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    Run an event study on market reactions

    Measure abnormal and cumulative abnormal returns around an event versus a benchmark, using stored daily prices and a stated estimation window.

    How did the stock react to the event, beyond the market move?

    An event study estimates normal returns from a pre-event window, then measures abnormal returns (actual − expected) around the event. Cumulating them over the event window gives the reaction attributable to the event.

    What you see in Market Ontology

    The live product, read-only. Your own work opens here after checkout.

    Event Studies screen in Market Ontology
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    What opens after checkout

    Abnormal-return study with methodology and diagnostics, built from the details above and saved to your account in Market Ontology.

    You get
    Abnormal-return study with methodology and diagnostics
    Opens in
    Market Ontology
    Built from
    Ticker, event date, windows, benchmark
    Orders
    None; nothing is sent on your behalf

    Method

    • — Expected return from a market model fitted over an estimation window (e.g. days −250 to −30).
    • — Abnormal return AR = actual − (α + β × market return); CAR = sum of AR over the event window.
    • — Significance from the estimation-window residual standard deviation.

    Limits

    Overlapping news in the window contaminates results; single-stock studies carry wide confidence intervals.

    Updated 2026-10-15

    Questions

    What is a cumulative abnormal return?
    The sum of daily returns in excess of the model's expectation across the event window.