{
  "id": 126616,
  "title": "Maybe hashed features are correlated.",
  "url": "/competitions/cat-in-the-dat-ii/discussion/126616",
  "author_name": "",
  "post_date": "2020-01-18T20:41:38.124649200Z",
  "votes": 6,
  "comment_count": 7,
  "views": 0,
  "content": "<p>So, I have implemented correlation functions from <a href=\"https://towardsdatascience.com/the-search-for-categorical-correlation-a1cf7f1888c9\">this</a> article. You can find it in <a href=\"https://www.kaggle.com/vadbeg/pytorch-nn-with-embeddings-and-catboost\">my kernel</a>. So, thats what I have founded:\n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fc2f284c8e30befd559890bf27ea9ba16%2F__results___43_2.png?generation=1579379228688910&amp;alt=media\" alt=\"\"></p>\n\n<p>So, as you can see features nom_{5-9} are, somehow,  connected. I used Theil's U statistic to find it. Maybe I've got an error. Or they are correlated because of huge amount of unique elements in nom_9 or nom_6. Can somebody explain it to me?</p>",
  "messages": [
    {
      "id": "722627",
      "postDate": "01/18/2020 20:41:38",
      "content": "<p>So, I have implemented correlation functions from <a href=\"https://towardsdatascience.com/the-search-for-categorical-correlation-a1cf7f1888c9\">this</a> article. You can find it in <a href=\"https://www.kaggle.com/vadbeg/pytorch-nn-with-embeddings-and-catboost\">my kernel</a>. So, thats what I have founded:\n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fc2f284c8e30befd559890bf27ea9ba16%2F__results___43_2.png?generation=1579379228688910&amp;alt=media\" alt=\"\"></p>\n\n<p>So, as you can see features nom_{5-9} are, somehow,  connected. I used Theil's U statistic to find it. Maybe I've got an error. Or they are correlated because of huge amount of unique elements in nom_9 or nom_6. Can somebody explain it to me?</p>",
      "rawMarkdown": "So, I have implemented correlation functions from [this](https://towardsdatascience.com/the-search-for-categorical-correlation-a1cf7f1888c9) article. You can find it in [my kernel](https://www.kaggle.com/vadbeg/pytorch-nn-with-embeddings-and-catboost). So, thats what I have founded:\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fc2f284c8e30befd559890bf27ea9ba16%2F__results___43_2.png?generation=1579379228688910&amp;alt=media)\n\nSo, as you can see features nom\\_{5-9} are, somehow,  connected. I used Theil's U statistic to find it. Maybe I've got an error. Or they are correlated because of huge amount of unique elements in nom\\_9 or nom\\_6. Can somebody explain it to me?",
      "votes": null
    },
    {
      "id": "723579",
      "postDate": "01/20/2020 07:20:16",
      "content": "<p>hmm so the feature counts are correlated for those variables... yeah it could be because they are all close to 1, right?</p>",
      "rawMarkdown": "hmm so the feature counts are correlated for those variables... yeah it could be because they are all close to 1, right?",
      "votes": null
    },
    {
      "id": "723592",
      "postDate": "01/20/2020 07:43:14",
      "content": "<p>What did you mean under feature counts? Features nom_{5-9} consists of hundreds and thousands of unique values. We can use OneHotEncoding for them, and they will be 0 or 1. But I have used LabelEncoding, so hashed features are just numbers. Explain it, please. </p>",
      "rawMarkdown": "What did you mean under feature counts? Features nom_{5-9} consists of hundreds and thousands of unique values. We can use OneHotEncoding for them, and they will be 0 or 1. But I have used LabelEncoding, so hashed features are just numbers. Explain it, please.",
      "votes": null
    },
    {
      "id": "723713",
      "postDate": "01/20/2020 11:06:19",
      "content": "<p>I'm not sure what to do if the nominal values are actually numbers.</p>\n\n<p>Maybe a brute force method to test effectiveness of different label encodings?</p>",
      "rawMarkdown": "I'm not sure what to do if the nominal values are actually numbers.\n\nMaybe a brute force method to test effectiveness of different label encodings?",
      "votes": null
    },
    {
      "id": "729780",
      "postDate": "01/26/2020 16:24:55",
