Coefficient of determination

Selects the method to be used to calculate the Coefficient of determination, which is also known as R² value. The following options are available from the drop-down list:

• Default method: Uses the intercept-free model in assays based on linear regression models, and the mean-adjusted model in assays based on nonlinear regression models.
  Note: Assays based on the restricted regression model of the Slope ratio are an exception where also the mean-adjusted model is used by default.
• Mean-adjusted model: Calculates the Coefficient of determination based on the following equation:
  $$R^2=1-\genfrac{}{}{0.1ex}{}{{\displaystyle \sum _i}{({\widehat{y}}_i-y_i)}^2}{{\displaystyle \sum _i}{(y_i-\overline{y})}^2}$$

  Where ȳ is the average response, y_i is the i-th response and ŷ_i is the i-th reponse predicted by the fitted model.

• Intercept-free model: Calculates the Coefficient of determination based on the following equation:
  $$R^2=1-\genfrac{}{}{0.1ex}{}{{\displaystyle \sum _i}{({\widehat{y}}_i-y_i)}^2}{{\displaystyle \sum _i}{y}_i^2}$$

  Where y_i is the i-th response and ŷ_i is the i-th reponse predicted by the fitted model.

This element has the following attributes:

Context:

/Quantitative response assay/Analysis/Analytical model/Advanced settings/