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V1.3 Case Page #10 (Negative Exhibit)

United States (1918–1919): School Closures with Precise Null Long-Run Effects (V1.3)

Case Claim (one-line)

Rigorous evidence using city-level school closure timing during the 1918–1919 influenza pandemic finds no detectable long-run effects of 1918 school closures on adult educational attainment and labor-market outcomes—showing that not every interruption becomes an education pipeline rupture. (direct.mit.edu)

Start Here:

1) Case Facts (dated, minimal)

  • Time window: 1918–1919 influenza pandemic (United States). (NBER)
  • Policy exposure: Many cities closed schools; researchers compiled exact timing for 168 cities. (NBER)
  • Key empirical result: Using newly collected closure timing and linking affected children to adult outcomes (e.g., 1940 census), the study reports precise null effects on:
  • school attendance in 1919–20, and
  • adult educational attainment and multiple labor-market outcomes. (direct.mit.edu)

This is not “school closures were harmless” as a slogan.
This is a negative exhibit: closure alone is not sufficient for rupture.

2) Rupture Mechanism Test (EduKateOS / CivOS lattice mapping)

This case is a failure-to-rupture case. We map it to the same lattice and ask: Why didn’t P0 lock in?

Z0 — Stabilisation time loss (present, but not decisive)

Closures reduce instruction time, but the evidence implies the net stabilisation loss did not translate into measurable long-run attainment loss at population scale in this setting. (direct.mit.edu)

Z0 implication: time loss can be absorbed if buffers and verification are sufficient.

Z1 — Household buffering likely mattered (and was uneven)

V1.3 does not claim all households buffer equally. It claims that a system avoids rupture if enough buffering exists to prevent cohort-level Phase collapse.

This negative exhibit implies the combination of:

  • household buffering,
  • local adaptations,
  • and institutional catch-up,
    was sufficient to prevent long-run attainment loss detectable in the linked data.

(You don’t need to over-interpret mechanisms; the core is the null result.)

Z2 — Institutional recovery capacity (rapid re-lock)

The result implies that:

  • institutions resumed,
  • and the system re-locked its education pipeline before the cohort deficit became permanent.

Z2 implication: recovery capacity and verification can prevent corridor lock-in even after a shock.

Z3 — No measurable delayed capability signal (by the chosen outcomes)

The study explicitly reports null effects on adult education and economic outcomes for exposed cohorts. (NBER)

Z3 implication: the pipeline did not fall below replacement in a way that showed up in long-run cohort outcomes (under this identification strategy).

3) Irreversibility Signature (absent)

In rupture cases, we see:

  • persistent cohort deficit
  • intergenerational propagation
  • long recovery constants

Here, the defining feature is the opposite:

the long-run cohort deficit is not detectable. (direct.mit.edu)

This matters. It forces the model to be falsifiable.

4) General Law (portable, predictive)

Interruption-Only Is Not a Rupture Law:
School interruption is a risk factor, not a guaranteed rupture. A pipeline ruptures (P0 locks in) only when interruption combines with insufficient buffering and insufficient institutional re-lock—i.e., when the system cannot restore Z0 stabilisation and Z2 verification before cohort drift becomes permanent.

This is why the V1.3 triad includes “mode” and “mechanism,” not just “shock.”

5) Exhibits (sources)

  • Ager et al. (NBER working paper): “School Closures during the 1918 Flu Pandemic” — finds precise null long-run effects on education and labor outcomes, using closure timing across 168 cities and linkage to adult outcomes. (NBER)
  • Published version (Review of Economics and Statistics): reports no detectable impact on educational attainment and adult outcomes. (direct.mit.edu)

Standard Bridge Block (Bukit Timah → New York → Planetary)

This negative exhibit is essential for corridor prediction: it prevents lazy alarmism. It forces the real question to become:

When does a disruption become a corridor?
Answer: when stabilisation loss combines with thinning household buffers (Z1) and degraded institutional verification (Z2), such that replacement falls below threshold.

That is the exact distinction BukitTimahTutor.com will formalise: not “stress exists,” but whether the system is still regenerative.

Index Update (add Case #10)

Add to the hub page Case Index:

  • Case 10 — US 1918–1919: school closures with precise null long-run effects (negative exhibit). (direct.mit.edu)

If you say next again, I’ll continue stepping back with another pair of courtroom exhibits, and I’ll keep mixing:

  • rupture exhibits (positive cases), and
  • negative exhibits (null / partial cases),

so the lattice becomes a real diagnostic instrument rather than a narrative.

Start Here for our Ministry of Education Series (CivOS/EducationOS Grade)

BukitTimahTutor Lattice Graph Block

Z0 Execution:
BTT.MAT.Z0.P.ALG.001
BTT.MAT.Z0.P.DIF.001
BTT.SEN.Z0.S.TTC.001
BTT.MAT.Z0.S.ERR.001

Z1 Support Loops:
BTT.PAR.Z1.P.HOM.001
BTT.TUI.Z1.P.SCF.001
BTT.SEN.Z1.S.DEP.001
BTT.SEN.Z1.S.FCG.001

Z2 Exam/Transition:
BTT.EXM.Z2.P.SEC.001
BTT.EDU.Z2.P.TRN.001
BTT.EXM.Z2.B.OLEV.001

Z3 Interfaces:
SG.EDU.Z3.B.SYL.001
SG.EDU.Z3.B.EXM.001
SG.EDU.Z3.B.PLC.001

Edges:
BTT.TUI.Z1.P.SCF.001 BindsTo BTT.MAT.Z0.P.ALG.001
BTT.MAT.Z0.P.ALG.001 BindsTo BTT.EXM.Z2.P.SEC.001
BTT.EDU.Z2.P.TRN.001 Impacts BTT.EXM.Z2.B.OLEV.001
BTT.SEN.Z1.S.DEP.001 Impacts BTT.EXM.Z2.P.SEC.001
BTT.SEN.Z0.S.TTC.001 Observes BTT.EXM.Z2.P.SEC.001