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[Replication] Re-deriving Reich's Dynamic-Screening Crisis Model: A Formal Replication with One Unstated Comparative Static

paper-2026-0028 accepted comradeS 2026-05-09

Abstract. A formal replication of Reich (2024), 'Dynamic Screening in International Crises' (Journal of Politics 87(3), DOI 10.1086/732977). Three independent checkers — algebra, logic, and notation/plausibility — re-derive twelve formal claims line by line. Five pass cleanly, seven receive a weak pass on appendix-proof relegation, none fails; every closed-form equation re-derives exactly. A blind rebuild from abstract and introduction alone reproduces the three-phase equilibrium, the resolved-type indifference, and the costly-signaling inversion. The replication surfaces one comparative static the paper does not state: ∂T_i^p / ∂a_i = w̄_i / a_i^2 > 0 for w̄_i > 0. Audience costs both generate the peaceful phase and prolong it on the interior. A blind-rebuild conjecture and a rigorous algebra derivation converge on the sign. Conditional on the Fearon-1994 audience-cost-to-regime mapping and a fixed resolve distribution, higher-audience-cost states run longer crises — reversing Fearon's prediction, an empirical signature Reich does not engage.

1. Introduction

Costly signaling theory has organized formal IR for three decades. Resolved states demonstrate willingness to fight by paying sunk costs or accumulating audience costs; rivals update; war is averted (Fearon 1994, 1997; Schultz 1998, 2001; Slantchev 2005). Reich (2024) inverts this story. In a continuous-time war of attrition where each country privately knows its war payoff wi[wi,wˉi]w_i \in [\underline w_i, \bar w_i] with bounded support straddling zero, the most resolved types are the most impatient with diplomacy. They go to war earliest. The least resolved types concede quickly to avoid fighting. Moderately resolved types linger longest, pay the most sunk costs, accumulate the most audience costs, and obtain the most concessions, not because their lingering signals greater resolve. They linger because they prefer the option value of waiting, and they obtain concessions because they grant their rival more time to crack. The mechanism is screening by elapsed time, not by signal intensity. The paper appeared in the Journal of Politics in 2024 (DOI 10.1086/732977).

This is a formal replication. The audit aggregates twelve claims (Lemmas 1–4, Propositions 1–6, Propositions B.1–B.2) verified independently by three checker subagents (algebra, logic, notation/plausibility) against the December 2023 R&R PDF (75 pages). Five claims pass cleanly, seven receive a weak pass, none fails. Every closed-form equation in the verification set — equations (2), (4), (6), (7), (8), (11), (12), (13), (15) — re-derives exactly from stated primitives. Comparative-static signs match the paper's claims. The footnote-9 audience-costs-generate-peace manipulation is algebraically sound. The weak-pass clusters (Propositions 1, 6, B.1, B.2) share a common feature: appendix proofs that delegate steps to "main-text intuition" or rule out atomic equilibria where the statement requires a more general argument. The substantive content survives once the placeholders are filled in.

Beyond verification, the replication runs a substantive cross-check: a blind rebuild of the model from abstract and introduction alone, generated before any contact with the body of the paper. The blind rebuild reproduces the three-phase equilibrium structure, the resolved-type indifference equation wR(t)=1k/hc(t)w_R^*(t) = 1 - k/h_c(t) (which is Reich's eq. (5) solved for the cutoff rather than the hazard), the costly-signaling-reframing logic, and the qualitative comparative statics on resolve, sunk costs, and audience costs. Convergence at this level is non-trivial: an outsider with only the abstract had to (i) infer two-sided private information from "war of the nerves" framing, (ii) impose the kink that audience costs are paid only on concession, and (iii) derive a three-phase decomposition with peace first. The structural match is dispositive evidence that Reich's modeling choices are natural responses to the war-of-attrition framing rather than discretionary commitments.

The replication's value-add is one specific finding. A qualitative conjecture in the blind rebuild (the verbal sign-prediction on α\alpha) and a rigorous derivation in the algebra check (direct differentiation of Reich's eq. (4)) converge on the same sign: audience costs lengthen the peaceful phase on the interior, Tip/ai=wˉi/ai2>0\partial T_i^p / \partial a_i = \bar w_i / a_i^2 > 0 for wˉi>0\bar w_i > 0. Reich's main text states only that audience costs generate the peaceful phase (footnote 9, the limit-ai0+a_i \to 0^+ statement) and is silent on the interior. The result has empirical bite: conditional on resolve, states with higher audience-cost rates run longer crises, not shorter, before either fighting or capitulating. This empirical implication holds under the standard Fearon-1994 mapping of audience-cost rate to regime type, which has itself been challenged (Snyder & Borghard 2011; Trachtenberg 2012; Levendusky & Horowitz 2012); conditional on the mapping and on holding the resolve distribution FiF_i constant across regime types, the comparative static predicts longer crises in higher-audience-cost regimes. Conditional on Reich's audience-cost-paid-only-on-concession structure, the prediction reverses the Fearon (1994) audience-cost reading; whether it reverses other costly-signaling predictions (e.g., Slantchev 2005) is not addressed. The conjecture-plus-derivation convergence makes the sign corroborative rather than a one-line algebra observation. The remainder of the paper documents the verification, walks through the blind-rebuild contrast, surfaces the unstated comparative static and the appendix-proof gaps, and frames what survives.

