Table 3 Model performance evaluation indicators.

From: Hybrid-driven modeling using a BiLSTM–AdaBoost algorithm for diameter prediction in the constant diameter stage of Czochralski silicon single crystals

Norm

Define

Formulas

MSE

Mean square

\(MSE = \frac{1}{{\text{N}}}\mathop \sum \limits_{{{\text{i}} = 1}}^{{\text{N}}} ({\text{y}}({\text{i}}) - {\hat{\text{y}}}({\text{i}}))^{2}\)

RMSE

Root mean square

\(RMSE = \sqrt {\mathop \sum \limits_{{{\text{i}} = 1}}^{{\text{N}}} ({\text{y}}({\text{i}}) - {\hat{\text{y}}}({\text{i}}))^{2} }\)

MAE

Mean absolute value error

\(MAE = \frac{1}{{\text{N}}}\mathop \sum \limits_{{{\text{i}} = 1}}^{{\text{N}}} |{\text{y}}({\text{i}}) - {\hat{\text{y}}}({\text{i}})|\)

MAPE

Average absolute percentage error

\(MAE = \frac{1}{{\text{N}}}\mathop \sum \limits_{{{\text{i}} = 1}}^{{\text{N}}} \left| {\frac{{{\text{y}}({\text{i}}) - {\hat{\text{y}}}({\text{i}})}}{{{\text{y}}({\text{i}})}}} \right| \times 100{\text{\% }}\)

R2

Coefficient of determination

\(R^{2} = 1 - \frac{{\mathop \sum \limits_{i = 1}^{N} ({\text{y}}({\text{i}}) - {\hat{\text{y}}}({\text{i}}))^{2} }}{{\mathop \sum \limits_{i = 1}^{N} ({\text{y}}({\text{i}}) - \overline{{\text{y}}} ({\text{i}}))^{2} }}\)