what is the unit root for cointegrated equation which variable are cointegrated what unit of test is used for cointegrated which variable is integrated at first difference adf test for cointegration what is a cointegrated series used for what is cointegration in adf what is used to verify if an equation is cointegrated how is cointegrated a variable used in adf what is the unit root of a cointegration test? when to check for cointegration what if you use adf unit test? if a variable is cointegrated does it always have an intercept? which variable can be cointegrated? what is the unit root value for the residual variable if the two series are cointegrated what is the test which variable is cointegrated why is a series of variables integrated adf? what is the value of the first difference in a unit root what is unit root of cointegrating variable