Archive 2021

lmDiallel: a new R package to fit diallel models. The Griffing's models (1956)

Published at January 12, 2021 ·  10 min read

Diallel mating designs are often used by plant breeders to compare the possible crosses between a set of genotypes. In spite of such widespread usage, the process of data analysis in R is not yet strightforward and it is not clear which tool should be routinely used. We recently gave a small contribution by publishing a paper in Plant Breeding (Onofri et al., 2020 ), where we advocated the idea that models for diallel crosses are just a class of general linear models, that should be fit by Ordinary Least Squares (OLS) or REstricted Maximum Likelihood methods (REML)....

lmDiallel: a new R package to fit diallel models. The Hayman's model (type 2)

Published at January 5, 2021 ·  9 min read

This posts follows two other previously published posts, where we presented our new ‘lmDiallel’ package (see here) and showed how we can use it to fit the Hayman’s model type 1, as proposed in Hayman (1954) (see here). In this post, we will give a further example relating to another very widespread model from the same author, the Hayman’s model type 2. We apologise for some overlapping with previous posts: we think this is necessary so that each post can be read on its own....