The optimal size of knots is chosen by a rule of thumb adapted from Rose (2015).
bw_bern(udata)
| udata | data. |
|---|
optimal order of the Bernstein polynimals.
The formula is $$max(1, round(n^(1/3) * exp(abs(rho)^(1/n)) * (abs(rho) + 0.1))),$$ where \(\rho\) is the empirical Spearman's rho of the data.