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Methodology

How every number is produced.

This page documents the instrument. It states what is measured, how it is measured, what is deliberately not measured, and where the method is weak. If a claim made elsewhere on this site is not supported here, this page is the one to believe.

RetrievalHighestCitationHighEvidence useModerateInterpretation fidelityModerateQuery breadthSupportingStabilitySupportingAvailabilitySupportingTVITVI_v0.1One number, never published without its parts.
The composite is assembled from 7 components. Bar length shows relative emphasis, not a published coefficient: Retrieval (highest), Citation (high), Evidence use (moderate), Interpretation fidelity (moderate), Query breadth (supporting), Stability (supporting), Availability (supporting).

Status of the index

The Trace Visibility Index is a product heuristic under active validation, not a validated scientific metric.

01

What Trace measures

One thing, in five parts: whether a specific publication participates in the answers generative systems give to a defined set of questions, and whether the finding survives that participation intact.

Retrieval

Share of questions where the paper enters the engine's retrieved source set.

Citation

Share of questions where the paper is visibly referenced in the answer.

Evidence use

Share where a claim in the answer is attributable to a finding in the paper.

Interpretation fidelity

Whether population, effect, and limitations survive the summary intact.

Query breadth

How many distinct question types reach the paper at least once.

Stability

Consistency of the result across repeated runs, engines, and model versions.

Availability

Whether the identifier resolves and the full text is reachable by a crawler.

Each is observed independently and reported independently. Demo-workspace figures used across this site — 62% retrieved, 43% cited, 31% evidence used, 27% interpreted faithfully — come from the same run against the same question set.

02

What Trace does not measure

This list is longer than the previous one, and that is the honest shape of the problem. Reading a visibility number as a quality signal is the single most damaging mistake a reader of this product can make.

Research quality

Nothing here evaluates study design, statistical validity, or whether a result is true. A well-designed study can score poorly, and a weak one can score well.

Clinical validity or safety

No output is a clinical assessment, and none of it should inform patient care. Visibility is not evidence of efficacy.

Whether a paper deserves to be cited

Merit is a judgement for peer review and the scientific community. This measures what engines do, not what they ought to do.

Scientific importance or novelty

A foundational method paper and a minor replication are measured by the same instrument, which is aware of neither.

Human readership

Downloads, reads, and altmetrics are outside scope. Retrieval by a machine is not evidence that a person read anything.

Causation

Changes are recorded with dates and adjacent events. No claim is made that any change was caused by any action, including actions taken in this product.

Stated plainly

The composite score is a product heuristic. It has not been validated against any external measure of research quality, influence, or outcome, and it should not be used in hiring, promotion, funding, or evaluation decisions about people.

03

Query generation

A visibility number without a denominator is meaningless, so the question set is the first artefact produced and the first one you can edit.

Candidate questions are derived from the paper’s own structured content: population, intervention or exposure, comparator, outcomes, setting, and stated limitations. Each candidate is assigned a question class — clinical decision, mechanism, comparative, safety, population, or evidence strength — and a difficulty level reflecting how specific an answer must be.

Candidates are then filtered for answerability. A question the paper genuinely cannot inform is excluded, because including it would depress every score for a reason that has nothing to do with visibility.

The resulting set is presented for review before any run. You can remove questions, add questions, and change class assignments. The final set is frozen, versioned, and stored with every run made against it. Changing the set starts a new series rather than continuing the old one.

04

Sampling

Engines are non-deterministic. A single query returns an anecdote, not a measurement.

Every question is issued multiple times per engine within a run, with a fixed interval between repeats and no carried-over conversation state. Repeats are independent sessions; a follow-up in the same thread would measure the thread, not the index.

Results are aggregated per question before being aggregated per paper, so a question that happens to be asked more often does not dominate. Sample size, run window, and the number of repeats are recorded with the run and shown in every report.

