1. A method of noise reduction in data regarding parameter values comprising the steps of: making a series of measurements of parameter values at times separated by predetermined time intervals; forming an array of measurements of parameter values comprising plural successive measurements of parameter values; performing a plurality n of successive wavelet transforms on the array of measurements of parameter values to produce an array of coefficients; comparing the values of the array of coefficients to a threshold value and, selectively changing the values of said coefficients based on their relationship to the threshold, to produce an array of filtered coefficients; and performing n successive inverse wavelet transforms on the array of filtered coefficients to produce an array of filtered measurements.