Study on Coefficient of Correlation as Goodness-of-fit Criterion

In the experimental data disposal, correlation is often used as Criterion of linear fitting goodness. However, examples from some concrete experiment show that good linear fitting experiment data may not have larger correlation coefficient that Is to say, correlation coefficient is not suitable to be a criterion judging goodness of fitting. Only if it is also a regression one coefficient, orthere is one variable that can t be measured with a fixed scale, the correlation coefficient is of significant.