I have a dataset of two column values something like the one shown below. I need to predict the values of y for values of x greater than 60. The curve must follow the increasing trend it is shown till x=60.
I have tried polynomial regression and SVR but it declines for values greater than 60. I have tried to fit the curve y = alnx + b to this curve but the R2score is 0.94. What model can I train for this purpose, or how can I improve the R2score but regressing over an appropriate logarithmic function?
If you need extrapolation: Maybe try a symbolic regressor like gplearn. It tries out different combinations of functions based an a genetic algorithm from simple to complex. You can also set the allowed functions. I have never tried it though.
Or maybe a smoothing spline. Those can also extrapolate. Maybe LQSUnivariateSpline from scipy. There you can set the anchor points, which would probably allow you to get a better fit with less parameters (The fewer, the better it extrapolates).