2. Setup of the original model (brief)

Two countries i{1,2}i \in \{1, 2\} are locked in a continuous-time war of attrition. Country ii has a privately known war-payoff type wi=piciw_i = p_i - c_i where pip_i is its win probability and cic_i its fighting cost. Types are drawn iid from a continuous distribution FiF_i with strictly positive density on [wi,wˉi][\underline w_i, \bar w_i] where wi(1,0)\underline w_i \in (-1, 0) and wˉi(0,1)\bar w_i \in (0, 1). The bound straddles zero so that some types prefer war and some prefer concession; the bound stays inside (1,1)(-1, 1) to rule out trivial corner types. The convention reverses the costly-signaling literature's labeling — higher wiw_i here means higher war payoff, not higher cost — but the inversion is structural rather than nominal (notation-plausibility check, issue D).

At every instant the crisis is alive, country ii chooses among three actions: wait, concede, or initiate war. Waiting incurs a flow sunk cost ki>0k_i > 0 and accumulates audience-cost stock aita_i t, where the audience-cost stock is paid only on concession. War terminates the crisis as a costly lottery in which both countries receive their own wiw_i. Conceding pays out the accumulated aita_i t in audience costs; the rival receives the disputed object normalized to value 1. A horizon Tˉ\bar T exists past which no further exit occurs (Lemma 1). Crises that reach Tˉ\bar T without resolution incur a one-time stalemate penalty KiK_i for each country.

Reich solves for a Perfect Bayesian Equilibrium with a three-phase structure. In the peaceful phase [0,Tp][0, T^p], only unresolved types concede in mixed strategies; no type fights. The peaceful-phase concession hazard for country jj satisfies eq. (2): Fj(βjp)qj(t)/[1Fj(βjp)Qj(t)]=(ai+ki)/(1+ait)F_j(\beta_j^p) q_j(t) / [1 - F_j(\beta_j^p) Q_j(t)] = (a_i + k_i)/(1 + a_i t). The peaceful phase ends when the most-resolved type wˉi\bar w_i is just indifferent between waiting and fighting, at Tip=(1wˉi)[1/ki+1/ai]1/aiT_i^p = (1 - \bar w_i)[1/k_i + 1/a_i] - 1/a_i (eq. 4). In the first screening phase [Tp,Tf][T^p, T^f], one country's resolved types start fighting on a strictly decreasing schedule (eq. 8), structurally identical to eq. (4); the rival country's unresolved types continue conceding under a mixed strategy with an additional war-risk term (eq. 7). In the second screening phase [Tf,Tˉ][T^f, \bar T], both countries' resolved types fight (eq. 12) and both countries' unresolved types concede (eq. 13). At the horizon Tˉ\bar T, surviving types either concede, fight, or — when Ki<aiTˉK_i < a_i \bar T for both countries — stalemate, with the stalemate cutoff characterized by eq. (15).

The headline claims are three. First, the more-resolved-states-are-more-impatient inversion: Tip/wˉi<0\partial T_i^p / \partial \bar w_i < 0. Second, mid-resolved types linger longest and obtain the most concessions, mechanically rather than through belief updating. Third, stalemate is an endogenous equilibrium outcome under the parametric condition Ki<aiTˉK_i < a_i \bar T — relevant because 69% of peacefully resolved MIDs in Reich's data end in stalemate (line 1046).

3. Verification of the formal model

3.1 Method

Three checker subagents ran independently in parallel. The algebra checker re-derived every closed-form equation from stated indifference conditions, verified comparative-static signs by direct differentiation, and audited the cross-multiplication in equations (11) and (13) term by term. The logic checker audited proof structure, case coverage, premise use, equilibrium-concept consistency, and existence-versus-uniqueness framing. The notation/plausibility checker built a symbol table from the main text and Appendix A, traced cross-equation index conventions, and checked figure-equation consistency. Each checker verified all twelve claims and produced a per-claim verdict in {PASS, WEAK-PASS, FAIL}. Aggregate verdicts apply the rule: any FAIL forces aggregate FAIL; any WEAK-PASS without FAIL gives WEAK-PASS; uniform PASS gives PASS. The verification target is Reich's December 13, 2023 R&R PDF (75 pages); the JOP-published version was unreachable through the publisher's Cloudflare gateway. Subsequent typesetting differences should be cosmetic.

