Frozen retrospective missing-view ranking comparison

Frozen retrospective missing-view ranking comparison

12 October 2026. Distinct unit within the accepted seven-day multi-survey program, following verified eligibility and association audits. This does not restart E13/CLIP, E22/E28 or the stopped occurrence comparison. Historical chemistry outcomes and covariate findings are already consumed; registering a new method does not turn them into fresh physical validation.

Falsifiable question and outcome

Does a label-free six-dimensional shared representation improve recovery of a withheld consumed chemistry proxy over both linear and nonlinear tabular baselines at identical spatial review budgets? Learn from infrared, variability and non-withheld dense-gas measurements with explicit missing views. Assess in held-out sky tiles. Retain every 19,328 requested clump and unknown proxy.

Primary endpoint: minimum of two paired differences in qualifying-positive recovery (embedding minus linear baseline; embedding minus nonlinear baseline), at the fixed tile-wise review rule below. Retrospective support requires this minimum >=0.10 and its 95% paired spatial-bootstrap lower endpoint >0. Adequacy requires >=15 qualifying positives, >=80 qualifying proxy negatives and >=4 populated 10-degree tiles, finite common-support predictions, and no invalid populated fold. If adequate but the benefit gate is not met, conclude no retrospective gain demonstrated; this is not equivalence or a physical null. If adequacy/fitting/source checks fail, conclude insufficient evidence and retain all incomplete outputs. A supported retrospective gain is not independent physical classification, population precision/recall or a newborn-star result.

The historical 303-object chemistry check had 26 positives, so only very large improvements could be discerned. The minimum-count gates prevent a trivial few-object success; they are not a conventional power guarantee. The bootstrap will expose attainable precision. No sample-size, endpoint, threshold, model or feature changes after new readout. Do not tune on test labels.

Exact population, features and censoring

Use the verified 19,328-clump nearby Hi-GAL parent; sorted designation strings and source hashes are frozen in registration. All reliable catalogue objects remain neighbour context in the prior edge ledger. One-record/unshared molecular support at 30 arcsec is required for gas features and proxy adjudication. The 32 ambiguous/shared cases retain their edges and unknown proxy state; no row is dropped from the all-requested output. All four input/output tracers come from the same instrument and environment: withholding the latter prevents direct feature leakage but does not establish conditional independence.

The four evaluation-only fields are DHC3N, DHNCO404, DCH3CN and DSIO. At an unambiguous native record, any ‘Y’ is a qualifying proxy positive; four ‘N’ values are a qualifying proxy negative. Marginal ‘M’, missing/other flags with no ‘Y’, absent records and ambiguous ownership are unknown, not negative. These are chemistry labels, not physical absence/presence of a protostar. All raw flags were historically consumed; every label has that role. No old model scores, stage probe, 70-micron flux, Lbol, Tbol or evolutionary label is an input.

The feature order below is fixed; values are float64, missing entries NaN with separate Boolean masks. Observed/censored/quality-missing states remain in the source-bound inputs and ledgers. Missing values are never interpreted as zero flux or absent stars. Model standardisation/imputation is distinct from those scientific states.

0–4: log10 mass, temperature, log10 distance, log10 surface density, log10 diameter. Positive finite values required; temperature is unlogged. These five physical covariates are also supplied directly to the embedding ranker and both baselines. Surface density is only a column proxy, not a validated line-of-sight extinction control; the failed 333/800 column uncertainty gate is unchanged.

5–11: ln F160, ln F250, ln scaled-F350, ln scaled-F500, and consecutive log flux ratios. F160/F250 require positive finite corresponding quoted errors as well as positive flux; scaled350/500 require positive finite values, with absent quoted errors explicitly unverified. The scaled fields are fsc350/fsc500, not their uncertainties. No pixels, native photometry reconstruction or upper-limit fit.

