Question

What should be the variable type to do a panel in r?

Answer 1

have a panel dataset where hospitals are followed over time from 2004 to 2010 every two years. The data is in Stata but I take it to R. Initially the variables year (2004, 2006, 2008, 2010) and t(1=2004, 2=2006 and so on) are in integer but later I convert them into factors as follows:

data$year <- factor(data$year)


and similarly for t time variable as well.