![Regression with inequality constraints on parameters](https://blogs.sas.com/content/iml/files/2020/09/restrictedReg3-614x336.png)
A previous article discussed how to solve regression problems in which the parameters are constrained to be a specified constant (such as B1 = 1) or are restricted to obey a linear equation such as B4 = –2*B2. In SAS, you can use the RESTRICT statement in PROC REG to