lower than the threshold. Accepted values include 'left' and 'right'. If it sets to NULL, the missing values will be placed in a separate bin.</p></dd>


<dt>stop_limit</dt>
<dd><p>Stop binning segmentation when information value gain ratio less than the 'stop_limit' if using tree method; or stop binning merge when the chi-square of each neighbor bins are larger than the threshold under significance level of 'stop_limit' and freedom degree of 1 if using chimerge method. Accepted range: 0-0.5; Defaults to 0.