Define inter-occasion variability (IOV) into the dataset. A new variable of name 'colname' will be output into the dataset and will vary at each dose number according to the given distribution.
IOV(colname, distribution, doseNumbers = NULL)
an IOV object
name of the column that will be output in dataset
distribution
dose numbers, if provided, IOV is generated at these doses only. By default, IOV is generated for all doses.