%wor Timing Semantics

Status: Current Last modified: 2026-08-30 15:23 EDT

Purpose

%wor is a timing sidecar over a named subset of main-tier word slots. It is not an independent lexical transcript and it is not a structural dependent-tier alignment like %mor, %pho, or %sin.

The main tier owns lexical identity. %wor contributes an optional inline media bullet for each selected position. The visible word printed on %wor is display material and optional corroborating evidence. It can prevent stale timing reuse, but it never supplies lexical identity.

Actual timing presence is a separate typed question from correspondence. WorTier::timing_evidence() returns Absent or a RecordedWorTiming carrying the first real word-level bullet. Media validation uses this state directly. Equal counts with no bullets are not timing evidence, while a real bullet remains timing evidence even when counts drift. Alignment processing is not required to observe a bullet already in the typed CHAT model. A %wor tier cannot carry a trailing tier-level bullet: the grammar does not permit that state, and WorTier cannot construct or serialize it.

Current membership policy

The canonical policy is FilteredLexicalV1. A typed WorMainTierProjection is its single traversal owner. Both %wor generation and timing binding consume that projection, so a policy edit cannot update one path and leave the other behind.

This policy is explicit because the meaning of one-to-one correspondence depends on which main-tier items count. A future research policy must receive a new name and separate evaluation. It must not silently change FilteredLexicalV1.

Typed binding and correspondence states

Consumers call bind_wor_timing(main, wor). The data state is one of:

• Missing: no %wor tier exists. This is distinct from a present empty tier.
• Drifted: the selected main-tier slot count differs from the physical %wor word-entry count. No positional slots are exposed.
• CountMatched: counts match under the named policy. This state permits a positional comparison but exposes no timing slots. Equal counts alone do not prove that a parsed legacy tier and the current main tier share origin.

Consumers pass CountMatched to corroborate_wor_timing. The next state is:

• Uncorroborated: one or more %wor display tokens differ from the canonical display tokens generated from the current main-tier projection. The state exposes exhaustive mismatch diagnostics but no timing slots.
• Corroborated: every display token matches the canonical generated token at its count-matched position. Only this state exposes positional timing slots.

Each corroborated slot has:

• a borrowed typed main-tier Word and its cleaned_text, which remain the only lexical identity;
• Timed(WorRecordedInterval) when the corresponding %wor entry has an inline bullet;
• Unaligned when the entry exists but has no inline bullet.

This transition detects same-count edits when they change at least one canonical display token. It cannot establish immutable common origin: repeated tokens can be exchanged invisibly, and CHAT does not carry a generation identifier. The state is therefore named Corroborated, not Aligned or Proven.

Temporal sequence transition

Lexical corroboration is necessary but not sufficient for algorithms that need a word-timing hull. A corroborated tier may still contain an untimed slot, a zero or backwards interval, or adjacent word intervals that overlap.

Consumers call assess_wor_timing_sequence(corroborated) for the next checked transition. It returns one of:

• Empty: the sidecar is present and corroborated, but the membership policy selected no words. There is no hull.
• Rejected: the binding contains one or more Unaligned or NonPositiveInterval issues. The diagnostic state exposes typed slot indices and numeric evidence, but no partial hull.
• Complete: every selected word has a positive interval. Only this state exposes borrowed main words paired with typed recorded intervals, a min/max WorTimingHull, and every typed adjacency relation.

Each adjacency is Gap, Touching, Overlap, or BackwardStart. Overlap and backwards starts remain visible evidence, but do not erase a hull that is still mechanically defined by the recorded extrema. An algorithm that requires common origin, acoustic accuracy, non-overlap, or monotonic starts must state and enforce that later policy over additional evidence or the relation types.

The assessment transition is infallible because its control flow makes the remaining construction failure unrepresentable. An empty binding returns Empty. A nonempty binding assesses the first slot before it can construct a complete accumulator. A first-slot failure starts a rejected accumulator; a first complete slot is the required seed for the hull. No caller or internal branch can construct a nonempty complete sequence without that seed.

WorSlotIndex, WorMediaOffsetMs, WorDurationMs, and WorTimingHull have private constructors. A caller cannot mint an index for an unrelated tier, present arithmetic as a recorded media coordinate, or label arbitrary offsets as a hull that passed chatter’s sequence assessment. Recorded offsets and the duration derived by subtraction remain different types.

The complete state does not return the original Bullet. Returning it would reopen direct access to raw integer fields and let every consumer rebuild the same loose arithmetic. WorRecordedInterval is the only timing surface after binding.

This is deliberately stricter than ordinary CHAT validation. CHAT can retain legacy or partially aligned data. A timing-consuming algorithm needs an explicit admission contract and must not infer one from the fact that the file parsed.

