In general, mathematical coupling occurs when one variable directly or indirectly contains the whole or part of another, and the two variables are then analysed using correlation or regression, 4 ...

We present a more general method which allows models to be constructed with multiple variables on both sides of an equation and which can be computed easily by using a spreadsheet program. The ...

The efficiency gain of seemingly unrelated regression (SUR) relative to OLS is a decreasing function of correlation of variables across equations. This article examines the efficiency gain for an ...