Reanalysis of subjective crackle ratings using a logistic curve fit

Abstract

Prior work has shown a robust relationship between crackle from high-performance jets and the skewness of the distribution of the first time derivative of the pressure waveform; however, prior efforts have characterized this relationship in terms of a linear relationship between the log of the derivative skewness and the category scaling responses. While the relationship is linear over important portions of its range, the use of a logistic curve fit more fully captures the characteristics of the relationship between log first time derivative skewness and category scaling relationship including implied non-negativity, and saturation. Accordingly, a logistic curve is fit to these data, and the residual magnitudes are compared between the two fitting approaches.