Hello,
I have been trying to plot interaction effects using panel data with fixed effects but I get this error;
Error in (function (classes, fdef, mtable):unable to find an inherited method for function ‘sim’ for signature ‘"plm"’
Here is my code;
#>Fixed effect regression.
model2 <- plm(conschng~ DPC + SI + DPC*SI + lag(gdppc) + lag(unemrate) + lag(deprate) +
lag(infrate),
data = panelD,
index = c("Country","Period"),
model = "within",
effect = "individual")
#>plotting interaction effects
'''interplot(m=model2,var1 ="DPC",var2="SI") +
ggtitle("Estimated effect of SI for different levels of DPC") +
xlab("Level of DPC, Low --> High") +
ylab("Estimated effect of SI")+
geom_hline(yintercept = 0,linetype="dashed")'''
Any one to help me fix this error.
Thanks