{
  "id": 304250,
  "title": "Weird CV and LB",
  "url": "/competitions/tensorflow-great-barrier-reef/discussion/304250",
  "author_name": "",
  "post_date": "2022-01-31T11:13:06.073564Z",
  "votes": null,
  "comment_count": 3,
  "views": 0,
  "content": "<p>I am using subsequences <a href=\"url\" target=\"_blank\">https://www.kaggle.com/julian3833/reef-a-cv-strategy-subsequences</a> to divide the dataset. Use <a href=\"url\" target=\"_blank\">https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302241</a> for F2 score statistics.<br>\nI used the weight of Big Brother Sheep <a href=\"url\" target=\"_blank\">https://www.kaggle.com/steamedsheep/yolov5-is-all-you-need</a> in local cv0.503, using stacking <a href=\"url\" target=\"_blank\"></a><a href=\"https://www.kaggle.com/naturezhang/yolov5\" target=\"_blank\">https://www.kaggle.com/naturezhang/yolov5</a> -detections-tracking-on-cot has LB of 0.643. But the model I trained has 0.523 in local CV, but in C the LB is only 0.556.<br>\nSlowly the local CV is greater than 0.503 but why is the LB so different.<br>\nThis is very strange Can someone tell me why?</p>",
  "messages": [
    {
      "id": "1670262",
      "postDate": "01/31/2022 11:13:06",
      "content": "<p>I am using subsequences <a href=\"url\" target=\"_blank\">https://www.kaggle.com/julian3833/reef-a-cv-strategy-subsequences</a> to divide the dataset. Use <a href=\"url\" target=\"_blank\">https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302241</a> for F2 score statistics.<br>\nI used the weight of Big Brother Sheep <a href=\"url\" target=\"_blank\">https://www.kaggle.com/steamedsheep/yolov5-is-all-you-need</a> in local cv0.503, using stacking <a href=\"url\" target=\"_blank\"></a><a href=\"https://www.kaggle.com/naturezhang/yolov5\" target=\"_blank\">https://www.kaggle.com/naturezhang/yolov5</a> -detections-tracking-on-cot has LB of 0.643. But the model I trained has 0.523 in local CV, but in C the LB is only 0.556.<br>\nSlowly the local CV is greater than 0.503 but why is the LB so different.<br>\nThis is very strange Can someone tell me why?</p>",
      "rawMarkdown": "I am using subsequences [https://www.kaggle.com/julian3833/reef-a-cv-strategy-subsequences](url) to divide the dataset. Use [https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302241](url) for F2 score statistics.\nI used the weight of Big Brother Sheep [https://www.kaggle.com/steamedsheep/yolov5-is-all-you-need](url) in local cv0.503, using stacking [https://www.kaggle.com/naturezhang/yolov5 -detections-tracking-on-cot](url) has LB of 0.643. But the model I trained has 0.523 in local CV, but in C the LB is only 0.556.\nSlowly the local CV is greater than 0.503 but why is the LB so different.\nThis is very strange Can someone tell me why?",
      "votes": null
    },
    {
      "id": "1670339",
      "postDate": "01/31/2022 12:44:07",
      "content": "<p>helphelphelp</p>",
      "rawMarkdown": "helphelphelp",
      "votes": null
    },
    {
      "id": "1670750",
      "postDate": "01/31/2022 20:44:38",
      "content": "<p>Check out this discussion here:<br>\n<a href=\"https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302057\" target=\"_blank\">https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302057</a></p>\n<p>It talks about how there is probably some training images in the LB. So while your CV is seeing new data the LB might be seeing new data + training data. It's worth thinking about.</p>",
      "rawMarkdown": "Check out this discussion here:\nhttps://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302057\n\nIt talks about how there is probably some training images in the LB. So while your CV is seeing new data the LB might be seeing new data + training data. It's worth thinking about.",
      "votes": null
    },
    {
      "id": "1671040",
      "postDate": "02/01/2022 05:32:41",
      "content": "<p>Thank you for your answer</p>",
      "rawMarkdown": "Thank you for your answer",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 1670339,
      "author_name": "henini",
      "author_url": "",
      "post_date": "01/31/2022 12:44:07",
      "content": "<p>helphelphelp</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 1670750,
      "author_name": "ivanaerlic",
      "author_url": "",
      "post_date": "01/31/2022 20:44:38",
      "content": "<p>Check out this discussion here:<br>\n<a href=\"https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302057\" target=\"_blank\">https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302057</a></p>\n<p>It talks about how there is probably some training images in the LB. So while your CV is seeing new data the LB might be seeing new data + training data. It's worth thinking about.</p>",
      "votes": null,
      "replies": [
        {
          "id": 1671040,
          "author_name": "henini",
          "author_url": "",
          "post_date": "02/01/2022 05:32:41",
          "content": "<p>Thank you for your answer</p>",
          "votes": null,
          "replies": []
        }
      ]
    }
  ],
  "raw_markdown_by_id": {
    "1670262": "I am using subsequences [https://www.kaggle.com/julian3833/reef-a-cv-strategy-subsequences](url) to divide the dataset. Use [https://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302241](url) for F2 score statistics.\nI used the weight of Big Brother Sheep [https://www.kaggle.com/steamedsheep/yolov5-is-all-you-need](url) in local cv0.503, using stacking [https://www.kaggle.com/naturezhang/yolov5 -detections-tracking-on-cot](url) has LB of 0.643. But the model I trained has 0.523 in local CV, but in C the LB is only 0.556.\nSlowly the local CV is greater than 0.503 but why is the LB so different.\nThis is very strange Can someone tell me why?",
    "1670339": "helphelphelp",
    "1670750": "Check out this discussion here:\nhttps://www.kaggle.com/c/tensorflow-great-barrier-reef/discussion/302057\n\nIt talks about how there is probably some training images in the LB. So while your CV is seeing new data the LB might be seeing new data + training data. It's worth thinking about.",
    "1671040": "Thank you for your answer"
  },
  "source": "meta"
}