Practical aspects of compositional data analysis using regional geochemical survey data
Bibliographic record
Abstract
Government geological surveys and mineral exploration companies collect large amounts of geochemical\ndata, which are used in search for mineral commodities or for determining environmental\ndisturbances. These surveys consist of many thousands of samples (observations) with as many as\n50 elements determined for each. Because the nature of the data is compositional, they must be\ntreated according the protocols established by John Aitchison and others. This contribution details\nan approach based on the application of the alr, clr and ilr transforms for process discovery and validation.\nIssues of around the treatment of zeros and/or missing values are complicated due to the\nstoichiometric nature of the data. Case studies are presented where the use of logratio transforms\nand the estimation of replacement values for missing data are considered in the context of stoichiometric\nconstraints
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.055 | 0.210 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.005 | 0.007 |
| Science and technology studies | 0.002 | 0.003 |
| Scholarly communication | 0.007 | 0.005 |
| Open science | 0.004 | 0.004 |
| Research integrity | 0.002 | 0.003 |
| Insufficient payload (model declined to judge) | 0.005 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".