SID: A Novel Class of Nonparametric Tests of Independence for Censored Outcomes
Pith reviewed 2026-05-23 07:45 UTC · model grok-4.3
The pith
Survival independence divergence equals zero if and only if a right-censored response is independent of its covariates.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The survival independence divergence metrics equal zero precisely when the right-censored response and the covariates are independent. They are obtained by applying a counting process strategy that recasts the original censored-data independence test as a test on complete observations, and they remain sensitive to various nonlinear dependence structures.
What carries the argument
The survival independence divergence (SID), constructed via a counting process strategy that converts the censored independence test into an equivalent complete-observation test.
If this is right
- The SID tests detect nonlinear dependence between the censored response and covariates.
- Empirical SID estimators possess established asymptotic properties under standard regularity conditions.
- Wild bootstrap procedures yield consistent critical values for the resulting tests.
- The tests achieve competitive power and size control relative to existing methods in simulation studies.
Where Pith is reading between the lines
- The counting-process reduction may allow similar independence tests to be developed for other censoring mechanisms by suitable adaptation of the process representation.
- Feature screening or variable selection procedures in censored regression could directly employ the SID as a dependence measure.
- The equivalence to complete-data testing suggests that many existing nonparametric independence tools become applicable once the counting-process transformation is applied.
Load-bearing premise
The counting process strategy equivalently transforms the intractable independence test due to the presence of censoring into a test problem for complete observations.
What would settle it
A collection of right-censored observations in which the response is independent of the covariates yet the estimated SID is statistically distinguishable from zero, or in which dependence is present yet the estimated SID remains zero.
read the original abstract
We propose a new class of metrics, called the survival independence divergence (SID), to test dependence between a right-censored outcome and covariates. A key technique for deriving the SIDs is to use a counting process strategy, which equivalently transforms the intractable independence test due to the presence of censoring into a test problem for complete observations. The SIDs are equal to zero if and only if the right-censored response and covariates are independent, and they are capable of detecting various types of nonlinear dependence. We propose empirical estimates of the SIDs and establish their asymptotic properties. We further develop a wild bootstrap method to estimate the critical values and show the consistency of the bootstrap tests. The numerical studies demonstrate that our SID-based tests are highly competitive with existing methods in a wide range of settings.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript introduces the survival independence divergence (SID), a new class of nonparametric metrics for testing independence between a right-censored response and covariates. A counting-process strategy is used to recast the censored-data problem as an equivalent complete-observation independence test; the resulting SID equals zero if and only if independence holds and can detect nonlinear dependence. Empirical estimators are defined, asymptotic properties and wild-bootstrap consistency are established, and simulation studies compare the tests favorably with existing methods.
Significance. If the counting-process equivalence and the accompanying consistency results hold, the work supplies a practical nonparametric tool for dependence testing in survival analysis, an area where right-censoring often precludes direct application of standard independence measures. The explicit zero-under-independence property together with the bootstrap procedure would be useful strengths for applied researchers.
minor comments (3)
- The abstract asserts that the counting-process transformation yields an “equivalent” complete-data problem, but the precise mapping (transformed variables, measure, and divergence) is not displayed; a short displayed equation or diagram in the introduction would improve readability.
- Notation for the censoring indicator and the at-risk process should be introduced once and used consistently; the current abstract mixes “right-censored response” and “counting process” language without a single reference definition.
- The numerical studies section would benefit from an explicit statement of the censoring rates and sample sizes used in each scenario, together with a table summarizing power at fixed nominal levels.
Simulated Author's Rebuttal
We thank the referee for the positive assessment of our manuscript and the recommendation for minor revision. The provided summary accurately captures the key elements of the SID framework, the counting-process equivalence, asymptotic results, and bootstrap procedure.
Circularity Check
No significant circularity detected
full rationale
The paper defines the SID metrics via a counting-process transformation that converts the censored independence test into an equivalent complete-data problem. The zero-iff-independence property is presented as a direct consequence of this construction rather than a fitted or self-referential result. Asymptotic consistency and bootstrap validity are established as separate analytic steps. No self-citation load-bearing steps, fitted-input predictions, or ansatz smuggling appear in the derivation chain. The central claim remains self-contained against external benchmarks.
Axiom & Free-Parameter Ledger
Lean theorems connected to this paper
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IndisputableMonolith/Cost/FunctionalEquation.leanwashburn_uniqueness_aczel unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
A key technique for deriving the SIDs is to use a counting process strategy, which equivalently transforms the intractable independence test due to the presence of censoring into a test problem for complete observations. The SIDs are equal to zero if and only if the right-censored response and covariates are independent
-
IndisputableMonolith/Foundation/RealityFromDistinction.leanreality_from_one_distinction unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
SID_β(T,X) = lim Δt→0+ ∫∫ ||φX|ΔNt,Yt(u,t) − φX|Yt(u,t)||² a(t) dw1(u) dν(t)
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
Reference graph
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