Keep multiple clocks
Period end, event time, publication, database retrieval, market session, and correction time remain distinct fields.
Apply one as-of cutoff across filings, XBRL facts, earnings schedules, stock-news links, macro observations, and permitted market history. Later amendments and corrections remain separate versions instead of overwriting earlier inputs.
Point-in-time data stores at least two clocks: effective time describes the period or event, while known-at time describes when the record was available to the system. An as-of query returns the version visible before a chosen cutoff.
Period end, event time, publication, database retrieval, market session, and correction time remain distinct fields.
Later amendments and corrected values become new records with lineage rather than mutating the earlier research input.
An as-of cutoff applies to filings, facts, schedules, news references, macro observations, and any permitted market history in the dataset.
Collection start, source gaps, ingestion failures, and rights restrictions are explicit coverage states, not invisible absences.
Product boundary: Point-in-time modelling does not make a dataset magically complete. Quality still depends on the source's historical depth and when collection began, so DataCedar reports temporal coverage per stream.
curl "https://api.datacedar.com/v3/stocks/AAPL/events?as_of=2025-02-01T00:00:00Z&limit=100" \
-H "X-API-Key: $QUARTERTRACE_API_KEY"{
"data": [{
"event_type": "earnings_schedule",
"effective_at": "2025-02-27T21:00:00Z",
"known_at": "2025-01-20T14:12:00Z",
"version": 2,
"supersedes": "event_version_1"
}],
"as_of": "2025-02-01T00:00:00Z"
}Examples document the public contract and may use illustrative values or redacted identifiers. Availability fields and rights filters are authoritative for the active environment.
Choose the exact simulated decision timestamp and timezone.
Select only records whose known-at time is at or before that cutoff.
For each effective item, use the latest eligible version without deleting older versions.
Save the coverage snapshot, source runs, and schema version with the experiment.
A revenue value can describe a quarter ending in March, appear in a filing in May, enter a database minutes later, and be amended months afterward. Each timestamp answers a different question.
DataCedar keeps the economic or effective time separate from publication, retrieval, and known-at time. Backtests filter by availability and then analyze by the period the fact describes.
Many convenient APIs return the cleanest value known today. That is useful for current analysis but can leak restatements, schedule confirmations, corrected macro releases, and revised identifiers into historical training data.
DataCedar appends versions and records which observation supersedes another. An as-of query resolves only among versions that were actually knowable before the cutoff.
Known-at timestamps prevent future information leakage, while survivorship-bias controls require a historical security universe that includes names that later delisted or changed. A dataset can solve one problem and still fail the other.
DataCedar's security model retains issuer and symbol history, but actual delisted-market coverage depends on a permitted source. Coverage metadata makes that limitation visible rather than claiming a perfect universe.
The latest table is cleaner. The point-in-time table is the one a historical strategy could have used.
Look-ahead bias occurs when a historical test uses information that was not available at the simulated decision time, such as a later restatement or finalized schedule.
Build historical stock price and volume exports with explicit adjustments, coverage checks, symbol history, and event windows for reproducible backtesting.
Query permitted stock price and volume beside SEC filings, earnings events, point-in-time fundamentals, news references, macro data, and coverage metadata.
Query SEC filing metadata, primary documents, exhibits, XBRL facts, and amendments with accession-level provenance and known-at timestamps.
Query scheduled, confirmed, rescheduled, and completed earnings events with known-at history, source evidence, fiscal periods, and reaction windows.
Explorer is $0 with no card and a 1 request/second limit. Market history and transcript text appear only when an eligible source is active for the account.
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