Bortkiewicz on Chain Indices and Irving Fisher's Reversal Tests, A Historical Note and a Disapproval of the Time Reversal Test

Ladislaus von Bortkiewicz has criticized chain indices and Irving Fisher's time and factor reversal tests. However, his arguments (published in German articles) though well ahead of his time and still relevant today are widely fallen in oblivion. He was not the only German statistician who criticized Fisher' approach but the first who extensively and successfully used mathematics to substantiate it and to derive a formula for the "chain drift". We present his ideas together with some own arguments against the time reversal test. To study Bortkiewicz's and other criticisms of Fisher's reversal tests and chain indices remains worthwhile, because reference to the time reversal test is still unshakably popular today and it only recently became mandatory to compile chain indices in official statistics.