Function returns the rMPV, defined in Andersen et al. (2012).
Assume there is \(N\) equispaced returns in period \(t\). Let \(r_{t,i}\) be a return (with \(i=1, \ldots,N\)) in period \(t\).
Then, the rMPV is given by
$$
\mbox{rMPV}_{N}(m,p)= d_{m,p} \frac{N^{p/2}}{N-m+1} \sum_{i=1}^{N-m+1}|r_{t,i}|^{p/m} \ldots |r_{t,i+m-1}|^{p/m}
$$
in which
\(d_{m,p} = \mu_{p/m}^{-m}\):
\(m\): the window size of return blocks;
\(p\): the power of the variation;
and \(m\) > \(p/2\).