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USGS · 70023559

Evaluation of mixed-population flood-frequency analysis

P.J. Murphy
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Abstract

A mixed population of flood flows was shown to cause quality-of-fit problems if a single-population flood-frequency distribution was used to describe the flood data. The three populations in this mix were "ordinary," tropical cyclone, and ice-jam-release floods. Parametric descriptions of the single and separated flood populations were evaluated using probability-plot correlation-coefficient tests. These tests quantified how well the flood-probability distributions agreed with plotting-position descriptions of the data and quantified the differences due to the mixed-population analysis. High outliers caused the high skewness found in the single- population analyses. The tropical cyclone component was underestimated by single-population analyses at gauging stations in Massachusetts that had little data.

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BibTeXRIS

P.J. Murphy. 2001. Evaluation of mixed-population flood-frequency analysis. https://doi.org/10.1061/(asce)1084-0699(2001)6%3A1(62)

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