Correlation coefficient analysis for: (a) the ionization front radii and projected separation relation; (b) the ionization front radii and UV radiation relation; (c) mass-loss rate and UV radiation relation. The violet histogram corresponds to the bootstrapped randomized x-axis values; the dashed purple lines mark the 2σ ranges of the realizations. The blue histogram results from bootstrapping the y-axis values within the respective error bars, and the 1σ ranges of the bootstrap are shown with cyan line. We show that Spearman correlation coefficient for the measured data (orange line), which is outside 2σ of the randomized distribution.