Posterior probability distribution for the difference in the mean p parameter of the beta distributions fitted to the eccentricity distributions of planetary orbits in simple and multiple stars. Here ∆p = p_single − p_multiple, and θ_single = θ_multiple. The thick horizontal black line represents the 95% HDI (see text), while the black labels indicate the upper and lower values of the 95% HDI and the mean ∆p. The vertical green dotted line indicates the location of the null difference, while the percentages show the relative areas of the distribution at both sides of this line. This figure was created using a modified version of the software provided by Kruschke (2015).