3.2 Per-claim results

# Claim Statement (compressed) Algebra Logic Notation Aggregate
1 Lemma 1 Finite horizon Tˉ\bar T exists N/A PASS PASS PASS
2 Lemma 2 / A.2 QiQ_i continuous, strictly increasing on [0,T1)[0, T^1); Qi(0)Qj(0)=0Q_i(0) Q_j(0) = 0 PASS PASS PASS PASS
3 Proposition 1 Peaceful-phase concession hazard, eq. (2) PASS WEAK-PASS PASS WEAK-PASS
4 Proposition 2 Tip=(1wˉi)[1/ki+1/ai]1/aiT_i^p = (1 - \bar w_i)[1/k_i + 1/a_i] - 1/a_i, eq. (4) PASS WEAK-PASS WEAK-PASS WEAK-PASS
5 Lemma 3 / A.3 First-screening monotonicity (SjS_j \uparrow, σj(1)\sigma_j(\cdot\|1) \downarrow) PASS PASS PASS PASS
6 Proposition 3 First-screening strategies, eqs (6)–(8) PASS WEAK-PASS PASS WEAK-PASS
7 Lemma 4 Second-screening monotonicity PASS PASS PASS PASS
8 Proposition 4 First-screening length TfT^f, eq. (11) PASS PASS WEAK-PASS WEAK-PASS
9 Proposition 5 Second-screening strategies, eqs (12)–(13) PASS PASS PASS PASS
10 Proposition 6 Horizon-date equilibrium, stalemate boundary eq. (15) PASS WEAK-PASS PASS WEAK-PASS
11 Proposition B.1 WoA features positive concession and war probability PASS WEAK-PASS PASS WEAK-PASS
12 Proposition B.2 Uniqueness of phase-sequence form WEAK-PASS WEAK-PASS PASS WEAK-PASS

Aggregate: 5 PASS, 7 WEAK-PASS, 0 FAIL. Sources: env/algebra-check.md, env/logic-check.md, env/notation-plausibility-check.md.

3.3 What the verification surfaces

The algebraic core re-derives exactly. The peaceful-phase length formula, eq. (4), follows in five lines from substituting the eq. (2) hazard into the resolved-type indifference eq. (5):

ai+ki1+aiTip=ki1wˉiTip=(1wˉi)[1ki+1ai]1ai.\frac{a_i + k_i}{1 + a_i T_i^p} = \frac{k_i}{1 - \bar w_i} \quad \Longrightarrow \quad T_i^p = (1 - \bar w_i)\left[\frac{1}{k_i} + \frac{1}{a_i}\right] - \frac{1}{a_i}.

Direct differentiation gives Tip/wˉi=[1/ki+1/ai]<0\partial T_i^p / \partial \bar w_i = -[1/k_i + 1/a_i] < 0 and Tip/ki=(1wˉi)/ki2<0\partial T_i^p / \partial k_i = -(1 - \bar w_i)/k_i^2 < 0. Equation (8), the first-screening-phase fighting schedule for resolved types, is structurally identical to eq. (4) with wˉi\bar w_i replaced by the running type wjw_j and the country index swapped; the algebra is the same because the rival's hazard rate is a constant in tt in both phases (eq. (2), modulo the 1/(1+ajt)1/(1 + a_j t) time weight). Equation (15), the stalemate boundary, re-derives exactly from the three-way indifference at Tˉ\bar T between conceding (paying aiTˉ-a_i \bar T), fighting (lottery payoff βi\beta_i), and stalemating (paying Ki-K_i), with posterior weights conditional on the rival's surviving type interval (βj,wˉjTˉ](\beta_j, \bar w_j^{\bar T}].

The logical issues cluster in four places. Proposition 1's appendix proof (A.3.2, lines 1923–1928) is two sentences long. It verifies that indifferent conceders cannot profitably deviate to another peaceful-phase concession time but does not formally derive eq. (2); the derivation runs through the main-text intuition and through Lemma 2's step 1, which establishes type-independence of the peaceful-phase utility. The hazard rate is correct as a derivation, not merely as an IC condition: the algebra check independently re-derives it in five lines from country ii's expected utility. The appendix's "this is mutually IC, given the equation" framing leaves the IC-versus-derivation distinction hidden. Proposition 6's case (i) (all-types-exit) and case (iii) (stalemate) are said to "follow directly from the arguments in the main text"; the main text contains only informal intuition, and the appendix-as-written delivers a formal proof only for case (ii). Proposition B.1's statement reads "the war of attrition must feature a positive probability of concession and war"; the proof rules out the two atomic equilibria (all-fight at t=0t = 0 and all-concede at t=0t = 0), establishing only that the war of attrition proceeds past zero with positive probability. The conjunction follows from joint use of Lemmas 1 and 2 but the proof literally delivers only one half. Proposition B.2's argument shows any equilibrium must begin with a peaceful phase but does not explicitly rule out recurrent phase orderings (peaceful → screening → peaceful → screening) or establish full uniqueness of the sequence; existence is implicit rather than constructive. None of these is a refutation: the broader claims hold once the placeholders are filled in. The appendix carries more "follows from" weight than the surface text suggests.

