stability_variance calculate variance of a genotype across environments.
stability_variance(data, trait, genotype, environment, unit.correct = FALSE)a dataframe containing trait, genotype and environment.
colname of a column containing a numeric vector of interested trait to be analyzed.
colname of a column containing a character or factor vector labeling different genotypic varieties.
colname of a column containing a character or factor vector labeling different environments.
logical, default is FALSE, returning the stability index with unit equals to squared unit of trait; when TRUE, returning stability index with the unit as same as unit of trait.#'
a data table with stability variance
Stability variance (Shukla, 1972) is calculatd based on lindear combination of ecovalence and mean square of genotype-environment interaction. Variety with low stability variance is considered as stable. Negative values of stability variance is replaced with 0. Equation of stability variance can be found in vignette file.
Shukla GK (1972). “Some statistical aspects of partitioning genotype environmental components of variability.” Heredity, 29(2), 237--245.
data(Data)
stability.variance <- stability_variance(
data = Data,
trait = "Yield",
genotype = "Genotype",
environment = "Environment")