Shin, Dong Wan; Joon Kim, Han; Jhee, Won-Chul - In: Statistics & Probability Letters 77 (2007) 1, pp. 75-82
For seemingly unrelated regression (SUR) models with integrated regressors, two sufficient conditions are identified, under which the ordinary least-squares estimator (OLSE) is asymptotically efficient. The first condition is that every pair of regressor processes are cointegrated in a specific...