      "content": "<p>Pretty interesting <a href=\"/vadbeg\">@vadbeg</a>, this high correlation found are in respect with the same unique element in both columns?</p>",
      "rawMarkdown": "Pretty interesting @vadbeg, this high correlation found are in respect with the same unique element in both columns?",
      "votes": null
    },
    {
      "id": "729813",
      "postDate": "01/26/2020 17:04:04",
      "content": "<p>No, as I remember, in this columns there is no same elements. \n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fd93705a3ab33dcfc89a2dd63adb9de5f%2F1_3Mx7I537OnQybSOMPvgqEw.png?generation=1580058005120051&amp;alt=media\" alt=\"\"></p>\n\n<p>This correlation explains how we can determine elements from one column using elements from another one (in this table we can determine every element from <i>X</i> using elements from <i>Y</i>, but not vice versa)</p>",
      "rawMarkdown": "No, as I remember, in this columns there is no same elements. \n![](https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fd93705a3ab33dcfc89a2dd63adb9de5f%2F1_3Mx7I537OnQybSOMPvgqEw.png?generation=1580058005120051&amp;alt=media)\n\nThis correlation explains how we can determine elements from one column using elements from another one (in this table we can determine every element from <i>X</i> using elements from <i>Y</i>, but not vice versa)",
      "votes": null
    },
    {
      "id": "730318",
      "postDate": "01/27/2020 10:46:10",
      "content": "<p>Interesting, maybe there's a bottom to top correlation that must happen.</p>",
      "rawMarkdown": "Interesting, maybe there's a bottom to top correlation that must happen.",
      "votes": null
    },
    {
      "id": "739177",
      "postDate": "02/07/2020 14:12:36",
      "content": "<p>I tried to use them as numbers, I did not get a very good result. In fact I tried different pre-processing strategies and tested them with and without using numbers for <code>nom_5</code> to <code>nom_9.</code> I always got a worse result when using numbers. I normalized them before of course.  Well, in the competition, they say these features are strings, so I suppose we are to use them as such, and not as numbers. </p>",
      "rawMarkdown": "I tried to use them as numbers, I did not get a very good result. In fact I tried different pre-processing strategies and tested them with and without using numbers for `nom_5` to `nom_9.` I always got a worse result when using numbers. I normalized them before of course.  Well, in the competition, they say these features are strings, so I suppose we are to use them as such, and not as numbers.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 723579,
      "author_name": "rkotwani",
      "author_url": "",
      "post_date": "01/20/2020 07:20:16",
      "content": "<p>hmm so the feature counts are correlated for those variables... yeah it could be because they are all close to 1, right?</p>",
      "votes": null,
      "replies": [
        {
          "id": 723592,
          "author_name": "vadbeg",
          "author_url": "",
          "post_date": "01/20/2020 07:43:14",
          "content": "<p>What did you mean under feature counts? Features nom_{5-9} consists of hundreds and thousands of unique values. We can use OneHotEncoding for them, and they will be 0 or 1. But I have used LabelEncoding, so hashed features are just numbers. Explain it, please. </p>",
          "votes": null,
          "replies": []
        },
        {
          "id": 723713,
          "author_name": "rkotwani",
          "author_url": "",
          "post_date": "01/20/2020 11:06:19",
          "content": "<p>I'm not sure what to do if the nominal values are actually numbers.</p>\n\n<p>Maybe a brute force method to test effectiveness of different label encodings?</p>",
          "votes": null,
          "replies": []
        }
      ]
    },
    {
      "id": 729780,
      "author_name": "brunhs",
      "author_url": "",
      "post_date": "01/26/2020 16:24:55",
      "content": "<p>Pretty interesting <a href=\"/vadbeg\">@vadbeg</a>, this high correlation found are in respect with the same unique element in both columns?</p>",
