DES Y6 Lens Bin 2 Anomaly Investigation

Systematic hypothesis testing for the MagLim++ bin 2 PPD failure

Cross-Bin PPD Results

Binz rangeχ2νp-valueStatus
0[0.20, 0.40]1.010.594PASS
1[0.40, 0.55]1.180.384PASS
2[0.55, 0.70]1.780.022ANOMALOUS
3[0.70, 0.85]0.870.758PASS
4[0.85, 0.95]0.650.932PASS
5[0.95, 1.05]0.880.752PASS

Hypothesis Assessment

HypothesisScannedFailuresViable?
Photo-z Bias210No
Magnification150No
Galaxy Bias160No
Covariance161YES

Most Likely Cause

Covariance Misestimation

The anomaly is isolated to bin 2. Only covariance modeling produces PPD failures.

Cross-Bin Chi-Squared

Mode Coefficient Tension

Hypothesis Scan: Photo-z Bias Effect on p-value