The French-Wilson prior of each reflection is now epsilon * K_shell * a(h), with
a(h) = exp(-1/2 s^T B s) from the deviatoric tensor AnalyzeAnisotropy already fits
(the form it is fitted in) and K_shell = sum(I/eps) / sum(a), so a shell's priors still
average to its measured mean. The amplitudes are made isotropically at the merge as
before and made again once the tensor exists (full pipeline and --mode scale). Only
F/SIGF and F(+)/F(-) change; IMEAN/I(+)/I(-) are bit-identical. Applied whenever a
tensor was fitted, with no detection gate: a near-isotropic tensor gives a(h) ~ 1 and
the isotropic prior back, and the prior wants the best estimate of <I> along h whatever
its cause. Follows ctruncate's anisotropic prior (Ballard & Stein, CCP4); credit in
ACKNOWLEDGEMENT.md, CPU_DATA_ANALYSIS.md and at the algorithm.
--model scaling (ModelScaling.cpp) was checked: k_overall + symmetry-constrained
anisotropic B + flat bulk solvent fitted on the working set, against the same FW F
written to the MTZ - as REFMAC/phenix.refine do. No change needed.
Evidence (REFMAC 10-cycle restrained refinement of the deposited model, R-free on
the depositor's free reflections shared by both data sets; base = rc174 processing,
same IMEAN):
set base new d set base new d
9rcs 0.3475 0.3494 +0.0019 8qq7 0.4452 0.4503 +0.0051
9yzk 0.3192 0.3171 -0.0021 9hs7 0.2898 0.2465 -0.0433
6yqf 0.4642 0.4543 -0.0099 5nw5 0.3256 0.3206 -0.0050
7n2s 0.3126 0.2998 -0.0128 6z8o 0.2927 0.2892 -0.0035
6qaj 0.3390 0.3038 -0.0352 6moj 0.2756 0.2651 -0.0105
6r72 0.3826 0.3797 -0.0029 7qij 0.3239 0.3140 -0.0099
anisotropic sets: median -0.0075, mean -0.0107, 10/12 better
isotropic controls: 5reo -0.0014, 7kcn +0.0003, 6fid +0.0002, 11if 0.0000
rugnux's own --model R-free moves the same way (median about -0.019; 5nw5 +0.006),
R_model shell-scaled too; dep_cc_delta unchanged (intensity based). The adoption rule
(median gain >= 0.005 on the anisotropic sets, no control worse than +0.002) is met.
The two sets that lose are the one with a FLAT resolution signature (8qq7) and 9rcs,
where the exp form drives the dead direction's prior to ~0 beyond 3.7 A.
For scale: ctruncate's own anisotropic prior on the same merges moved the same
REFMAC R-free by a median of only -0.0008 (9hs7 +0.026).
Inhouse lyso_x06da_ref, thau_x10sa_0p1deg: every battery metric unchanged.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K5K8jvPPbmCrbqnWkddTuB
leonarski_fandClaude Opus 5.5
4979f8aa68