      "votes": null,
      "replies": [
        {
          "id": 729813,
          "author_name": "vadbeg",
          "author_url": "",
          "post_date": "01/26/2020 17:04:04",
          "content": "<p>No, as I remember, in this columns there is no same elements. \n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fd93705a3ab33dcfc89a2dd63adb9de5f%2F1_3Mx7I537OnQybSOMPvgqEw.png?generation=1580058005120051&amp;alt=media\" alt=\"\"></p>\n\n<p>This correlation explains how we can determine elements from one column using elements from another one (in this table we can determine every element from <i>X</i> using elements from <i>Y</i>, but not vice versa)</p>",
          "votes": null,
          "replies": []
        },
        {
          "id": 730318,
          "author_name": "brunhs",
          "author_url": "",
          "post_date": "01/27/2020 10:46:10",
          "content": "<p>Interesting, maybe there's a bottom to top correlation that must happen.</p>",
          "votes": null,
          "replies": []
        }
      ]
    },
    {
      "id": 739177,
      "author_name": "catadanna",
      "author_url": "",
      "post_date": "02/07/2020 14:12:36",
      "content": "<p>I tried to use them as numbers, I did not get a very good result. In fact I tried different pre-processing strategies and tested them with and without using numbers for <code>nom_5</code> to <code>nom_9.</code> I always got a worse result when using numbers. I normalized them before of course.  Well, in the competition, they say these features are strings, so I suppose we are to use them as such, and not as numbers. </p>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "722627": "So, I have implemented correlation functions from [this](https://towardsdatascience.com/the-search-for-categorical-correlation-a1cf7f1888c9) article. You can find it in [my kernel](https://www.kaggle.com/vadbeg/pytorch-nn-with-embeddings-and-catboost). So, thats what I have founded:\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fc2f284c8e30befd559890bf27ea9ba16%2F__results___43_2.png?generation=1579379228688910&amp;alt=media)\n\nSo, as you can see features nom\\_{5-9} are, somehow,  connected. I used Theil's U statistic to find it. Maybe I've got an error. Or they are correlated because of huge amount of unique elements in nom\\_9 or nom\\_6. Can somebody explain it to me?",
    "723579": "hmm so the feature counts are correlated for those variables... yeah it could be because they are all close to 1, right?",
    "723592": "What did you mean under feature counts? Features nom_{5-9} consists of hundreds and thousands of unique values. We can use OneHotEncoding for them, and they will be 0 or 1. But I have used LabelEncoding, so hashed features are just numbers. Explain it, please.",
    "723713": "I'm not sure what to do if the nominal values are actually numbers.\n\nMaybe a brute force method to test effectiveness of different label encodings?",
    "729780": "Pretty interesting @vadbeg, this high correlation found are in respect with the same unique element in both columns?",
    "729813": "No, as I remember, in this columns there is no same elements. \n![](https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F2594941%2Fd93705a3ab33dcfc89a2dd63adb9de5f%2F1_3Mx7I537OnQybSOMPvgqEw.png?generation=1580058005120051&amp;alt=media)\n\nThis correlation explains how we can determine elements from one column using elements from another one (in this table we can determine every element from <i>X</i> using elements from <i>Y</i>, but not vice versa)",
    "730318": "Interesting, maybe there's a bottom to top correlation that must happen.",
    "739177": "I tried to use them as numbers, I did not get a very good result. In fact I tried different pre-processing strategies and tested them with and without using numbers for `nom_5` to `nom_9.` I always got a worse result when using numbers. I normalized them before of course.  Well, in the competition, they say these features are strings, so I suppose we are to use them as such, and not as numbers."
  },
  "source": "meta"
}