title: The analysis of the NSW wheat variety database. I. Modelling trial error variance.
abstract: The retrospective analysis of a large database on wheat variety testing in New South Wales (NSW) is considered. This analysis involved three key steps. Initially error variance heterogeneity is modelled, indicating significant differences in error variance due to trial location, year of trialling, sowing date and trial mean yield. The implication of this modelling for the estimaion of variance components is discussed.
authors.affiliation: Agricultural Research Institute, 2650, Wagga Wagga, NSW, Australia.
authors.forename: B R
authors.initials: BR
authors.lastname: Cullis
authors.forename: F M
authors.initials: FM
authors.lastname: Thomson
authors.forename: J A
authors.initials: JA
authors.lastname: Fisher
authors.forename: A R
authors.initials: AR
authors.lastname: Gilmour
authors.forename: R
authors.initials: R
authors.lastname: Thompson