%0 Journal Article %T Polynomial Regressions and Nonsense Inference %A Daniel Ventosa-Santaul¨¤ria %A Carlos Vladimir Rodr¨ªguez-Caballero %J Econometrics %D 2013 %I MDPI AG %R 10.3390/econometrics1030236 %X Polynomial specifications are widely used, not only in applied economics, but also in epidemiology, physics, political analysis and psychology, just to mention a few examples. In many cases, the data employed to estimate such specifications are time series that may exhibit stochastic nonstationary behavior. We extend Phillips¡¯ results (Phillips, P. Understanding spurious regressions in econometrics. J. Econom. 1986, 33, 311¨C340.) by proving that an inference drawn from polynomial specifications, under stochastic nonstationarity, is misleading unless the variables cointegrate. We use a generalized polynomial specification as a vehicle to study its asymptotic and finite-sample properties. Our results, therefore, lead to a call to be cautious whenever practitioners estimate polynomial regressions. %K polynomial regression %K misleading inference %K integrated processes %U http://www.mdpi.com/2225-1146/1/3/236