Improvement of the Method using the Coefficient of Variation for Automatic Multi-segmentation Method of a Rating Curve

• DOI: 10.3741/jkwra.2015.48.10.807
• Publication Date: 2015-12-12T21:25:33Z
• Authors: Yeonsu Kim; Jeongyup Kim; Hyunuk An; Kwansue Jung
• Keywords: Rating curve; Homoscedasticity; Curve fitting; Coefficient of variation

In general, the water stage-discharge relationship curve is established based on assumptions of linearity and homoscedasticity. However, between stage discharge affected from geomorphological factors, which violates basic curve. order to reduce error due violations, divided into several sections manager's judgement considering change cross-sectional shape. this research, objective-splitting criteria proposed measured data without subjective decision. First, it assumed that coefficient variation follows normal distribution. Then, if newly calculated outside 95% confidential interval, divided. Namely, groups by characteristics reasonable provided for establishing a multi-segmented rating To validate method, was applied generated three artificial power functions. addition, confirm applicability Muju gauging station Sangegyo station. As result, found automatically improves accuracy extrapolation Finally, through residual analysis using Shapiro-Wilk normality test, confirmed tends follow