Van Imhoff E
Math Popul Stud. 1994 Feb;4(3):197-203, 223. doi: 10.1080/08898489409525373.
"This paper provides a geometric-mean solution to the consistency problem of multidimensional demographic projection models, based on the constrained minimization of an entropy function. A comparison with the existing harmonic-mean solution yields many similarities and almost no differences....However, one major advantage of the geometric mean is that its corresponding distance function is firmly based on (information) theory." (SUMMARY IN FRE)