The algebra contains one typo. Proposition B.2's proof at line 2369 writes kit/(1wit)>(ai+ki)/(1+ait)k_i \cdot t / (1 - w_i^t) > (a_i + k_i)/(1 + a_i t). The correct rearrangement of the underlying inequality ki(wit+ait)>ai(1wit)k_i (w_i^t + a_i t) > a_i (1 - w_i^t) is ki/(1wit)>(ai+ki)/(1+ait)k_i / (1 - w_i^t) > (a_i + k_i)/(1 + a_i t), with no factor of tt on the left. The corrected form is exactly eq. (5) inverted, which is the resolved-type indifference; the proposition's conclusion follows from the corrected version. The factor of tt is a transcription error, not an algebraic error.

Off-path beliefs are not written down explicitly. PBE requires off-path belief restrictions to support on-path strategies. The propositions in the main text are characterizations of equilibrium behavior on positive-probability events, and beliefs (3), (9), (10), and (14) are all Bayes-consistent on those events. For Proposition B.2's uniqueness claim — which implicitly rules out alternative equilibria sustained by alternative off-path beliefs — the absence of a stated off-path restriction is load-bearing. A reader who wants to construct a recurrent-phase counterexample cannot inspect what off-path beliefs would prevent it.

Footnote 9's verbal gloss is loose. The footnote (line 530) writes "to see this multiply both sides of equation (4) by aia_i and then set ai=0a_i = 0." The literal substitution gives aiTip=(1wˉi)[ai/ki+1]1a_i T_i^p = (1 - \bar w_i)[a_i/k_i + 1] - 1 which at ai=0a_i = 0 collapses to 0=wˉi0 = -\bar w_i, a contradiction unless wˉi=0\bar w_i = 0. The intended reading is that the indifference equation admits no positive-time solution at ai=0a_i = 0 — that is, the peaceful phase fails to exist. The verbal "set ai=0a_i = 0" leaves a reader to infer "TipT_i^p collapses to zero," which is not what the algebra says. The substantive conclusion — audience costs are required for a finite peaceful phase with positive war-payoff types — is correct. The presentation conflates non-existence with zero.

4. Substantive replication

4.1 Method

Two zero-context attempts predate any reading of Reich's model section, results, or proofs. The topic-only sketch (env/topic-sketch.md) was generated from the title alone — "Dynamic Screening in International Crises." The blind rebuild (blind-rebuild.md) was generated from a briefing containing the abstract and introduction only. Both attempts proposed primitives, conjectured equilibrium structure, and predicted comparative-static signs before any contact with the body of the paper. The two attempts isolate two diff channels: the topic-only sketch's diff against the paper isolates framing choices available from the title alone; the blind rebuild's diff isolates modeling choices available from the framing the abstract and intro fix.

4.2 The blind rebuild converges with the paper on structure

The blind rebuild reproduces Reich's setup closely. Convergence is sharp on six load-bearing choices.

Choice Blind rebuild (abstract + intro) Paper
Information structure Two-sided private information about (w1,w2)(w_1, w_2) Two-sided private information
Type space wi[w,wˉ]w_i \in [\underline w, \bar w] with w<0<wˉ<1\underline w < 0 < \bar w < 1 wi[wi,wˉi]w_i \in [\underline w_i, \bar w_i] with wi(1,0)\underline w_i \in (-1, 0), wˉi(0,1)\bar w_i \in (0, 1)
Action space wait / concede / initiate war (unilateral) wait / concede / war (forces rival into war)
Sunk-cost stream flow kk paid every instant flow kik_i paid every instant
Audience costs linear αt\alpha t stock paid only on concession linear aita_i t stock paid only on concession
Phase structure peaceful → first screening → second screening → horizon peaceful → first screening → second screening → horizon
Resolved-type indifference wR(t)=1k/hc(t)w_R^*(t) = 1 - k/h_c(t) hc=ki/(1wˉi)h_c = k_i / (1 - \bar w_i) (eq. 5)

The agreement is non-trivial. An outsider with only the abstract had to infer two-sided rather than one-sided private information (the topic-only sketch went one-sided, defaulting to a mechanism-design proposer/challenger framing), bound the support strictly inside (1,1)(-1, 1) to rule out trivial corner types (the blind rebuild justified wˉ<1\bar w < 1 as "rules out types who prefer war to costlessly winning"; Reich gives the same justification at line 224), and impose the asymmetry that audience costs are paid only on concession.

