I was able to incorporate Dummy2008 into the regression model, but including all four dummies resulted in the error below. How do I code the four dummy variables so that I can include all of them in the model?
X2 = [CPI IP Tbill Dummy2008 Dummy2009 Dummy 2010 Dummy 2011];
Error using horzcat
Dimensions of arrays being concatenated are not consistent.