Testing distributional symmetry about an unknown center is a composite-null problem in which signed information contrasts can cancel under asymmetric alternatives. We developed a two-layer framework built on reflected probability kernels from paired consecutive reliability systems: Global fractional-entropy identities characterize symmetry, while a positive-weight complementary log-quantile-density discrepancy measures local departures without cancellation. The discrepancy identified symmetry for any strictly positive weight; the consecutive-system kernels supplied a structured, reliability-interpretable choice rather than a necessary or optimal one. We proved consistency of the moving-spacing estimator under explicit conditions and gave a compact-support sufficient class with uniform control of all complete windows, including boundary windows. For finite-sample inference, we introduced ACES-R, a distinct blockwise reflection-randomization core with finite-sample level control over the composite symmetry null, without estimating the center. Sign-paired ties generally made its complete-orbit levels conservative, and fixed-block consistency held on the stated compact-support class. A separate Monte Carlo member used a prespecified quadratic statistic. Blocking carried an information cost: ACES-R exhibited lower raw rejection rates than full-sample ACES in the reported asymmetric settings, and its finite-group guarantee did not validate the full-sample bootstrap calibration. Full-sample ACES combined the score orders 1, 3/2, and 2 in a symmetrized-bootstrap standardized maximum whose primitive bootstrap validity and joint null limit remained unproved. Paired-sample simulations quantified the blocking-power trade-off and examined Student-t, Cauchy, and skew-t settings without claiming equal-size or uniform power superiority; classical and characteristic-function benchmarks, ablations, rounding diagnostics, and two engineering datasets mapped empirical strengths and limitations, with any heavy-tail power advantage remaining exploratory. Archived code, seeds, and replicate-level outputs support reproducibility of the paired-sample experiments.
Citation: Ibrahim A. Nafisah, Tahani Alshathri, Mashael A. Alshehri. Cancellation-free distributional symmetry testing via reliability-inspired consecutive-system entropy scores[J]. AIMS Mathematics, 2026, 11(11): 36293-36355. doi: 10.3934/math.20261406
Testing distributional symmetry about an unknown center is a composite-null problem in which signed information contrasts can cancel under asymmetric alternatives. We developed a two-layer framework built on reflected probability kernels from paired consecutive reliability systems: Global fractional-entropy identities characterize symmetry, while a positive-weight complementary log-quantile-density discrepancy measures local departures without cancellation. The discrepancy identified symmetry for any strictly positive weight; the consecutive-system kernels supplied a structured, reliability-interpretable choice rather than a necessary or optimal one. We proved consistency of the moving-spacing estimator under explicit conditions and gave a compact-support sufficient class with uniform control of all complete windows, including boundary windows. For finite-sample inference, we introduced ACES-R, a distinct blockwise reflection-randomization core with finite-sample level control over the composite symmetry null, without estimating the center. Sign-paired ties generally made its complete-orbit levels conservative, and fixed-block consistency held on the stated compact-support class. A separate Monte Carlo member used a prespecified quadratic statistic. Blocking carried an information cost: ACES-R exhibited lower raw rejection rates than full-sample ACES in the reported asymmetric settings, and its finite-group guarantee did not validate the full-sample bootstrap calibration. Full-sample ACES combined the score orders 1, 3/2, and 2 in a symmetrized-bootstrap standardized maximum whose primitive bootstrap validity and joint null limit remained unproved. Paired-sample simulations quantified the blocking-power trade-off and examined Student-t, Cauchy, and skew-t settings without claiming equal-size or uniform power superiority; classical and characteristic-function benchmarks, ablations, rounding diagnostics, and two engineering datasets mapped empirical strengths and limitations, with any heavy-tail power advantage remaining exploratory. Archived code, seeds, and replicate-level outputs support reproducibility of the paired-sample experiments.
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Paired consecutive 2-out-of-3 system densities and complementary entropy-score imbalance for normal and lognormal distributions. The local imbalance is zero under normal symmetry
Repair-time histogram with kernel density estimate, normal Q–Q plot, and signed local score $ \mathit{\boldsymbol{C}}\left(\mathit{\boldsymbol{u}}\right)-\mathit{\boldsymbol{C}}({\bf{1}}-\mathit{\boldsymbol{u}}) = \mathit{\boldsymbol{l}}\mathit{\boldsymbol{o}}\mathit{\boldsymbol{g}}\mathit{\boldsymbol{q}}\left(\mathit{\boldsymbol{u}}\right)-\mathit{\boldsymbol{l}}\mathit{\boldsymbol{o}}\mathit{\boldsymbol{g}}\mathit{\boldsymbol{q}}({\bf{1}}-\mathit{\boldsymbol{u}}) $. The dashed curve shows the normalized discrete grid weights $ {\mathit{\boldsymbol{W}}}_{\mathit{\boldsymbol{i}}} $, not the continuously normalized weight function
Histogram with kernel density estimate and normal Q–Q plot for the tensile-strength observations
Signed complementary log-quantile-density difference for the tensile strengths and normalized discrete weights. This is a descriptive curve, not a simultaneous confidence band or an independent test at each probability level