CosmoStat / CosmoStat/shapepipe

Weighted vs unweighted m-bias disagree in the latest image-sim runs

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#885 4 comments 0 reactions 2 assignees View on GitHub

@martinkilbinger is already working on this.

Since Sep 8, 2026.

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Description

Recent runs with the WCS fix give m consistent with zero, but weighted and unweighted estimates differ — unexpected given earlier tests where weights did not move the m-bias (see Fabian's comment in UNIONS-WL/MultiBand_ImSim#1: https://github.com/UNIONS-WL/MultiBand_ImSim/issues/1#issuecomment-5066465616). Understand the difference before the m-bias is called done. Related: uberseg (#776) is implemented but reportedly not enabled and made no difference on blended sims.

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