Record Display for the EPA National Library Catalog


Main Title Parameterization of Observed Hydrographs.
Author Downe, Richard N. ;
CORP Author Vermont Univ., Burlington. Dept. of Civil Engineering.
Year Published 1970
Report Number Rept. no. ;1; OWRR-A-008-VT; 03665,; A-008-VT(1)
Stock Number PB-196 899
Additional Subjects ( Hydrology ; Statistical analysis) ; Least squares method ; Curve fitting ; Computer programming ; Regression analysis ; Flood forecasting ; Flood routing ; Watersheds ; Gamma function ; Data processing ; Mathematical models ; Vermont ;
Library Call Number Additional Info Location Last
NTIS  PB-196 899 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 65p
A simple transformation of the incomplete gamma function was used to describe single-peaked hydrographs. A weighted least-squares method produces a forced fit of the crest portion of the observed hydrograph. In addition to determining the parameters of the fit with minimum squared deviations, the computer plots the original and fitted hydrographs and calculates statistics to assist in making an objective decision as to the hydrological goodness-of-fit. A good least-squares fit does not necessarily result in a good hydrologic fit. Judgment of goodness-of-fit on the central portion of the hydrograph is aided by a significance test which combines the number of data points with features of the ocular fit (balancing of volumes and minimizing of deviations). The complete goodness-of-fit test assumes that: (1) the assumed model is correct; and (2) if the model is a correct one, there is a close mathematical relation between the observed and fitted data. (WRSIC Abstract).