The count types for the main sequence and the physical %wor sequence are different newtypes. Callers cannot swap them accidentally. Constructors for the proof states and counts are private.

The count-matched state is deliberately named for the fact it actually proves. It does not claim common origin and it cannot expose timing. The corroborated state is also deliberately limited: canonical display equality provides useful evidence against stale reuse, but serialized CHAT carries no immutable generation identity. Acoustic or common-origin qualification requires later evidence and a different state.

The binding borrows both typed sequences until correspondence is decided. Corroboration retains main-tier words as lexical identity and copies the two recorded media offsets into private-constructor coordinate types. It does not clone a temporary generated %wor tier or reduce structured lexical identity to a string.

The main-tier projection owns word and separator selection in source order. Its constructor is private to MainTier::wor_projection(). Generation derives the visible tier from this capability, and binding consumes the same capability to obtain lexical slots. There is no independent counter or generator whose agreement must be tested at runtime. Count drift between a parsed legacy tier and its main tier remains a real Drifted data state.

flowchart LR
    Main[Typed MainTier] --> Projection[WorMainTierProjection]
    Projection --> Generated[Derived WorTier]
    Projection --> Binding{Timing binding}
    Parsed[Parsed legacy WorTier] --> Binding
    Binding --> Missing
    Binding --> Drifted
    Binding --> CountMatched
    CountMatched --> Correspondence{Canonical token correspondence}
    Correspondence --> Uncorroborated
    Correspondence --> Corroborated
    Corroborated --> Sequence{Sequence assessment}
    Sequence --> Empty
    Sequence --> Rejected
    Sequence --> Complete

Generation and parsing

For newly generated data, word timings are embedded on typed main-tier words. MainTier::generate_wor_tier() derives the visible sidecar from those words. It copies main-tier cleaned_text for display and copies the inline bullets for timing.

For parsed legacy CHAT, the main tier and %wor are separate AST values. A consumer must use the binding transition and then lexical corroboration before recovering timing by position. Different display words produce an Uncorroborated state. They do not replace main-tier lexical identity and do not make the CHAT file invalid.

Validation versus evidence admission

A drifted %wor tier does not make a legacy CHAT file invalid. Editors may change the main tier without immediately rerunning forced alignment, and older corpora used different membership conventions.

Evidence-consuming algorithms have a stricter contract. They must refuse Missing, Drifted, or Uncorroborated when their operation requires word timing. They must also decide whether Unaligned slots, empty intervals, nonmonotonic intervals, or timings outside the main bullet are acceptable for that specific operation. Structural and lexical admission do not prove acoustic accuracy.

Temporal completeness does not prove acoustic accuracy either. It establishes only coverage, positive duration, a min/max location hull, and explicit adjacency geometry. The aligner may still place a perfectly well-formed onset or offset too early or too late. Model score, boundary origin, human calibration, and downstream merge outcome belong to a later evidence layer.

Research boundary

The abandoned goal of timing every spoken main-tier item remains a legitimate research question. It is not a correction to current semantics until the membership question has been specified and evaluated. In particular, fragments, nonwords, untranscribed material, interactional sounds, retraces, and editorial replacements need explicit rules.

Confidence, acoustic quality, and provenance should remain typed internal evidence attached to a binding or downstream decision. Chatter must not revive public %xalign clutter as a side effect. A public %wor tier remains a derived view unless TalkBank deliberately adopts a new visible format.

Alternative policies and acoustic qualification should be tested against immutable evidence artifacts before changing corpus output. The relevant questions include:

• whether the proposed policy reduces human correction time;
• whether every additional slot can receive defensible acoustic boundaries;
• whether changed timing improves MichiganChild and IISRP merge placement;
• whether confidence and provenance improve decisions without becoming public transcript clutter;
• whether a new policy can coexist with legacy %wor data without ambiguous automatic reinterpretation.

Release boundary

Analysis projects that pin a released chatter tag must adopt the binding API only after that chatter release is cut. They must not switch to a live path dependency to test this code. Until then, they may reproduce current membership with the released typed generator, but the first post-release change should replace that local pairing with bind_wor_timing followed by corroborate_wor_timing. Its regression evidence must show both that a same-count token edit is refused and that %wor text never becomes lexical authority.

Downstream code that currently derives a main-tier bullet by manually checking every %wor word and taking the minimum and maximum timing should then use the sequence transition, WorTimingHull, and typed adjacency relations. This removes the repeated loose procedure while preserving the important rule that one untimed word cannot claim a complete child-utterance span. Compatibility with a downstream policy must be measured before replacement because the new API reports overlap and backwards starts instead of silently ignoring them.

This page last changed: 2026-08-30 (commit 733da964). The whole book last changed: 2026-09-15 (commit bb4bef82).