Waiting time for a new record after a fixed sample

ID: waiting-time-for-a-new-record-after-a-fixed-sample

For independent identically distributed observations with continuous cumulative distribution function , fix the maximum of the first observations and let be the first subsequent observation exceeding it. The probability integral transform gives density on . Conditional on , has a geometric distribution of parameter . Therefore
The masses sum to one, so the waiting time is finite almost surely, but the tail-sum formula for expectation gives . These conclusions require only continuity of , not a density or a strictly increasing distribution function.

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