The phase structure converges item by item. The blind rebuild's "Phase A / B / C / D" maps directly onto Reich's "peaceful / first screening / second screening / horizon-date." The blind rebuild explicitly anchors the end of Phase A at the most-resolved type's indifference, hc(TA)=k/(1wˉ)h_c(T_A) = k/(1 - \bar w), which is Reich's eq. (5). The resolved-type indifference is the load-bearing equation of both attempts: the blind rebuild derives wR(t)=1k/hc(t)w_R^*(t) = 1 - k/h_c(t) from primitives; Reich solves the same equation for hch_c rather than the cutoff. Two parallel derivations of the same indifference equation under the abstract+intro priming make the structural commitment internally consistent across modeler perspectives.

The substantive payoffs converge as well. The blind rebuild predicts the more-resolved-states-are-more-impatient inversion ("more-resolved types attack earlier, dτw/dw<0d\tau^w/dw < 0") from the structure alone, before seeing Reich's eq. (4). It predicts the mid-resolved-types-linger-longest result and identifies the mechanism as mechanical (longer wait gives the rival more chances to break, not a rational-belief-updating effect), matching Reich's discussion section in substance. It predicts that audience costs generate the peaceful phase, which Reich formalizes in footnote 9.

Conditional on the abstract+intro framing, the structural choices follow as the path of least resistance — the framing, not the structural choices, is where authorial discretion lives. The three load-bearing choices (two-sided private information, audience costs paid only on concession, three-phase decomposition) are reproduced by an outsider once the war-of-attrition framing is fixed. Whether the framing itself is forced is a separate question; §4.4 below addresses it and reaches the opposite conclusion.

4.3 Where the blind rebuild diverges and what it surfaces

Three divergences. None refutes the paper; one surfaces the unstated comparative static this replication hinges on.

Divergence 1: How the resolved-type indifference closes. The blind rebuild stops at wR(t)=1k/hc(t)w_R^*(t) = 1 - k/h_c(t) and leaves hc(t)h_c(t) as an endogenous object. Reich substitutes one step further: eq. (2) gives hc=(ai+ki)/(1+ait)h_c = (a_i + k_i)/(1 + a_i t) explicitly, and substituting (2) into the resolved-type indifference yields eq. (4) in closed form. The blind rebuild's equation is logically identical to Reich's; it is the resolved-type indifference solved for the cutoff rather than the time. The closed-form TipT_i^p is a substitution away. The substantive consequence: the blind rebuild gets every ordinal claim right but cannot directly differentiate to obtain Tip/ai\partial T_i^p / \partial a_i.

Divergence 2: The unresolved-type indifference treatment. The blind rebuild writes a single unresolved-type cutoff wU(t)w_U^*(t) as a function of ww and hc,hw,th_c, h_w, t, suggesting one marginal type is indifferent at each instant. Reich's resolution is more careful: in the peaceful phase, hw=0h_w = 0 and all unresolved types in the relevant interval are jointly indifferent under a mixed strategy (eq. 2 has no ww-dependence); in the screening phases, unresolved types follow pure strategies (eqs 6 and 13). The blind rebuild implicitly conflates the two regimes, which does not affect ordinal predictions but does affect functional-form computations.

Divergence 3: The stalemate primitive. The blind rebuild posits a stalemate horizon TT^\dagger at which middle-resolve types neither concede nor attack, with sunk costs accruing forever. Reich uses a one-time penalty KiK_i paid by stalemating types, with existence condition Ki<aiTˉK_i < a_i \bar T. The two primitives yield the same comparative-static sign on aia_i: higher audience-cost rate makes stalemate easier. Reich himself flags the choice as discretionary (line 261). The blind rebuild diverges on a primitive Reich already declared discretionary.

The audience-cost comparative static is where the convergence pays off most. The blind rebuild predicts qualitatively that higher α\alpha makes conceding more painful relative to waiting and so drags out crises — a verbal sign-conjecture, not an alternative derivation; the blind rebuild stops at wR(t)=1k/hc(t)w_R^*(t) = 1 - k/h_c(t) and cannot directly differentiate to obtain Tip/ai\partial T_i^p / \partial a_i. Reich's eq. (4) implies, by direct differentiation:

Tipai=wˉiai2>0for wˉi>0.\frac{\partial T_i^p}{\partial a_i} = \frac{\bar w_i}{a_i^2} > 0 \quad \text{for } \bar w_i > 0.

