What should I believe in nonlinear curve fitting, Chi-square or R-square?

correlation - Can the Chi-Square Value be Used to Quantitatively Discuss Goodness of Fit for any Data? - Cross Validated

Nonlinear Least-Squares Fitting — GSL 2.7 documentation

Curve fitting using PSO?

Overfitting- corrected calibration curve of Poisson regression

Why does zinc chloride salt powder melt at 50 degrees?

generalized linear model - What is a partial chi-square statistic according to Frank Harrell? - Cross Validated

Meaning of a non reversible endothermic peak in DSC, any idea

GraphPad Prism 10 Curve Fitting Guide - R squared

Curve Fitting in R - GeeksforGeeks

Accuracy of ChatGPT on Statistical Methods - research methods - Datamethods Discussion Forum

What is the best way to undertake a multiple linear regression