Statistical treatment of rain gauge calibration data

This paper describes the statistical treatment of the calibration data of the capacitance gauges used for measurement of rain rates in the rain gauge network set up in a 160 square kilometer area surrounding Crawford Hill, Holmdel, New Jersey. The expression R = αe
^−βf
, where R is the rain rate in millimeters per hour, f is the frequency of the rain gauge oscillator, and α and β are fitted coefficients, allows calibration curves to be developed for all 99 of the devices in the system with an overall equivalent standard error of 7.3 millimeters per hour. This paper discusses the distribution of parameters and residuals and gives a refinement which corrects for a fitting bias.