small.bins : a vector of length I+1 with the small bin limits.
ui : the I midpoints of the small bins.
delta : width of the small bins.
I : the number of small bins.
B.i : a matrix of dim I by K with the B-spline basis evaluated at the small bin midpoints.
K : number of B-splines in the basis.
knots : equidistant knots supporting the B-splines basis.
Big.bins : vector of length J+1 with the limits of the J big bins containing the data used to produce the tabulated statistics.
freq.j : the number of data observed within each big bin.
m.j : a matrix of dim J by 4 giving the first 4 sample central moments within each big bin.
J : the number of big bins.
small.to.big : a vector of length I indicating to what big bin each element of ui belongs.