Table 6 Performance Measuring Parameters.

From: Advanced air quality prediction using multimodal data and dynamic modeling techniques

Metric

Formula

Description

Mean Squared Error (MSE)

\(\text{MSE}=\frac{1}{\text{n}}\sum_{\text{i}=1}^{\text{n}}{({\text{y}}_{\text{i}}-\widehat{{\text{y}}_{\text{i}}})}^{2}\) (25)

Measures the average squared difference between predicted and actual values

Mean Absolute Error (MAE)

\(\text{MAE}=\frac{1}{\text{n}}\sum_{\text{i}=1}^{\text{n}}{(|{\text{y}}_{\text{i}}-\widehat{{\text{y}}_{\text{i}}}|)}\) (26)

Measures the average absolute difference between predicted and actual values

Root Mean Squared Error (RMSE)

\(\text{RMSE}=\sqrt[ ]{\frac{1}{\text{n}}\sum_{\text{i}=1}^{\text{n}}{({\text{y}}_{\text{i}}-\widehat{{\text{y}}_{\text{i}}})}^{2}}\) (27)

The square root of MSE gives error in the same units as the target variable

R-squared (R2)

\({\text{R}}^{2}=[1-\frac{\frac{1}{\text{n}}\sum_{\text{i}=1}^{\text{n}}{({\text{y}}_{\text{i}}-\widehat{{\text{y}}_{\text{i}}})}^{2} }{\frac{1}{\text{n}}\sum_{\text{i}=1}^{\text{n}}{({\text{y}}_{\text{i}}-\widehat{{\text{y}}_{ }})}^{2} }]\) (28)

Indicates how well the model explains the variance in the target variable

Explained Variance Score (EVS)

\(\text{EVS}=[1-\frac{\text{Var }{({\text{y}}_{\text{i}}-\widehat{{\text{y}}_{\text{i}}})}^{2} }{\text{Var}(\text{y}) }]\) (29)

Measures how much of the variance in the data is explained by the model

Mean Absolute Percentage Error (MAPE)

\(\text{MAPE}=\frac{1}{\text{n}}\sum_{\text{i}=1}^{\text{n}}{(|\frac{{\text{y}}_{\text{i}}-\widehat{{\text{y}}_{\text{i}}}}{{\text{y}}_{\text{i}}}|)}\) (30)

Measures prediction accuracy as a percentage

Precision (P)

\(\text{P}=\frac{\text{TP}}{(\text{TP}+\text{FP})}\) (31)

Fraction of relevant instances retrieved

Recall (RC)

\(\text{RC}=\frac{\text{TP}}{(\text{TP}+\text{FN})}\) (32)

Fraction of relevant instances that were retrieved

F1-Score (FS)

\(FS=2\times \frac{P\times RC}{(P+RC)}\) (33)

The harmonic mean of precision and recall balances both metrics

Area Under the Curve—Receiver Operating Characteristic AUC-ROC

AUC-ROC is computed as the area under the ROC curve (TPR vs. FPR)

Measures the model’s ability to distinguish between classes

  1. Where \({y}_{i}\): Actual Value, \(\widehat{{y}_{i}}\): Predicted Value, n: number of data points, TP: True positive, FP: False Positive, FN: False Negative, FP: False Positive.