ThispaperconstructsasetofconfidenceregionsofparametersintermsofstatisticalcurvaturesforAR(q)nonlinearregressionmodels.Thegeometricframeworksareproposedforthemodel.Thenseveralconfidenceregionsforparametersandparametersubsetsintermsofstatisticalcurvaturesaregivenbasedonthelikelihoodratiostatisticsandscorestatistics.Severalpreviousresults,,suchas[1]and[2]areextendedtoAR(q)nonlinearregressionmodels.