序列标注任务效果指标计算方法

true	PER	PER	PER	O	O	O	LOC	O	ORG	ORG
predict	PER	PER	O	O	O	O	LOC	LOC	O	ORG
num_correct(预测正确，true label中不包含"O")	1	1	0	-	-	-	1	0	0	1
num_proposed(predict label中不包含"O")	1	1	-	-	-	-	1	1	-	1
num_gold(true label中不包含"O")	1	1	1	-	-	-	1	-	1	1

num_correct = (np.logical_and(true_labels == pred_labels, true_labels != 'O')).astype(np.int).sum()
num_correct = (np.logical_and(true_labels == pred_labels, true_labels != 'O')).astype(np.int).sum()  # 预测标签=实际标签，并且除去O
num_gold = len(true_labels[true_labels != 'O'])  # 实际标签中去除O的

precision = num_correct / num_proposed
recall = num_correct / num_gold
f1 = 2 * precision * recall / (precision + recall)