Evaluation of Computed K-Indices with Orthogonalized SR Method
Kadokura, S.
Abstract
Orthogonalized SR Method' (OSM), one of the algorithms to derive K-indices, has been tested following the decision during IUGG (Vancouver) and IAGA (Exeter); by histograms of differences between hand-scaled and computed K-indices for seven observatories (Memambetsu, Hermanus, Crozet, Kerguelen, Nurmijarvi, Ottawa, and Sodankyla) from March 1985 to February 1986. The OSM achieves good results except histograms for Hermanus (HER); (1) total agreements are 60 -75%, (2) the occurrence of the differences larger than one unit is less than 2%. The wrong results for HER suggest wrong hand-scaling. It was revealed by analysis of multi-observatories data set that OSM, which is the optimal in the linear algorithms on the basis of statistical principle, is adequate for the algorithm to derive K-indices.
