onlineregression15:   Hyperbolic regression (intensity-duration regression)    ⇒   i = f(tr-1) Formulas 1/i = (tr/a) + (b/a)              y = α + βx α = b/a        x = tr        β = 1/a        y = 1/i β = [Σ(xy)-(ΣxΣy)/n]/{Σ(x2)-[(Σx)2/n]} α = [Σy-(βΣx)]/n Reference Ponce, V. M. 1989. Engineering Hydrology, Principles and Practices. Prentice Hall, pages 246-248. Return SAMPLE INPUT DATA: Array size n:   7 Paired values of arrays y and x (you can cut and paste sample arrays into form): i:     8,5,4,2.5,1.5,1.0,0.8 tr:     5,10,15,30,60,120,180 SAMPLE OUTPUT: a = 155.702            b = 26.5632 Thank you for running onlineregression15.   Please call again.   [070418]