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Effective record length for the T-year event

Gary D. Tasker
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Abstract

The effect of serial dependence on the reliability of an estimate of the T -yr. event is of importance in hydrology because design decisions are based upon the estimate. In this paper the reliability of estimates of the T -yr. event from two common distributions is given as a function of number of observations and lag-one serial correlation coefficient for T = 2, 10, 20, 50, and 100 yr. A lag-one autoregressive model is assumed with either a normal or Pearson Type-III disturbance term. Results indicate that, if observations are serially correlated, the effective record length should be used to estimate the discharge associated with the expected exceedance probability.

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Gary D. Tasker. 1983. Effective record length for the T-year event. https://doi.org/10.1016/0022-1694(83)90059-8

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