OI - Overall Index

\[\text{OI}(y, \hat{y}) = \frac{1}{2} \biggr[ 1 - \frac{RMSE}{y_{max} - y_{min}} + EC \biggr]\]

Latex equation code:

\text{OI}(y, \hat{y}) = \frac{1}{2} \biggr[ 1 - \frac{RMSE}{y_{max} - y_{min}} + EC \biggr]

The Overall Index (OI) [19] is a composite measure used to evaluate the accuracy of a forecasting model. It combines the Root Mean Squared Error (RMSE) with a measure of the relative error and a correction term. + Best possible value = 1, bigger value is better. Range = [-1, +1)

Example to use COR metric:

from numpy import array
from permetrics.regression import RegressionMetric

## For 1-D array
y_true = array([3, -0.5, 2, 7])
y_pred = array([2.5, 0.0, 2, 8])

evaluator = RegressionMetric(y_true, y_pred)
print(evaluator.overall_index())

## For > 1-D array
y_true = array([[0.5, 1], [-1, 1], [7, -6]])
y_pred = array([[0, 2], [-1, 2], [8, -5]])

evaluator = RegressionMetric(y_true, y_pred)
print(evaluator.OI(multi_output="raw_values"))