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Glossary — prefix / query / context / answer (the context->answer mapping line)

updated: 2026-07-06

Canonical vocabulary for the context->answer-map experiments (#779, #810/#658 line, and successors). One first-use rule: context = prefix + query (the full model input).

Text objects

termdefinitionnotes
prefixeverything before the query: system prompt / persona / many-shot exemplar history / emptythe reusable, condition-defining part. The eval rig's "conditions" are its prefixes, so "within-condition r" = within-prefix
querythe user message / question
contextthe full model input: prefix + query, up to the assistant headerwhat generation conditions on ("the prompt" in API terms)
answerone sampled completion for a contextdecoding is stochastic (temp 1.0), so a context induces a distribution over answers; a rollout = one draw

Degenerate case: bare user prompts (e.g. the LMSYS corpus) have an empty prefix — apart from the chat template's constant default system prompt — so there context ~= query.

Vectors (all per layer, Qwen-2.5-7B: 28 layers x 3584 dims)

symbolnamedefinition
vCv_Ccontext vectoractivation at the last prompt token (the final newline of the assistant header) of ONE context
vPv_Pprefix vectora fixed prefix's context vectors averaged over many queries: vP=vˉCqv_P = \bar{v}_C^{\,q}
vAv_Aanswer vectormean activation over ONE answer's tokens (token-mean is intrinsic to vAv_A; no bar needed)
vˉAq\bar{v}_A^{\,q}behavior profilea prefix's answer vectors averaged over its queries (and rollouts) — the summary of the model's behavior under that prefix
rBr_Btrait direction (persona vector)per-trait direction from the mean-difference persona-vectors extraction (arXiv 2507.21509 recipe)

Aggregation modifiers

Mark averaging with an overbar naming the axis — "averaged" alone never says over what:

  • ˉq\bar{\cdot}^{\,q} — averaged over queries
  • ˉr\bar{\cdot}^{\,r} — averaged over rollouts (answer draws); e.g. single-draw targets vAv_A vs rollout-averaged targets vˉAr\bar{v}_A^{\,r}

Maps

namefit rowsdefinitionwhere
context map MM'one row per (context, answer)vAMvCv_A \approx M' v_C#779 (5000 LMSYS; 2400/trait trait-eliciting)
prefix map MMone row per prefix, both sides query-averagedvˉAqMvP\bar{v}_A^{\,q} \approx M v_Pthe earlier averaged experiment (#810/#658 line, 50 prefixes x 48 queries)

Same measurement at two aggregation levels: vPv_P is literally the query-average of a prefix's vCv_C's, and the behavior profile is the query-average of its vAv_A's.

Read-out levels (monitoring)

  • context-level read-out — monitor scored per single context (per-prompt monitoring)
  • prefix-level read-out — monitor averaged over a prefix's queries (the grouped/persona-level monitoring result; much easier: hallucination r 0.09 per-context -> 0.53 at prefix level)

Retired / ambiguous terms (do not use)

termwhy retireduse instead
"per-example map", "averaged map"ambiguous about the averaged axiscontext map / prefix map
"query-level map"reads as the query-marginal (average over prefixes per query), a different, unbuilt designcontext map
"query vector"collides with attention Q of QKV; misdescribes rows that carry a personacontext vector vCv_C
"exchange-level" / "instance-level" / "condition-level"superseded coinages from the naming discussioncontext-level / prefix-level
bare "averaged"never says over whatoverbar with the axis: ˉq\bar{\cdot}^{\,q}, ˉr\bar{\cdot}^{\,r}

Search-time note — retired aliases stay grep targets

The table above governs WRITING (do not use these terms). When SEARCHING for prior work, do the opposite: old task bodies, events, and follow-up labels still carry the retired vocabulary (e.g. #813's follow-up label per-example-vs-averaged-map), so grep the aliases alongside the canonical terms, separator-tolerant ([-_ ] between words): per[-_ ]example, averaged[-_ ]map, question[-_ ]averaged, query[-_ ]averaged, single[-_ ]context, query[-_ ]level, exchange[-_ ]level, instance[-_ ]level, condition[-_ ]level. This list is not closed: as the retired-terms table above gains rows, derive their grep patterns from the table and add them here. Full recipe: .claude/agents/research-pm.md § Negative-existence claims.