pisa.mean.pv uses five plausible values to calculate the mean achievement score and its standard error
pisa.mean.pv(pvlabel, by, data, export = FALSE, name = "output",
folder = getwd())
pisa.mean.pv returns a data frame with the mean values and standard errors.
The names of columns corresponding to the achievement plausible scores, for example, paste0("PV",1:10,"MATH").
The label for the grouping variable, usually the countries (i.e., by="IDCNTRYL"), but could be any other categorical variable.
An R object, normally a data frame.
A logical value. If TRUE, the output is exported to a file in comma-separated value format (.csv) that can be opened from LibreOffice or Excel.
The name of the exported file.
The folder where the exported file is located.
timss.mean.pv, pirls.mean.pv, piaac.mean.pv