renzi 2014 EUR 80 monthly bonus, Meloni 2024 three-bracket structure) over 2002-2024 produced a measurable rise in the top-10 pretax income share but a flat-to-declining top-1 share, consistent with the view that bracket-flattening compresses upper-middle-class progressivity rather than substantially benefitting the very top in a high-evasion-rate jurisdiction. The discriminating test is the divergence between top-1 and top-10 share trajectories over the period.
  • Falsification rule: SUPPORTED if Italian top-10 share rises by at least 2 percentage points 2002-2024 AND top-1 share rises by less than 1 percentage point over the same window. REFUTED if both move in the same direction by more than 1 percentage point or top-1 outpaces top-10 at p<0.10.
  • Falsification test: Italy descriptive time-series plus Eurozone-comparator panel of top-1 vs top-10 trajectories with bracket-count change events as breaks.

Estimate

  • Error: treatment 'ita_2003_bracket_flattening' has no within-country variation under country fixed effects

Variables resolved

  • owid:top-1-share-of-total-income → top_1pct_pretax_income_share (outcome, publisher=owid, n=3294)
  • owid:top-10-share-of-total-income → top_10pct_pretax_income_share (outcome, publisher=owid, n=3294)
  • constructed: indicator = 1 for ITA, year >= 2003 → ita_2003_bracket_flattening (treatment, publisher=constructed, n=300)
  • constructed: indicator = 1 for ITA, year >= 2024 → ita_2024_bracket_flattening (treatment, publisher=constructed, n=300)
  • owid:top-marginal-income-tax-rate → top_marginal_income_tax_rate (treatment, publisher=owid, n=590)
  • world_bank_wdi:NY.GDP.PCAP.KD → log_real_gdp_per_capita (controls, publisher=world_bank_wdi, n=12104)
  • world_bank_wdi:NE.TRD.GNFS.ZS → trade_openness (controls, publisher=world_bank_wdi, n=10714)

Generated by scripts/run_panel_fe.py at 2026-06-29T17:51:14+00:00

Notes

Tax-inequality candidate, swarm-S6 batch 3. The Italian pattern is well- known but rarely formalised as a hypothesis; high evasion rates limit the headline-rate elasticity at the very top.

Authored framework. Read the transparency note.