Fitted Gaussian distribution of ΔpIC₅₀ (red) and ΔpK_i (black).

<p>The Gaussian distributions shown were fitted to all ΔpActivity values with an upper threshold ΔpActivity = 2.0. Standard deviations for the fitted Gaussian distributions are σ_pIC50 = 0.87 and σ_pKi = 0.69. Note that since the σ here is calculated from pairs of measurements each containing experimental uncertainty and other sources of variability, it has to be divided by √2 in order to obtain the true σ of the individual measurements <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061007#pone.0061007-Kramer2" target="_blank">[13]</a>.