title: Does a univariate ARIMA model become mulitvariate when I add exogenous variabels to the function? I did this in r with the function xreg
body: <p>Does a univariate ARIMA model become mulitvariate when I add exogenous variabels to the function? I did this in r with the function xreg.</p>
  
  <p>For example: <code>fitwithtwoexfactors = arima(futoilrtn,order=c(0,0,1), xreg=exogenous)</code></p>
  
  <p>exogenous is a data frame with two columns.</p>