REML analysis of linear mixed models


The REML algorithm allows you to analyse linear mixed models i.e. linear models that can contain both fixed and random effects. In some applications these are known as "multi-level" models. It can thus be used to analyse unbalanced designs with several error terms (which cannot be analysed by ANOVA). It can also fit random correlation models to describe the covariances between random effects as can arise, for example, in the analysis of repeated measurements or spatial data.


REML
fits a variance-component model by residual (or restricted) maximum likelihood

VCOMPONENTS
defines the model for REML

VCYCLE
controls advanced aspects of the REML algorithm

VDISPLAY
displays further output from a REML analysis

VKEEP
copies information from a REML analysis into GenStat data structures

VSTRUCTURE
defines a variance structure for random effects in a REML model

VPEDIGREE
generates an inverse relationship matrix for use when fitting animal or plant breeding models by REML

VPREDICT
forms predictions from a REML model

VRESIDUAL
defines the residual term for a REML model

VSTATUS
prints the current model settings for REML


There are several procedures that may be useful during a REML analysis.


FCONTRASTS
modifies a model formula to contain contrasts of factors

FDIALLEL
forms the components of a diallel model for REML or regression

VAIC
calculates the Akaike and Schwarz information coefficients for REML

VFUNCTION
calculates functions of variance components from a REML analysis

VGRAPH
plots one- or two-way tables of means from REML

VLSD
prints approximate least significant differences for REML means

VMCOMPARISON
performs pairwise comparisons between REML means

VPLOT
plots residuals from a REML analysis


There is also a suite of procedures that use REML to estimate QTLs from single environment or multi-environment trials


DQMAP
displays a genetic map

DQMKSCORES
plots a grid of marker scores for genotypes and indicates missing data

DQMQTLSCAN
plots the results of a genome-wide scan for QTL effects in multi-environment trials

DQSQTLSCAN
plots the results of a genome-wide scan for QTL effects in single-environment trials

QCANDIDATES
selects QTLs on the basis of a test statistic profile along the genome

QDESCRIBE
prints summary statistics of genotypes

QEXPORT
exports genotypic and phenotypic data for QTL analysis

QIBDPROBABILITIES
reads molecular marker data and calculates IBD probabilities

QIMPORT
imports genotypic and phenotypic data for QTL analysis

QMBACKSELECT
performs a QTL backward selection for loci in multi-environment trials

QMESTIMATE
calculates QTL effects in multi-environment trials

QMQTLSCAN
performs a genome-wide scan for QTL effects (Simple and Composite Mapping) in multi-environment trials

QSBACKSELECT
performs a backward selection for loci in single-environment trials

QSESTIMATE
calculates QTL effects in single-environment trials

QSQTLSCAN
performs a genome-wide scan for QTL effects (Simple and Composite Mapping) in single-environment trials

QTHRESHOLD
calculates a threshold to identify a significant QTL

VGESELECT
selects the best variance-covariance model for a set of environments