Probability distribution function of the observed EW_Jo395 (black histogram). The left panel shows the best-fit D₂ model and its 68% confidence interval with the red line and area, respectively. The best-fit parameters are labeled in the panel. The purple line and area show the median distribution and its 68% confidence interval obtained from 5000 random samples extracted from D₂ and affected by the same uncertainties, σ_EW, as the observations. The right panel is similar to the left panel but for the baseline model, D₀.