{
  "id": 193898,
  "title": "Difference in missing data; Why?",
  "url": "/competitions/riiid-test-answer-prediction/discussion/193898",
  "author_name": "",
  "post_date": "2020-10-29T14:03:37.642674700Z",
  "votes": 3,
  "comment_count": 2,
  "views": 0,
  "content": "<p>The Data Description says:</p>\n<blockquote>\n  <p>Is null for a user's first question bundle or lecture</p>\n</blockquote>\n<p>for  <code>prior_question_elapsed_time</code> and <code>prior_question_had_explanation</code> columns.</p>\n<p>I calculated the missing percentage in both these columns:</p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F874280%2F1b883e3375e746959d8e8014eaec5d46%2FScreenshot%20from%202020-10-29%2019-18-25.png?generation=1603979335495930&amp;alt=media\" alt=\"\"></p>\n<p>Why do the missing ratios vary almost 6 times?</p>",
  "messages": [
    {
      "id": "1063925",
      "postDate": "10/29/2020 14:03:37",
      "content": "<p>The Data Description says:</p>\n<blockquote>\n  <p>Is null for a user's first question bundle or lecture</p>\n</blockquote>\n<p>for  <code>prior_question_elapsed_time</code> and <code>prior_question_had_explanation</code> columns.</p>\n<p>I calculated the missing percentage in both these columns:</p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F874280%2F1b883e3375e746959d8e8014eaec5d46%2FScreenshot%20from%202020-10-29%2019-18-25.png?generation=1603979335495930&amp;alt=media\" alt=\"\"></p>\n<p>Why do the missing ratios vary almost 6 times?</p>",
      "rawMarkdown": "The Data Description says:\n\n> Is null for a user's first question bundle or lecture\n\nfor  `prior_question_elapsed_time` and `prior_question_had_explanation` columns.\n\nI calculated the missing percentage in both these columns:\n\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F874280%2F1b883e3375e746959d8e8014eaec5d46%2FScreenshot%20from%202020-10-29%2019-18-25.png?generation=1603979335495930&alt=media)\n\nWhy do the missing ratios vary almost 6 times?",
      "votes": null
    },
    {
      "id": "1063968",
      "postDate": "10/29/2020 14:46:39",
      "content": "<p>The lecture rows are treated differently: prior_question_elapsed_time has <strong>NA</strong> while prior_question_had_explanation has <strong>0</strong>. Hence the difference.</p>\n<p>If you look at only the question rows they will match exactly.</p>",
      "rawMarkdown": "The lecture rows are treated differently: prior_question_elapsed_time has **NA** while prior_question_had_explanation has **0**. Hence the difference.\n\nIf you look at only the question rows they will match exactly.",
      "votes": null
    },
    {
      "id": "1064015",
      "postDate": "10/29/2020 15:52:42",
      "content": "<p>Thank you <a href=\"https://www.kaggle.com/rohanrao\" target=\"_blank\">@rohanrao</a>. The lecture rows are indeed distinct for both columns. </p>",
      "rawMarkdown": "Thank you @rohanrao. The lecture rows are indeed distinct for both columns.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 1063968,
      "author_name": "rohanrao",
      "author_url": "",
      "post_date": "10/29/2020 14:46:39",
      "content": "<p>The lecture rows are treated differently: prior_question_elapsed_time has <strong>NA</strong> while prior_question_had_explanation has <strong>0</strong>. Hence the difference.</p>\n<p>If you look at only the question rows they will match exactly.</p>",
      "votes": null,
      "replies": [
        {
          "id": 1064015,
          "author_name": "lplenka",
          "author_url": "",
          "post_date": "10/29/2020 15:52:42",
          "content": "<p>Thank you <a href=\"https://www.kaggle.com/rohanrao\" target=\"_blank\">@rohanrao</a>. The lecture rows are indeed distinct for both columns. </p>",
          "votes": null,
          "replies": []
        }
      ]
    }
  ],
  "raw_markdown_by_id": {
    "1063925": "The Data Description says:\n\n> Is null for a user's first question bundle or lecture\n\nfor  `prior_question_elapsed_time` and `prior_question_had_explanation` columns.\n\nI calculated the missing percentage in both these columns:\n\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F874280%2F1b883e3375e746959d8e8014eaec5d46%2FScreenshot%20from%202020-10-29%2019-18-25.png?generation=1603979335495930&alt=media)\n\nWhy do the missing ratios vary almost 6 times?",
    "1063968": "The lecture rows are treated differently: prior_question_elapsed_time has **NA** while prior_question_had_explanation has **0**. Hence the difference.\n\nIf you look at only the question rows they will match exactly.",
    "1064015": "Thank you @rohanrao. The lecture rows are indeed distinct for both columns."
  },
  "source": "meta"
}