---
title: "Extreme factor pairs"
method: GET
path: "/v1/factors/extreme-pairs"
---

# Extreme factor pairs

`GET /v1/factors/extreme-pairs`

## Request

- Base URL: `https://api.turos.app`
- URL: `https://api.turos.app/v1/factors/extreme-pairs`
- Auth: one of:
  - API key in header `x-api-key`
  - HTTP bearer

Return factor pairs ranked by unusual rolling spread divergence with direction, threshold, and trust metadata.

## Query parameters

- `factors` string
- `keys` string
- `category` string
- `window` '1d' | '5d' | '10d' | '21d' | '63d' | '126d' | '252d' | '1m' | '3m' | '6m' | '1y'
- `lookback` string
- `side` 'both' | 'factor1' | 'factor2' | 'flat'
- `direction` 'both' | 'factor1' | 'factor2' | 'flat'
- `sort` 'abs_z_score' | 'abs_spread_return'
- `min_z_score` number
- `limit` integer
- `response_mode` 'compact' | 'standard' | 'verbose'
- `include` string

## Response `200`

Successful response

- FactorExtremePairList
  - `object` 'list', required
  - `data` FactorExtremePair[], required
    - `dataAsOf` string
    - `freshnessStatus` 'fresh' | 'stale' | 'degraded' | 'unknown'
    - `methodologyVersion` string
    - `materializationVersion` string
    - `object` 'factor_extreme_pair', required
    - `responseMode` 'compact' | 'standard' | 'verbose': Projection used for this resource. compact is token-efficient for agents; standard and verbose retain fuller operational context.
    - `id` string, required
    - `rank` integer, required
    - `factor1` string, required
    - `factor2` string, required
    - `factor1Name` string, required
    - `factor2Name` string, required
    - `category1` string, required
    - `category2` string, required
    - `window` '1d' | '5d' | '10d' | '21d' | '63d' | '126d' | '252d', required
    - `lookback` string, required
    - `direction` 'factor1' | 'factor2' | 'flat', required
    - `sort` 'abs_z_score' | 'abs_spread_return', required
    - `score` number, required
    - `absZScore` number, required
    - `absSpreadReturn` number, required
    - `minAbsZScore` number, required
    - `isExtreme` boolean, required
    - `spreadReturn` number, required
    - `factor1Return` number, required
    - `factor2Return` number, required
    - `averageSpreadReturn` number, required
    - `spreadVolatility` number, required
    - `zScore` number, required
    - `spreadZScore` number, required
    - `meanReversionSignal` 'factor1_overextended' | 'factor2_overextended' | 'neutral', required
    - `meanReversionSummary` string, required
    - `windowStartDate` string, date, required
    - `windowEndDate` string, date, required
    - `pairHistory` object, required
    - `observationCount` integer, required
    - `rollingObservationCount` integer, required
    - `asOf` string, date-time, required
    - `provenance` ResponseMetadata
      - `source` string, required
      - `sourceLabel` string
      - `sourceAgency` string
      - `canonicality` string
      - `fallbackPolicy` string
      - `accessionNumber` string, nullable, required
      - `filingUrl` string, uri, required
      - `acceptedAt` string, nullable
      - `retrievedAt` string, required
      - `parserVersion` string, required
    - `freshness` FreshnessMetadata: Freshness of the record. For SEC filings, freshness measures the delay between SEC acceptance (`sourcePublishedAt`) and when the record became available in the API — not the age of the document. Statuses: `current` (recently published and available promptly), `archival` (an immutable historical document held in full; its availability delay is not a freshness signal), `degraded`/`stale` (a recently published filing that became available later than the freshness thresholds allow), `fresh` (continuously refreshed datasets recently observed at source), `unknown` (no timestamps). An old immutable filing is never `stale` simply because it was published long ago. `lagMs` is the publish-to-availability delay in milliseconds.
      - `status` 'fresh' | 'current' | 'archival' | 'stale' | 'degraded' | 'unknown', required
      - `asOf` string, required
      - `sourcePublishedAt` string, nullable
      - `lagMs` integer, nullable
    - `materialization` MaterializationMetadata
      - `parserVersion` string, required
      - `materializationVersion` string, required
    - `sourceRights` SourceRightsMetadata
      - `source` string, required
      - `sourceLabel` string
      - `posture` 'public_safe' | 'contract_gated' | 'internal_only' | 'inventory_only' | 'review_required', required
      - `publicAvailability` 'public' | 'contract_gated' | 'internal_only' | 'inventory_only', required
      - `contractStatus` 'approved' | 'review_required' | 'restricted' | 'prohibited' | 'expired', required
      - `restrictions` string[]
      - `notes` string, nullable
    - `methodology` MethodologyMetadata
      - `id` string, required
      - `version` string, required
      - `summary` string, required
      - `confidence` 'high' | 'medium' | 'low', required
      - `launchState` 'experimental' | 'beta' | 'ga', required
      - `inputs` string[]
      - `validation` object
    - `revision` RevisionMetadata
      - `sourcePublishedAt` string, nullable
      - `retrievedAt` string, required
      - `vintageId` string, nullable
      - `revisedFrom` string, nullable
    - `degradedState` DegradedState
      - `code` string, required
      - `message` string, required
      - `retryable` boolean, required
      - `missingCapabilities` string[]
      - `fallbackUsed` string[]
  - `hasMore` boolean, required
  - `nextCursor` string, nullable, required
  - `responseMode` 'compact' | 'standard' | 'verbose': Projection used for this resource. compact is token-efficient for agents; standard and verbose retain fuller operational context.
  - `include` string[]
  - `requestId` string
  - `traceparent` string

## Other responses

- `default`: Contract-aware error response

---

[API](https://skmtc.dev/turos/apis/turos-api.md) · [All operations](https://skmtc.dev/turos/apis/turos-api/llms.txt) · [OpenAPI document](https://skmtc.dev/turos/apis/turos-api/revisions/a68d3ec80a56?raw)