Abstract
We will place certain parts of the theory of statistical efficiency into the author's
operator trigonometry (1967), thereby providing new geometrical understanding of statistical efficiency. Important
earlier results of Bloomfield and Watson, Durbin and Kendall, Rao and Rao, will be so interpreted. For
example, worse case relative least squares efficiency corresponds to and is achieved by the maximal turning
antieigenvectors of the covariance matrix. Some little-known historical perspectives will also be exposed.
The overall view will be emphasized.