Calculate the rTPQuar, defined in Andersen et al. (2012).
Assume there are \(N\) equispaced returns \(r_{t,i}\) in period \(t\), \(i=1, \ldots,N\). Then, the rTPQuar is given by
$$
\mbox{rTPQuar}_{t}=N\frac{N}{N-2} \left(\frac{\Gamma \left(0.5\right)}{ 2^{2/3}\Gamma \left(7/6\right)} \right)^{3} \sum_{i=3}^{N} \mbox({|r_{t,i}|}^{4/3} {|r_{t,i-1}|}^{4/3} {|r_{t,i-2}|}^{4/3})
$$