{
  "id": 3617,
  "title": "Every user in \"train.csv\" is not in \"test.csv\"!",
  "url": "/competitions/event-recommendation-engine-challenge/discussion/3617",
  "author_name": "",
  "post_date": "2013-01-17T11:30:50.413Z",
  "votes": null,
  "comment_count": 2,
  "views": 1400,
  "content": "<p>Every user in &quot;train.csv&quot; is not in &quot;test.csv&quot;!</p>\r\n<p>why is that?</p>",
  "messages": [
    {
      "id": "19392",
      "postDate": "01/17/2013 11:30:50",
      "content": "<p>Every user in &quot;train.csv&quot; is not in &quot;test.csv&quot;!</p>\r\n<p>why is that?</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "19393",
      "postDate": "01/17/2013 12:59:07",
      "content": "<p>Some % of Total user data = test data &#43; train data </p>\r\n<p>Is that true ?</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "19447",
      "postDate": "01/18/2013 13:04:21",
      "content": "<p>I agree, this surprised me when I realized it -- I was starting to wonder why collaborative filtering had no real effect. This is an unusual setup in general for a recommender problem. It's not unusual to have to serve good results to users who are brand-new,\r\n but these users seem to have signficant activity history that is not given. I'd think you would want to be able to use this.</p>",
      "rawMarkdown": "",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 19393,
      "author_name": "ydhiman",
      "author_url": "",
      "post_date": "01/17/2013 12:59:07",
      "content": "<p>Some % of Total user data = test data &#43; train data </p>\r\n<p>Is that true ?</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 19447,
      "author_name": "",
      "author_url": "",
      "post_date": "01/18/2013 13:04:21",
      "content": "<p>I agree, this surprised me when I realized it -- I was starting to wonder why collaborative filtering had no real effect. This is an unusual setup in general for a recommender problem. It's not unusual to have to serve good results to users who are brand-new,\r\n but these users seem to have signficant activity history that is not given. I'd think you would want to be able to use this.</p>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "19392": "",
    "19393": "",
    "19447": ""
  },
  "source": "meta"
}