|visits||member for||2 years, 2 months|
|seen||Mar 31 at 17:00|
Output of NonlinearModelFit differs from the correct result
Why do you think "[..] the result should be 1.23...*t^0.6548 [..]" in the first place? The results you get for a non-linear fit depend on many factors, for instance the optimization/minimization algorithm used, starting values, convergence criteria etc.