Empirical probability density functions P(n˜i), P(n˜iu) and P(n˜id) of daily price limit hitting probabilities n˜i, n˜iu and n˜id for individual stocks.

<p>The dots are empirical data, the black dash-dotted curves are the MLE fits to the truncated normal distribution in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0120312#pone.0120312.e004" target="_blank">Equation (2)</a>, and the black dash-dotted curves are the OLS fits to the truncated normal distribution. (a) All limit hits; (b) Price up limit hits; (c) Price down limit hits.