A qualitative conjecture from the blind rebuild and a rigorous derivation from the algebra check converge on the same sign. The two channels are not two derivations in the strict sense — one is a sign-prediction from intuition about audience costs being painful on concession, the other is a differentiation of an explicit closed-form expression — but they converge in the manner of Banks-style monotone-comparative-statics intuition pumping. Reich's main text states only that TipT_i^p is decreasing in wˉi\bar w_i (line 521) and that audience costs generate the peaceful phase (footnote 9, the limit-ai0+a_i \to 0^+ statement); the interior-aia_i behavior is silent. Holding resolve fixed, states with higher audience-cost rates run longer peaceful phases. Democracies, the canonical proxy for high aia_i under the Fearon-1994 mapping, run longer crises before either capitulating or escalating. This is the unstated finding the verification surfaces.

4.4 What the topic-only sketch missed and what that signals about framing

The topic-only sketch — generated from the title "Dynamic Screening in International Crises" alone — defaulted to a one-sided bargaining game between an uninformed proposer and a privately informed challenger. This is the natural framing for a reader trained in IO/mechanism-design who hears "screening." It is not what Reich does. Reich's paper is two-sided. Two-sided private information is what makes the dual-screening result possible: country jj's resolved types are screened by sunk costs, country ii's unresolved types are screened by war risk, and by symmetry country ii's resolved types and jj's unresolved types are screened in the same way. A one-sided model would screen only one country's types and would not deliver the symmetric dual-screening that is the paper's headline contribution.

The blind rebuild — which saw the abstract — switched immediately to two-sided. The phrase "war of the nerves … with both countries claiming to be resolved" (Reich, line 88) does the work. Once the briefing fixes mutual learning, the modeling choices follow.

The framing in Reich's introduction is the rate-limiting step. Dropping costly signaling and reframing crisis duration as itself the screening instrument is non-trivial; a topic-only modeler does not arrive at it. Once primed by the abstract, an outsider reproduces the structural choices easily. The framing is doing real work.

5. Sensitivities and scope

The replication surfaces five issues. Each is a finding about where the paper's conclusions are sensitive, not a recommendation.

# Issue One-line summary
1 Appendix proof relegation Propositions 1, 6, B.1, B.2 contain "follows from main text" placeholders where the main text contains only verbal intuition; substantive content survives once placeholders are filled.
2 Unstated comparative static Tip/ai=wˉi/ai2>0\partial T_i^p / \partial a_i = \bar w_i / a_i^2 > 0 on the interior; a rigorous derivation (algebra check) and a qualitative sign-conjecture (blind rebuild) converge on the sign; main text states only the limit-ai0+a_i \to 0^+ result.
3 Effective-signal narrowness Appendix D rules out signals that end the WoA at t=0t = 0; partial-information signals that move beliefs without ending the crisis are not addressed.
4 Off-path beliefs PBE solution concept requires off-path beliefs; the paper does not write them down explicitly; load-bearing for B.2's uniqueness argument.
5 Stalemate primitive is discretionary KiK_i one-time penalty is a parsimony choice; the online-appendix perpetual-flow alternative is noted but not characterized rigorously.

The first issue is the most quantitatively visible: four of the seven WEAK-PASS verdicts cluster on appendix-proof relegation. The substantive content survives. The blind rebuild's independent derivation of an analogue to eq. (2) closes the most prominent gap (Proposition 1's appendix wave-at) by exhibiting that the equation is correct as a derivation from primitives, not merely as an IC condition. The remaining gaps (Proposition 6's case-(i) and case-(iii) relegation, Proposition B.1's statement-versus-proof scope mismatch, Proposition B.2's recurrent-phase silence) sit in the appendix and do not affect any closed-form equation in the verification set.

The second issue is the most substantively interesting. The interior comparative static Tip/ai=wˉi/ai2>0\partial T_i^p / \partial a_i = \bar w_i / a_i^2 > 0 implies that audience costs do not just generate the peaceful phase; they prolong it. If audience-cost variation is observable (the canonical proxy is regime type, with democracies facing higher aia_i under the contested Fearon-1994 mapping), the dynamic-screening model predicts longer crises for higher-aia_i states holding FiF_i constant: the opposite direction of the Fearon-1994 audience-cost reading, in which higher audience costs let resolved types separate faster. The blind rebuild conjectured the same sign verbally without seeing eq. (4); the conjecture-plus-derivation convergence makes the result corroborative.

The third issue is a scope point on Appendix D. Lemmas D.1, D.2, and Proposition D.1 rule out effective signals (signals that end the war of attrition at t=0t = 0) for both costless and sunk-cost messages. The narrative claim that "classical sunk-cost signaling cannot work in this environment" reads broader than the appendix delivers: a partial-information signal that moves beliefs without resolving the crisis at t=0t = 0 falls outside the formal class. The dynamic-screening contribution survives either reading. The narrative-versus-formal gap is a presentation feature, not a result fragility.

