目标检测评价指标mAP 精准率和召回率

• 2019 年 10 月 3 日
• 筆記

????????,???,???,???

• ???precision
• ???recall
• ???accuracy

?????????,?????100?????. 95???????,5???????. ?????????,??????????????.
??,????????,?100???,5????,95????.?????1,1,1,1,1,0,0,…….(??5?????,?95????).
???????????1,0,0,1,1,1,0…….,?????????????????????,?6?????????.
???????100???,??3?,??97?.????4???,??3???,1???.

????????,???accuracy.?????????=97/100=97%.

?????precision,??????????????,??????4??????,????,???=3/4=75%.

?????recall,?????????(?5?)??,?????5???,??????,???=3/5=60%.

???????????,precision?????????????(?????????,???????.??????????,???????????,???????????????,?????????????????)?,???????????,???????precision.

recall??????,?????????,????????recall.

??????:
precision?????????,???????.
recall????????,???????.

???precision????recall??,?????????????.??:

1. ??????
   ????????????????,???????????????????,???????????????!,??????????????????????,???????. ??????????,????????,????,????????. ?????,precision??????.

2. ????
   ????????????????????,??,???????,????????,??????????,???????. ???????????????,????,?????????????????????????. ?????,recall???????.

?????2????????,???,?????????precision?recall???????????.

mAP

???AP (Average Precision)
???????,???AP???.?????1000???,??5????,????????????????.?????????????????,?????????.

????????????????????.

??????,????,??????????,??????2?,???3?,?????????5?,??precision=2/3=0.67, recall=2/5=0.4.

????,?????????:

??????"?"?????.????,????,recall????????.precision??"??".

AP?????recall-precision????.

???????,?????????recall????precision????????.

?

PASCAL Visual Objects Challenge?2007???????????????????????????Precision-recall ??????.

AP???:AP?????recall?precision???,???????????????.
mAP??????AP???????????????????????