d SJ7-2 st0125. Estimation of Nonstationary Heterogeneous... d Estimation of Nonstationary Heterogeneous Panels d by Edward F. Blackburne III, Sam Houston State University d Mark W. Frank, Sam Houston State University d Support: blackburne@@shsu.edu d After installation, type help ^xtpmg^ f st0125/xtpmg.ado f st0125/xtpmg.hlp f st0125/xtpmg_ml.ado f st0125/article.do