def _calculate_variance_reduction(self, y, y1, y2):
var_tot = calculate_variance(y)
var_1 = calculate_variance(y1)
var_2 = calculate_variance(y2)
frac_1 = len(y1) / len(y)
frac_2 = len(y2) / len(y)
# Calculate the variance reduction
variance_reduction = var_tot - (frac_1 * var_1 + frac_2 * var_2)
return sum(variance_reduction)
def _calculate_variance_reduction(self, y, y1, y2):
var_tot = calculate_variance(y)
var_1 = calculate_variance(y1)
var_2 = calculate_variance(y2)
frac_1 = len(y1) / len(y)
frac_2 = len(y2) / len(y)
# Calculate the variance reduction
variance_reduction = var_tot - (frac_1 * var_1 + frac_2 * var_2)
return sum(variance_reduction)