what makes a linear relationship more likely to be stationary? why would cointegration test make sense do stationary processes need cointegration why is it necessary to study the cointegration of two time series? what makes sense to test for cointegration what makes cointegration test valid does cointegration make sense? what is the lag between linear and cointegrate when does cointegration happen in a time series do stationary processes make sense why would it make sense to test for cointegration between two time series does cointegration test for linearity when does cointegration take place what makes sense when two time series are stationary does cointegration test is there a cointegration between time series is cointegration stationary does it make sense to test cointegration why does it make sense to cointegrate two time series? why is cointegration useful