piaac.reg returns a data frame with coefficients, standard errors and t-values. If "by" is specified, results are reported in a list.
If the "by" argument is set, then the returning object is of the class "intsvy.reg" with overloaded function plot().
Arguments
y
Label for dependent variable.
x
Data labels of independent variables.
by
The label for the grouping variable, usually the countries (i.e., by="CNTRYID"), but could be any other categorical variable.
data
An R object, normally a data frame, containing the data from PIAAC.
export
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.