Heckman — Welfare Decomposition
Decision Accounting

Heckman — Welfare Decomposition

core
Core Claim

LATE-only evaluation misses $200–380 billion in annual welfare

The Welfare Decomposition Theorem splits any policy's welfare change into a reduced-form component (R), a structural extrapolation component (E), and a sensitivity bound (B). In five policy domains, LATE-only calibration produces an annual welfare gap of $200–380 billion.

hollow
The Hollow Win

Both design and structural camps win; the system loses

The bilateral game between design-based (Party A) and structural (Party B) econometricians produces publications and grants for both, but system welfare (System C) is excluded from the payoff space. The dominant outcome is the Hollow Win: (C=0, A=1, B=1).

exclusions
Three Structural Exclusions

LATE misses compliance types, general equilibrium, and institutional frictions

Three distinct failures make up the welfare gap: LATE only covers compliers, SUTVA rules out general equilibrium effects, and institutional frictions like deadweight loss are ignored.

theorem
Formal Theorem

Welfare decomposes into R + E + B uniquely

Under five axioms (welfare additivity, structural exclusion, bounded residual, monotonicity, institutional friction), the system welfare change ΔW = R + E + B. R is non-parametrically identified; E requires a structural model; B is a sharp bound from Manski-style bounding.

case1
Case 1: Job Corps

LATE of 0.80/hour masked age heterogeneity; 220 million/year lost

Mathematica's RCT found a statistically insignificant 0.80/hour LATE, leading to a 15% funding cut. Structural extrapolation showed +2.10/hour for ages 16–18 and -0.30/hour for ages 22–24. The cut eliminated 12,000 slots for younger participants, destroying 14.4 million in lifetime earnings annually.

case2
Case 2: UK Work Programme

Creaming and parking destroyed £480 million/year in welfare

A LATE of +3.2 percentage points in employment masked the program's creaming effect: providers selected easy-to-place clients and parked the hardest-to-place 40%, who were actively harmed (-1.8 pp). The £3.2 billion program generated a system welfare loss of £480 million/year.

case3
Case 3: Moving to Opportunity

Zero LATE on adult earnings hid $302,000 per child gain

The initial MTO evaluation found zero effect on adult earnings, leading to a 12% cut in Section 8 vouchers (150,000 vouchers eliminated). Later structural work found children who moved before age 13 gained +31% in lifetime earnings (302,000 present value). The voucher cut destroyed 21.8 billion in lifetime earnings.

case4
Case 4: Prop 47

LATE of +3.5% property crime missed $1.75 billion/year net gain

A synthetic control evaluation found a +3.5% increase in property crime, used to argue for repeal. Structural extrapolation showed the 13,000 released inmates generated 1.1 billion/year in avoided incarceration costs plus 650 million/year in family stabilization gains. Net system welfare: +$1.75 billion/year.

change
Game Change

Mandate the (R, E, B) vector as the standard reporting template

The remedy is institutional: journal editors and grant agency directors must require the Welfare Decomposition (R, E, B) in place of LATE-only reporting. This moves system welfare into the academic payoff space, breaking the Hollow Win equilibrium.

impact
What It Changes

Policy evaluation shifts from extractive to welfare-optimizing

The (R, E, B) template forces every evaluation to report an identification-robust floor, a structural extrapolation, and a bound on residual uncertainty. This ends the practice of treating a LATE as a comprehensive welfare parameter and aligns incentives with system welfare.