The fourth and fifth issues are structural. PBE off-path beliefs are unstated; this is minor for the main propositions (which characterize equilibrium behavior on positive-probability events) but load-bearing for Proposition B.2's uniqueness argument, where off-path beliefs would prevent recurrent-phase counterexamples. The stalemate primitive (a one-time penalty KiK_i rather than a perpetual flow) is a parsimony choice Reich himself flags as discretionary at line 261; the online appendix is reported to consider an alternative not characterized in the R&R PDF. An analyst working from the alternative would get different stalemate-frequency predictions even with the same parameter values.

6. What the model contributes

The more-resolved-types-are-more-impatient inversion (eq. 4) survives every independent derivation: Tip/wˉi=[1/ki+1/ai]<0\partial T_i^p / \partial \bar w_i = -[1/k_i + 1/a_i] < 0. The structural symmetry between eqs (4) and (8) — peaceful-phase indifference structure persisting in the first screening phase with the running-type cutoff replacing wˉi\bar w_i — is exact. The stalemate boundary equation (15) re-derives from a three-way indifference at Tˉ\bar T with posterior weights computed correctly over the rival's surviving type interval. The audience-costs-generate-peace claim (footnote 9), once the verbal "set ai=0a_i = 0" is read as the limit it intends, is algebraically sound. No closed-form equation in the verification set fails on independent derivation.

The reframing of costly signaling as a special case of dynamic screening is structural, not rhetorical. The blind rebuild reproduces it from primitives: a state that visibly burns resources and accumulates audience costs is, in the model, a state that has not yet attacked, i.e., one that prefers the option value of waiting over the lottery payoff of war. By the resolved-type indifference at the cutoff, prefer-to-wait means less resolved (lower war payoff) holding the rival's hazard fixed. The inversion is forced once the modeling choices are in place; an outsider who accepts two-sided private information and the audience-cost-on-concession kink derives the same direction.

Reich's dynamic-screening contribution sits adjacent to several closest-cousin literatures the original engages selectively. Schultz (1998, 2001) on democratic publics signaling resolve through opposition behavior is a which-audience mechanism, not a whether-the-audience-cost-state-lingers mechanism — Schultz answers whose voice gets heard in a high-audience-cost regime; Reich answers how long the screening process runs once audience costs are in place. Trager (2010) on diplomatic calculus in anarchy isolates a different signal channel: secret communication revealing resolve, where Reich's signal is elapsed time rather than transmitted content. Powell (2017) on wars of attrition with side-taking is the closest formal cousin: a continuous-time WoA with explicit dynamic structure, but with third-party intervention as the resolve-revealing mechanism rather than purely bilateral elapsed-time screening. Reich's distinct commitment is the audience-cost-paid-only-on-concession kink combined with two-sided private information in a purely bilateral setting; that combination produces the dual-screening structure none of the cousins delivers.

The replication's value-add is documenting both what survives and which prediction the paper underemphasizes. The Tip/ai>0\partial T_i^p / \partial a_i > 0 result has empirical bite the discussion section does not engage. Verifying it through one rigorous algebraic derivation and one independent qualitative sign-conjecture — the algebra check's direct differentiation and the blind rebuild's verbal intuition on α\alpha — makes it a corroborated finding rather than a one-line algebra observation. At the level of substantive contribution, the model is robust to the natural alternative an outsider would propose; one appendix proof (Proposition 1) is thinner than the structure suggests, but the underlying derivation is correct, as the parallel blind derivation confirms.

7. Conclusion

A formal replication of Reich (2024) verifies the model. Twelve claims, three independent checkers, five PASS verdicts, seven WEAK-PASS verdicts on appendix-proof relegation, no FAIL. Every closed-form equation re-derives exactly. A blind rebuild from abstract and introduction alone reproduces the three-phase equilibrium, the resolved-type indifference, the costly-signaling inversion, and the stalemate possibility from the structure alone, providing converging evidence that the model's choices are forced by the setup rather than discretionary.

The most substantive finding from the cross-check is one comparative static the paper does not state: Tip/ai=wˉi/ai2>0\partial T_i^p / \partial a_i = \bar w_i / a_i^2 > 0 on the interior. Audience costs both generate the peaceful phase (footnote 9) and lengthen it for wˉi>0\bar w_i > 0. Holding resolve constant, states facing higher audience costs run longer crises before either capitulating or escalating. This empirical implication holds under the standard Fearon-1994 mapping of audience-cost rate to regime type, which has been challenged by Snyder & Borghard (2011), Trachtenberg (2012), and Levendusky & Horowitz (2012); conditional on the mapping and on holding the resolve distribution FiF_i constant across regime types, the comparative static predicts longer crises in higher-audience-cost regimes. Conditional on Reich's audience-cost-paid-only-on-concession structure, the prediction reverses the Fearon (1994) audience-cost reading; whether it reverses other costly-signaling predictions (e.g., Slantchev 2005) is not addressed. A qualitative conjecture in the blind rebuild and a rigorous derivation in the algebra check converge on the same sign. Empirical work on crisis-duration data with regime-type variation has a directional prediction to test, conditional on independent measurement of aia_i.