12–15: W1−W2, W2−W3, W3−W4 and W2 magnitude from the retained AllWISE anchor within 3 arcsec. Each contributing band requires finite magnitude, SNR>=5, its cc_flags character ‘0’, and ext_flg=0. Errors/alternatives/native IDs missing in this derived table remain unverified. Low-SNR upper-limit-like values are not substituted as detections. These catalogue values are provisional input context.

16–19: mean supported-visit W2 magnitude, ln(1+reduced constant-fit chi-square), visit-mean peak-to-peak range and weighted slope in mag/year. Use only the previously frozen anchored temporal-support subset: same available-field screen, 2-arcsec anchor radius, exact five-string deduplication, >30-day gaps, >=5 tuples per supported visit, >=3 supported visits and >=365-day overall anchored span. For a supported visit compute inverse-quoted-variance weighted mean magnitude; variance is 1/sum weights plus a fixed 0.03^2 mag^2 analysis floor. That floor is an assumption, not measured calibration. Use supported visits only for features. No p-value, physical event or uncertainty coverage is inferred from the quoted error model. Preserve unscreened and unanchored alternatives in original bytes.

20–27: for each of HCOP, HNC, N2HP, HCN, asinh(II/e_II) and ln FWHM. Require positive finite e_II and finite II for the former, positive finite FWHM for the latter, and NG in {1,2,3}. NG is the fit form/validity flag, not a count of stars. No detection flags for these input lines are used. The four withheld tracers’ measurements/NG/noise/derived flags and the catalogue IR-based S category are excluded from inputs. Keep all native molecular IDs and geometric alternatives.

Infrared/context columns 0–15 form one view, temporal 16–19 a second, and molecular 20–27 a third. Fixed per-column loss scales are 1/sqrt(view dimension). This scales dimensions, not a proven observation-noise likelihood. The model does not assume missingness is random; explicit feature-availability masks enter all rankers and missing-view strata are reported.

Frozen spatial splits and fitting

Use 10-degree Galactic-longitude tiles, floor(glon/10), with longitude in [0,360). The nominal fold is tile modulo five. Parent clumps sharing a molecular-position component are assigned the fold of that component’s lexicographically smallest source; identical retained AllWISE coordinate pairs are additionally joined. Store the group and tile for every ID. Entire groups stay out of training when held out. A one-degree circular-longitude buffer around every nominal held-out 10-degree interval excludes nearby training rows, even if a component assignment moves a case across a tile boundary. This guards nearby duplicate WISE queries without asserting reconstructed native identity. Actual split arrays and hashes must be inspected in the pre-read registration. Labels do not determine splits.

For each of five folds, train feature scaling and the embedding only on other folds outside the buffer. All unlabelled parent training rows are allowed; never use held-out rows to fit scaling, missing-value completion or a basis. Use only qualifying proxy labels in training groups to fit downstream rankers. At least five training positives and twenty training negatives are needed; a fold failing this is recorded invalid, not re-partitioned. A fold with no qualifying test labels still gets all-requested predictions if training is eligible.

Standardise each feature by training observed median and IQR; if no observations, use median=0 and scale=1. If IQR<1e-8 use scale=1. Clip standardised values to [-5,5]; set missing entries to zero for tabular baselines, alongside masks. No test-specific feature scaling.

Shared representation: fixed rank six iterative low-rank completion. Initialise missing scaled entries at zero, run exactly twenty full-SVD iterations, retaining rank-six reconstruction only at missing entries and clipping those to the same view-scaled range. Reinsert every observed entry unchanged at each iteration. Centre the completed matrix each iteration; final centred SVD defines the basis. This is an explicit low-rank completion procedure, not a calibrated probabilistic PCA likelihood, a deep neural network or a claimed new method. Encode each row from only its observed columns by ridge least squares (ridge=0.01) against that basis and centring vector. Six coordinates are fold-specific; do not pool them into an allegedly global latent map or fit test data to align them.

