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 |
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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, for example, to define the model, to produce additional output or for other REML-based analyses.
FCONTRASTS |
modifies a model formula to contain contrasts of factors |
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FDIALLEL |
forms the components of a diallel model for REML or regression |
F2DRESIDUALVARIOGRAM |
calculates and plots a 2-dimensional variogram from a 2-dimensional array of residuals |
VAIC |
calculates the Akaike and Schwarz (Bayesian) information coefficients for REML |
VALLSUBSETS |
fits all subsets of the fixed terms in a REML analysis |
VAYPARALLEL |
does the same REML analysis for several y-variates, and collates the output |
VBOOTSTRAP |
performs a parametric bootstrap of the fixed effects in a REML analysis |
VCRITICAL |
uses a parametric bootstrap to estimate critical values for a fixed term in a REML analysis |
VCHECK |
checks standardized residuals from a REML analysis |
VDEFFECTS |
plots one- or two-way tables of effects estimated in a REML analysis |
VDFIELDRESIDUALS |
display residuals from a REML analysis in field layout |
VFIXEDTESTS |
saves fixed tests from a REML analysis |
VFLC |
performs an F-test of random effects in a linear mixed model based on linear combinations of the responses, i.e. an FLC test |
VFPEDIGREE |
checks and prepares pedigree information from several factors, for use by VPEDIGREE and REML |
VFRESIDUALS |
obtains residuals, fitted values and their standard errors from a REML analysis |
VFUNCTION |
calculates functions of variance components from a REML analysis |
VGRAPH |
plots tables of means from REML |
VHERITABILITY |
calculates generalized heritability for a random term in a REML analysis |
VLSD |
prints approximate least significant differences for REML means |
VMCOMPARISON |
performs pairwise comparisons between REML means |
VMETA |
performs a multi-treatment meta analysis using summary results from individual experiments |
VPLOT |
plots residuals from a REML analysis |
VPOWER |
uses a parametric bootstrap to estimate the power (probability of detection) for terms in a REML analysis |
VRACCUMULATE |
forms a summary accumulating the results of a sequence of REML random models |
VRCHECK |
checks effects of a random term in a REML analysis |
VRMETAMODEL |
forms the random model for a REML meta analysis |
VRPERMTEST |
performs permutation tests for random terms in REML analysis |
VRFIT |
fits terms from a REML fixed model in a Genstat regression |
VRADD |
adds terms from a REML fixed model into a Genstat regression |
VRDISPLAY |
displays output for a REML fixed model fitted in a Genstat regression |
VRDROP |
drops terms in a REML fixed model from a Genstat regression |
VRKEEP |
saves output for a REML fixed model fitted in a Genstat regression |
VRSETUP |
sets up Genstat regression to assess terms from a REML fixed model |
VRSWITCH |
adds or drops terms from a REML fixed model in a Genstat regression |
VRTRY |
tries the effect of adding and dropping individual terms from a REML fixed model in a Genstat regression |
VSAMPLESIZE |
estimates the replication to detect a fixed term or contrast in a REML analysis, using parametric bootstrap |
VSCREEN |
performs screening tests for fixed terms in a REML analysis |
VSOM |
analyses a simple REML variance components model for outliers using a variance shift outlier model |
VSPREADSHEET |
saves results from a REML analysis in a spreadsheet |
VSURFACE |
fits a 2-dimensional spline surface using REML , and estimates its extreme point |
VTCOMPARISONS |
calculates comparison contrasts within a multi-way table of predicted means from a REML analysis |
VUVCOVARIANCE |
forms the unit-by-unit variance-covariance matrix for specified variance components in a REML model |
There is also a suite of procedures to provide automatic selection of REML
random models for single trials, series of trials and meta analysis.
VABLOCKDESIGN |
analyses an incomplete-block design by REML , allowing automatic selection of random and spatial covariance models |
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VAROWCOLUMNDESIGN |
analyses a row-and-column design by REML , with automatic selection of the best random and spatial covariance model |
VALINEBYTESTER |
provides combinabilities and deviances for a line-by-tester trial analysed by VABLOCKDESIGN or VAROWCOLUMNDESIGN |
VLINEBYTESTER |
analyses a line-by-tester trial by REML |
VASERIES |
analyses a series of trials with incomplete-block or row-and-column designs by REML , automatically selecting the best random models |
VASDISPLAY |
displays further output from an analysis by VASERIES |
VASKEEP |
copies information from an analysis by VASERIES into Genstat data structures |
VASMEANS |
saves experiment × treatment means from analysis of a series of trials by VASERIES . |
VAMETA |
performs a REML meta analysis of a series of trials |
VFMODEL |
forms a model-definition structure for a REML analysis |
VFSTRUCTURE |
adds a covariance-structure definition to a REML model-definition structure |
VAOPTIONS |
defines options for the fitting of models by VARANDOM and associated procedures |
VARANDOM |
finds the best REML random model from a set of models defined by VFMODEL |
VARECOVER |
recovers when REML , is unable to fit a model, by simplifying the random model |