Classification & Taxonomy

← Back to Mechanisms by Solution Family

Solutions that sort cases into meaningful classes, establish membership criteria, or organize concepts so distinctions can guide action.

42 mechanisms across 5 solution archetypes in this solution family. A mechanism inherits the primary family of the archetype it instantiates; family is about the move the solution makes, not the domain where it originated.

Canonical Classification

Create stable membership classes so entities can be compared, governed, routed, interpreted, or processed consistently.

4 mechanisms · View full solution archetype

• Diagnostic Category System — Sorts observed cases into named condition or fault types to steer interpretation, tagging each assignment with an explicit confidence and keeping ambiguous cases provisionally open for reclassification.
• Eligibility Class System — Sorts applicants into qualification classes by testing evidence against stated criteria, with a contestable appeal path and explicit rules for what happens when a case's facts or the criteria themselves change.
• Filing Code System — Assigns each record a stable code drawn from a governed code map and held in one authoritative register, so items can be filed, found, and reported consistently across offices and years.
• Severity or Triage Scale — Ranks cases into ordered urgency or severity levels so that everything in a level gets the same response intensity, with the level thresholds audited against how cases actually turn out.

Cascaded Hierarchical Recognition

Recognize complex cases by moving attention through a hierarchy of coarse filters and fine discriminators instead of trying to inspect every possible feature at once.

9 mechanisms · View full solution archetype

• Cascade Error Audit — Analyzes false positives, false negatives, delays, and reviewer disagreement by stage.
• Coarse Screening Checklist — Gives human reviewers a short high-recall set of initial cues before deeper review.
• Drilldown Recognition Interface — Allows users to move from broad category cues to progressively finer evidence while preserving the candidate set.
• Expert Review Checkpoint — Places human or specialized review at stages where automated or novice recognition is unreliable.
• Feature Pyramid or Hierarchical Model — Represents input at multiple levels of resolution so broad structure and fine detail can be processed in order.
• Multi-Stage Classifier Pipeline — Implements sequential classifiers where earlier stages screen broadly and later stages classify surviving candidates in finer detail.
• Salience Map or Attention Heatmap — Shows where attention should move next based on current stage evidence.
• Stage Transition Log — Records candidate survival, rejection, branching, confidence changes, and rationale at each stage.
• Triage Queue with Escalation Rules — Routes cases from initial screen to routine handling, specialist review, manual inspection, or emergency response.

Category Boundary Audit

Audit the boundary of a category to reveal hidden assumptions, exclusions, edge cases, and consequences before the category is trusted for action.

8 mechanisms · View full solution archetype

• Appeals Case Review — A workflow for reconsidering an individual contested classification when the default criteria fail to represent the case, and for feeding recurring appeals back into the boundary.
• Boundary Critique Review — Interrogates a category boundary with structured critical questions about who is inside, outside, privileged, silenced, and externalized — surfacing the power and assumptions the line quietly encodes.
• Category Governance Record — A living record of a category's criteria, rationale, decision authority, and revision history, so its boundary can be maintained accountably instead of drifting in silence.
• Classification Fairness Review — Measures how a classification's errors — false inclusions and false exclusions — distribute across affected groups, exposing the burden and invisibility a formally neutral boundary can still produce.
• Edge-Case Analysis — Works a corpus of hard, borderline, and novel cases to expose where a category boundary is arbitrary, underspecified, or out of step with what the category is for.
• Eligibility Audit — Runs a program's eligibility criteria against a panel of real and hypothetical applicants to check that they admit the intended cases, exclude only what the purpose requires, and treat borderline claims consistently.
• Ontology Audit — Checks whether a category and its boundary still cohere with the wider domain model of entities, relations, and contexts it is supposed to live inside.
• Taxonomy Review — Inspects the structure of a classification scheme — its levels, labels, sibling splits, and groupings — for the cross-cutting cases and unstable seams that a clean hierarchy quietly hides.

Inclusive Membership Union Design

Pool collections by inclusive membership without losing identity, provenance, or overlap visibility.

9 mechanisms · View full solution archetype

• Canonical Identity Resolution Pass — Turns each source collection's own identifiers into one canonical member key, so the same real-world entity is recognized as the same member wherever it appears.
• Deduplicating Union Pass — Materializes the union set by emitting each canonical member exactly once, collapsing repeated appearances and folding their provenance into a single record.
• Inclusive-OR Membership Test — A per-element predicate that answers 'is this a member?' with yes the moment the element appears in at least one admissible source, without building the whole set.
• Overlap and Coverage Dashboard — Renders the union's overlap structure and per-source coverage at a glance, and stamps the standing warning that any-source membership is not validation.
• Provenance Tagging Protocol — Attaches to each union member a durable record of which sources supplied it — with version, timestamp, and membership criterion — keyed to its canonical identity.
• Source Collection Ingestion Workflow — Registers each contributing collection as a first-class source and defines how an absent, empty, or failed source is handled — so the union knows exactly what it is unioning.
• Type Compatibility Checklist — A pre-union gate that checks each candidate source's elements are the same kind of thing, in the same universe, before it is allowed to contribute members.
• Union Delta Review — A version-over-version review of the union that separates genuine membership change from source outages, using provenance timestamps to explain every add and drop.
• Union Specification Sheet — A single declared document that fixes the union's universe, its contributing sources, and the downstream-use label — the contract every other mechanism is built against.

Prototype-Centered Category Modeling

Model a category by its clearest examples and graded resemblance to them, rather than pretending every useful category has a crisp essence.

12 mechanisms · View full solution archetype

• Boundary Case Review Panel — A standing panel that adjudicates the hard cases no rule resolves, turning each decision into boundary precedent and serving as the category's appeal path.
• Calibration Workshop — Convenes the people who judge the category to align on shared reference cases and on how context reweights typicality, so their independent calls converge.
• Card Sort or Example Sort — Has people sort real examples into piles so the category's natural dimensions, sub-groups, and fuzzy edges surface from behaviour rather than from a definition.
• Classification Disagreement Audit — Measures where classifications diverge — reviewer vs reviewer, human vs model — to expose systematic bias and human-model misalignment.
• Drift Sample Review — Periodically re-judges a fresh sample of recent cases to catch the category's prototype drifting, and triggers revision of the reference cases before the drift is baked in.
• Graded Membership Table — Lays out each case with its degree-of-membership score and typicality zone, making the category's centre — and the handling each zone gets — visible at a glance.
• Near-Miss Comparison Set — Sharpens a category's boundary with minimal pairs — a genuine member set beside near-identical nonmembers that differ on the single feature that actually decides membership.
• Nearest-Neighbor or Exemplar Classifier — Classifies a new case by its similarity to stored labeled exemplars — no explicit rule, just which known cases it most resembles — and routes it by how confidently it lands.
• Positive / Negative Example Deck — A curated deck of clearly-labeled positive and negative examples — each carrying its rationale and the action it triggers — that installs a category's center and purpose in a new judge.
• Prototype Embedding Map — Projects examples into a spatial map so the category's center, its multiple sub-clusters, and how membership thins toward the edges become visible at a glance.
• Similarity Dimension Rubric — Names the dimensions along which resemblance to the prototype is judged, sets their weights (which can shift by context), and fences off the dimensions that must never count.
• Typicality Rating Exercise — Has people rate how typical each example is of a category, turning intuition into a graded ranking that surfaces the clearest anchors and the fuzzy middle.