Analysis of Variance of Traffic Usage Data

Procedures are developed and illustrated by application to real usage data of analysis of variance techniques for measuring components of variance in the data due to trend and arbitrary random variability in usage of equipment in a group as a whole. The usage data are obtained by periodic scanning of the equipment group at fixed intervals. Procedures for fitting the Polya distribution to the data are presented. Fitted Polya distributions are used to estimate the effects of trend on blocking. The procedures are extended to measuring and estimating the effects on blocking of day-to-day traffic variation and are illustrated by application to real usage data. A procedure is presented for adjusting estimates of variance for autocorrelation due to the usage measurement procedure and call holding times. The adjustment procedure is based on incomplete research and is, therefore, tentative. The effects of using a variance-stabilizing transformation of the data are shown. Other areas of application of the theory and procedures are discussed.