Three primary rankers:

One fixed infrared-only ablation uses the same rank-six/20-iteration procedure on columns 0–15, with its latent coordinates, physical controls and 16 masks in an otherwise identical kernel ranker. It is diagnostic, not a selectable primary. No model/hyperparameter sweep, learning on proxy test labels or old CLIP execution. All scores are ranking scores, not calibrated physical class probabilities.

Review budgets, uncertainty and confounding

Within each held-out 10-degree tile, select ceil(0.05*N) objects with the highest score, ties broken by exact designation, separately for each method. For the primary common qualifying-proxy cohort, N counts only qualifying positive or negative proxies with valid predictions for every primary method. Require all qualifying proxies to have valid common predictions for an adequate readout; otherwise report incomplete support instead of silently reducing that cohort. Keep unknowns in the all-requested ledger and denominator. Report the actual rounded review counts/fractions; small tiles need not realise exactly 5%.

Separately apply the same rule to every requested source in each tile and record selected proxy positives, proxy negatives and unknowns for each method. This all-requested diagnostic is not population precision/recall: its truth is selected and incomplete. Never exclude unknown selections from a claimed physical precision denominator. No pooling or calibration of fold-specific latent spaces; review comparisons use within-tile ordering, not cross-fold raw score cutoffs.

Use 2,000 paired bootstrap draws of populated qualifying-proxy tiles, sampling whole tiles with replacement, seed 20261012. Recompute recovery differences from fixed held-out selections and apply min(delta_linear,delta_nonlinear) per draw. Discard draws with no proxy positives, report the discarded count; require at least 1,900 retained draws. Percentile endpoints at 2.5/97.5%. All methods have the same tile-wise reviews in every draw. This conditional spatial interval is not an uncertainty bound on a hidden-protostar fraction or a survey detector.

Report recovery/selection by missing temporal/gas support, and low/high mass, temperature, distance and surface-density strata using the global input-only parent medians (outcomes do not set those divisions). Include the infrared-only ablation, and descriptive covariate means/ranges of qualifying versus unknown cohorts. These expose selection/confounding; they do not repair the stopped column-matched occurrence estimator or establish causal effects.

Reproduction, evidence and stopping

Freeze exact input/code/protocol hashes, feature names, seeds and all-source split CSV before any new line/magnitude/variance readout. Geometry/missingness from the verified association ledger may set these splits without labels. Persist feature values/masks, all source and native-record joins, unknown proxy states, five fold models, unaligned fold coordinates, all-requested out-of-fold scores/review flags, proxy comparisons, bootstrap and caveats. Independently reconstruct features/labels/splits from raw bytes and recompute the paired readout. Verify solver stationarity, conditional encoders and saved kernel coefficients numerically without importing the generator. Synthetic tests cover missingness, forbidden-label invariance, exact ties, wrap-around buffers and known linear-system solutions before real readout. Independent software replay is not fresh physical validation.

Worker and checker each <=1,800 seconds, one CPU, <=256 MiB sampled RSS. Combined outputs <=16 MiB, below the research 64 MiB ceiling, with a fresh guarded worker stage cap 12 MiB and checker cap 4 MiB, and final combined check. Keep 5 GiB free. No network observations, downloads, GPU, cloud jobs, native-input deletion, private Atlas/E155/E121 actions or archived experiment execution. Preserve failed attempts and stop after the frozen question. Model success cannot authorize an automatic successor, scientific threshold adjustment or physical discovery.

A verified retrospective positive/null/insufficient result advances the accepted comparison but cannot complete independent detector requirements. Any physical candidate cards (at most twenty) require separately bound evidence and explicit known/provisional/unknown status. No publication or cloud-app inference is claimed merely by local execution; follow the existing blog publication checks for a meaningful verified result.

Primary sources: MALT90 catalogue, section 4, official NEOWISE column definitions. Roweis 1997 provides historical context for missing-data subspaces; the exact completion procedure above is defined by this registration and is not asserted to be that paper’s probabilistic algorithm. Native fit/photometry uncertainties are not replaced by an assumed latent-space likelihood.