Formal replication is cheap and surfaces findings beyond what re-derivation alone produces. No closed-form equation in Reich's paper fails on independent derivation; the substantive cross-check confirms that, conditional on the war-of-attrition framing, the modeling choices are natural rather than discretionary; the joint exercise surfaces an unstated comparative static with conditional empirical bite.

Appendix A: Replication materials

  • Original paper. Reich, Noam (2024). "Dynamic Screening in International Crises." Journal of Politics 87(3). DOI 10.1086/732977. Verification target: December 13, 2023 R&R PDF, 75 pages, MD5 90bd652cdfee2832a0440872ae3b622b.
  • Verification artifacts. env/verification.md (aggregate report), env/algebra-check.md (line-by-line algebra), env/logic-check.md (proof-structure audit), env/notation-plausibility-check.md (notation/economic-plausibility audit), env/claim-index.yml (twelve-claim catalog with line-range pointers).
  • Substantive artifacts. env/topic-sketch.md (title-only sketch), env/blind-briefing.md (abstract-plus-intro briefing), blind-rebuild.md (zero-context rebuild), env/comparison-substantive.md (blind-rebuild–paper diff).
  • Craft notes. library/craft/paper-2026-0028--{puzzle-framing, analysis-strategy, theory-setup, validity-moves, narrative-arc}.md — five distilled lessons from the replication.
  • Full replication package (zip, 128 KB): https://www.dropbox.com/scl/fi/uevwv2b10x01zndjybufn/paper-2026-0028-replication-20260509-1313.zip?rlkey=osjnf9il3e44ld4x8tzat3oow&dl=1

References

Fearon, James D. 1994. "Domestic Political Audiences and the Escalation of International Disputes." American Political Science Review 88(3): 577–592.

Fearon, James D. 1995. "Rationalist Explanations for War." International Organization 49(3): 379–414.

Fearon, James D. 1997. "Signaling Foreign Policy Interests: Tying Hands versus Sinking Costs." Journal of Conflict Resolution 41(1): 68–90.

Hendricks, Ken, Andrew Weiss, and Charles Wilson. 1988. "The War of Attrition in Continuous Time with Complete Information." International Economic Review 29(4): 663–680.

Kurizaki, Shuhei. 2007. "Efficient Secrecy: Public versus Private Threats in Crisis Diplomacy." American Political Science Review 101(3): 543–558.

Levendusky, Matthew S., and Michael C. Horowitz. 2012. "When Backing Down Is the Right Decision: Partisanship, New Information, and Audience Costs." Journal of Politics 74(2): 323–338.

Nalebuff, Barry, and John Riley. 1985. "Asymmetric Equilibria in the War of Attrition." Journal of Theoretical Biology 113(3): 517–527.

Powell, Robert. 1988. "Nuclear Brinkmanship with Two-Sided Incomplete Information." American Political Science Review 82(1): 155–178.

Powell, Robert. 2017. "Taking Sides in Wars of Attrition." American Political Science Review 111(2): 219–236.

Reich, Noam. 2022. "Diplomatic Signaling under Audience Costs." Working paper.

Reich, Noam. 2023. "Audience Costs, Sunk Costs, and Resolve in Crisis Bargaining." Working paper.

Reich, Noam. 2024. "Dynamic Screening in International Crises." Journal of Politics 87(3). DOI 10.1086/732977.

Schelling, Thomas C. 1960. The Strategy of Conflict. Harvard University Press.

Schultz, Kenneth A. 1998. "Domestic Opposition and Signaling in International Crises." American Political Science Review 92(4): 829–844.

Schultz, Kenneth A. 2001. Democracy and Coercive Diplomacy. Cambridge University Press.

Slantchev, Branislav L. 2005. "Military Coercion in Interstate Crises." American Political Science Review 99(4): 533–547.

Snyder, Jack, and Erica D. Borghard. 2011. "The Cost of Empty Threats: A Penny, Not a Pound." American Political Science Review 105(3): 437–456.

Takahashi, Satoru. 2015. "Non-Equivalence between All-Pay and Winner-Pay Auctions under Incomplete Information." International Journal of Game Theory 44(4): 953–977.

Trachtenberg, Marc. 2012. "Audience Costs: An Historical Analysis." Security Studies 21(1): 3–42.

Trager, Robert F. 2010. "Diplomatic Calculus in Anarchy: How Communication Matters." American Political Science Review 104(2): 347–368.