Where a question returns a refusal or an error, the outcome is recorded as such rather than as an absence of the paper. Silently coding failures as negatives would bias every component downward.

05

Engine definitions

An engine is a named surface with a named configuration, recorded at the time of the run.

Recorded per engine

What defines a measurable surface

  • Surface class: general assistant, search-grounded answer engine, research assistant, or retrieval API
  • Model and version identifier where the provider exposes one, and the observation date where it does not
  • Whether live web retrieval was enabled for the run
  • Region and language of the request
  • Whether the surface exposes its retrieved sources, or whether retrieval must be inferred

Results are reported per engine and never averaged into a single cross-engine figure without the per-engine detail beside it. Engines differ enough that the average is often true of none of them.

06

Retrieval detection

Retrieval means the paper entered the source set the engine considered, whether or not the reader ever saw it.

Where a surface exposes its retrieved sources, detection is direct: identifiers are matched against the paper’s DOI, its preprint and accepted-manuscript versions, and known aliases. Version linkage matters, because retrieval of a preprint is retrieval of the work.

Where sources are not exposed, retrieval is inferred from observable evidence in the answer, and the record is explicitly marked as inferred. Inferred retrieval is reported separately from observed retrieval and is never presented as equivalent.

Known error modes: an engine may name a source it did not retrieve, and may retrieve a source it never names. Both are counted against confidence in the estimate rather than corrected silently.

07

Citation detection

Citation means a reader of the answer could identify the paper as a source.

Detection matches identifiers first — DOI, PubMed identifier, arXiv identifier — then resolvable links, then title and author strings normalised for punctuation, diacritics, and abbreviated journal names. A match on title alone is recorded at lower confidence than a match on an identifier.

Fabricated references are a real failure mode of generative systems. A reference that names the paper but resolves to nothing, or resolves elsewhere, is recorded as a malformed citation and reported in its own category rather than being counted as a citation.

08

Evidence-use detection

Evidence use asks a different question from citation: did a claim in the answer actually come from this paper?

Claims in the answer are segmented and each is checked against the paper’s reported findings — effect sizes, endpoints, populations, and stated conclusions. A claim counts as evidence use when it is specific enough to be attributable and consistent with what the paper reports.

This produces two informative asymmetries. A paper can be cited without its evidence being used, where the reference is decorative. A paper’s evidence can be used without being cited, where the finding has become background knowledge and attribution has been lost. Both are reported, because they call for different responses.

Detection is model-assisted and audited against human coding on a sampled subset. The measured agreement rate is published with each methodology version rather than described qualitatively.

09

Interpretation fidelity

Being found is not the same as being understood. Fidelity checks whether the finding arrives intact.

Checked per answer

Distortions that are detected

  • Population generalisation: the result is stated for a broader group than was studied
  • Effect inflation: magnitude, certainty, or direction is overstated relative to what was reported
  • Causal upgrade: an association is described as a cause
  • Limitation loss: a stated limitation or exclusion disappears from the summary
  • Endpoint substitution: a secondary or surrogate outcome is presented as the primary result
  • Context loss: comparator, dose, duration, or setting is dropped

An answer is scored as faithful only when no distortion is detected. Fidelity is therefore a strict measure, and a low fidelity share is common even for clearly written papers.

10

Stability

A result that changes every time it is measured is not a result. Stability is reported as a component, not buried as an error bar.

Three kinds of variance are tracked: within-run variance across repeats of the same question, across-engine variance for the same question, and across-run variance over time. Each is reported separately, because they have different causes and different remedies.

Measured variance also sets alerting thresholds. A change is only surfaced when it exceeds the noise the instrument is known to produce, which is why alert volumes are low by design.

11

Trace Visibility Index

One number, published only alongside the components that produced it. Each component is weighted; the ordering below is the judgement the index encodes.

