Hi @VB : It's hard to know what is going on without: seeing your data, knowing what your goals are, knowing how the data were acquired etc. But...R^2=1, no p-values etc. means you've fit the points exactly (connected the points exactly via your quadratic model).In that case, there is no error; so there can be no RMSE, p-values, leverage plots (observed vs predicted plot), etc. Can you share more information?