RE_cor {multinma}

Random effects structure

Description

Use RE_cor to generate the random effects correlation matrix, under the assumption of common heterogeneity variance (i.e. all within-study correlations are 0.5). Use which_RE to return a vector of IDs for the RE deltas (0 means no RE delta on this arm).

Usage

RE_cor(study, trt, contrast, type = c("reftrt", "blshift"))

which_RE(study, trt, contrast, type = c("reftrt", "blshift"))

Arguments

study

A vector of study IDs (integer, character, or factor)

trt

A factor vector of treatment codes (or coercible as such), with first level indicating the reference treatment

contrast

A logical vector, of the same length as study and trt, indicating whether the corresponding data are in contrast rather than arm format.

type

Character string, whether to generate RE structure under the "reference treatment" parameterisation, or the "baseline shift" parameterisation.

Value

For RE_cor(), a correlation matrix of dimension equal to the number of random effects deltas (excluding those that are set equal to zero).

For which_RE(), an integer vector of IDs indexing the rows and columns of the correlation matrix returned by RE_cor().

Examples

RE_cor(smoking$studyn, smoking$trtn, contrast = rep(FALSE, nrow(smoking)))
RE_cor(smoking$studyn, smoking$trtn, contrast = rep(FALSE, nrow(smoking)), type = "blshift")
which_RE(smoking$studyn, smoking$trtn, contrast = rep(FALSE, nrow(smoking)))
which_RE(smoking$studyn, smoking$trtn, contrast = rep(FALSE, nrow(smoking)), type = "blshift")