An analyst compares the out-of-sample forecasting performance of three autoregressive models on the same dataset and summarizes the following information:

| Metric | Model 1 | Model 2 | Model 3 |

|-------------------------|---------|---------|---------|

| Root mean squared error | 3.20 | 1.55 | 1.05 |

| Order of autoregression | 1 | 2 | 3 |

Which of the models is most accurate?