TVI · TVI_v0.1

weights sum to 1.00

Retrievalrelative emphasis Highest
Share of questions where the paper enters the engine's retrieved source set.
Citationrelative emphasis High
Share of questions where the paper is visibly referenced in the answer.
Evidence userelative emphasis Moderate
Share where a claim in the answer is attributable to a finding in the paper.
Interpretation fidelityrelative emphasis Moderate
Whether population, effect, and limitations survive the summary intact.
Query breadthrelative emphasis Supporting
How many distinct question types reach the paper at least once.
Stabilityrelative emphasis Supporting
Consistency of the result across repeated runs, engines, and model versions.
Availabilityrelative emphasis Supporting
Whether the identifier resolves and the full text is reachable by a crawler.

The weights encode a judgement: that being retrieved matters more than being visibly cited, and that fidelity is worth as much as evidence use. That judgement is arguable. It is stated here so it can be argued with, and it is versioned so a change to it is visible.

The exact coefficients are not on this page by design. They belong where they can be checked against a number: the app prints each weight beside its component, and every export pins the full weighting to a methodology version. A marketing page cannot be held to that. A versioned artefact attached to your own score can.

The Trace Visibility Index is a product heuristic under active validation, not a validated scientific metric.

12

Field normalization

Retrieval rates differ enormously between fields for reasons that have nothing to do with any individual paper.

A well-indexed clinical topic with open full text behaves differently from a specialised topic with few open sources. Raw component values are therefore reported alongside a field-relative view, computed against papers sharing subject area, publication year window, and access status.

Field-relative values are only shown where the comparison group is large enough to be meaningful; below that threshold the raw values are shown alone and the reason is stated. Comparisons are never drawn across unlike fields, and no cross-field ranking is produced.

13

Simulation methodology

Synthetic panels are language models responding in declared roles. They are not survey participants, and nothing they produce is human data.

Each synthetic respondent is defined by an explicit, stored profile: role, discipline, seniority, evidence threshold, and prior exposure. Respondents answer independently first, then optionally see each other’s reasoning and revise. Both rounds are retained along with the reason given for each revision.

Runs are repeated to measure how stable a panel’s conclusions are under identical inputs, and role wording is perturbed to test how sensitive results are to prompt phrasing. Both figures ship with the output.

Modelled stakeholder response, calibrated against real published clinical discourse. Directional research intelligence — it complements human validation rather than replacing it.

Simulation in detail

14

Validation

Validation is in progress. This section describes what has been checked and what has not, and it will grow more specific with each methodology version.

Checks currently run

  • Agreement between automated detection and human coding on a sampled subset of answers
  • Repeatability of each component across independent runs of the same question set
  • Sensitivity of results to question phrasing within the same question class
  • Detection of deliberately introduced distortions in a held-out set of summaries

Not yet established

  • That the composite predicts any downstream outcome, including citation, adoption, or use
  • That component weights are optimal, or better than an unweighted alternative
  • That results generalise beyond biomedicine and English-language sources
  • That inferred retrieval approximates observed retrieval closely enough to be pooled

Negative results are published alongside positive ones. A methodology page that only reports what worked is an advertisement.

15

Limitations

Known and unresolved. Each of these affects how much weight any number on this site can carry.

Generative engines are non-deterministic and change without notice; any measurement is a sample of a moving system.

Retrieval is partly inferred from observable outputs, because most engines do not publish their retrieved source set.

Question sets are constructed, so they approximate rather than reproduce what people actually ask.

Coverage is uneven across languages, fields, and regions, and is weakest outside biomedicine and English.

Detection of evidence use and fidelity relies on model-assisted judgement, which has its own error rate — reported, not hidden.

The composite is a product heuristic. Its weights encode a point of view about what matters and have not been validated against any external outcome.

16

Version history

Every score is stamped with the methodology version that produced it. Historical scores are never recomputed under a new version without being relabelled.

Changelog

Methodology versions

Methodology versions with release date and summary of changes.
VersionDateChange
TVI_v0.12026-08-15Initial public methodology