{
  "id": 301271,
  "title": "Question about the metric",
  "url": "/competitions/tensorflow-great-barrier-reef/discussion/301271",
  "author_name": "",
  "post_date": "2022-01-16T19:16:24.276434Z",
  "votes": 5,
  "comment_count": 2,
  "views": 0,
  "content": "<p><img src=\"https://i.imgur.com/Vu38KlB.jpg\" alt=\"\"></p>\n<p>Assume that pred box1 and pred box2 can match true box1, true box2 can be matched by pred box2 too.<br>\nIf pred box1 match with true box1, pred box2 match with true box2 --&gt; tp = 2, fp = 0, fn = 0<br>\nif pred box2 match with true box1, pred box1 cannot match with true box2 --&gt; tp = 1, fp = 1, fn = 1</p>\n<p>which case is right for this competition's metric? </p>",
  "messages": [
    {
      "id": "1652596",
      "postDate": "01/16/2022 19:16:24",
      "content": "<p><img src=\"https://i.imgur.com/Vu38KlB.jpg\" alt=\"\"></p>\n<p>Assume that pred box1 and pred box2 can match true box1, true box2 can be matched by pred box2 too.<br>\nIf pred box1 match with true box1, pred box2 match with true box2 --&gt; tp = 2, fp = 0, fn = 0<br>\nif pred box2 match with true box1, pred box1 cannot match with true box2 --&gt; tp = 1, fp = 1, fn = 1</p>\n<p>which case is right for this competition's metric? </p>",
      "rawMarkdown": "![](https://i.imgur.com/Vu38KlB.jpg)\n\nAssume that pred box1 and pred box2 can match true box1, true box2 can be matched by pred box2 too.\nIf pred box1 match with true box1, pred box2 match with true box2 --> tp = 2, fp = 0, fn = 0\nif pred box2 match with true box1, pred box1 cannot match with true box2 --> tp = 1, fp = 1, fn = 1\n\nwhich case is right for this competition's metric?",
      "votes": null
    },
    {
      "id": "1652636",
      "postDate": "01/16/2022 20:13:08",
      "content": "<p>Depends on NMS setting, first you keep best conf score, then count IOU, but it is not need in your thinking process becuase it is tear in the sea. You probably wont be albe to get benefit of it :) just use NMS and go sleep :)</p>\n<p>-- however if pred 1 belongs to gt 1 and pred 2 belongs to gt2, you will score only for iou 0.3..0.4 and for 0.4 to 0.8 it will be counted as false positive and false negative so even if you predicted starfish but with weak accuracy of bboxes it will couint only for low iou ;) for rest it will count negative!</p>",
      "rawMarkdown": "Depends on NMS setting, first you keep best conf score, then count IOU, but it is not need in your thinking process becuase it is tear in the sea. You probably wont be albe to get benefit of it :) just use NMS and go sleep :)\n\n-- however if pred 1 belongs to gt 1 and pred 2 belongs to gt2, you will score only for iou 0.3..0.4 and for 0.4 to 0.8 it will be counted as false positive and false negative so even if you predicted starfish but with weak accuracy of bboxes it will couint only for low iou ;) for rest it will count negative!",
      "votes": null
    },
    {
      "id": "1661003",
      "postDate": "01/23/2022 06:30:03",
      "content": "<p>So does it mean that we should set a higher bbox_ iou and a lower conf ?</p>",
      "rawMarkdown": "So does it mean that we should set a higher bbox_ iou and a lower conf ?",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 1652636,
      "author_name": "lukaszborecki",
      "author_url": "",
      "post_date": "01/16/2022 20:13:08",
      "content": "<p>Depends on NMS setting, first you keep best conf score, then count IOU, but it is not need in your thinking process becuase it is tear in the sea. You probably wont be albe to get benefit of it :) just use NMS and go sleep :)</p>\n<p>-- however if pred 1 belongs to gt 1 and pred 2 belongs to gt2, you will score only for iou 0.3..0.4 and for 0.4 to 0.8 it will be counted as false positive and false negative so even if you predicted starfish but with weak accuracy of bboxes it will couint only for low iou ;) for rest it will count negative!</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 1661003,
      "author_name": "elonzhou",
      "author_url": "",
      "post_date": "01/23/2022 06:30:03",
      "content": "<p>So does it mean that we should set a higher bbox_ iou and a lower conf ?</p>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "1652596": "![](https://i.imgur.com/Vu38KlB.jpg)\n\nAssume that pred box1 and pred box2 can match true box1, true box2 can be matched by pred box2 too.\nIf pred box1 match with true box1, pred box2 match with true box2 --> tp = 2, fp = 0, fn = 0\nif pred box2 match with true box1, pred box1 cannot match with true box2 --> tp = 1, fp = 1, fn = 1\n\nwhich case is right for this competition's metric?",
    "1652636": "Depends on NMS setting, first you keep best conf score, then count IOU, but it is not need in your thinking process becuase it is tear in the sea. You probably wont be albe to get benefit of it :) just use NMS and go sleep :)\n\n-- however if pred 1 belongs to gt 1 and pred 2 belongs to gt2, you will score only for iou 0.3..0.4 and for 0.4 to 0.8 it will be counted as false positive and false negative so even if you predicted starfish but with weak accuracy of bboxes it will couint only for low iou ;) for rest it will count negative!",
    "1661003": "So does it mean that we should set a higher bbox_ iou and a lower conf ?"
  },
  "source": "meta"
}