Coefficient of Determination

Coefficient of Determination
-data = yi … yn
-predictions = fi..fn
-average of data = y

R^2 = 1 – Σn(yi-fi)/Σn(yi-y)^2

Calculating R^2

import numpy as np

def compute_r_squared(data, predictions):
	SST = ((data-np.mean(data))**2).sum()
	SSReg = ((predictions-data)**2).sum()
	r_squared = 1 - SSReg / SST

	return r_squared

Additional Considerations
– other types of linear regression
– ordinary least squares regression
– parameter estimation
– under / overfitting
– multiple local minima