{
  "id": 5790,
  "title": "Has anyone managed to achieve a high leaderboard score using legitimate features only?",
  "url": "/competitions/accelerometer-biometric-competition/discussion/5790",
  "author_name": "",
  "post_date": "2013-09-17T16:32:12.067Z",
  "votes": 1,
  "comment_count": 11,
  "views": 5239,
  "content": "<p><br>You are invited to make submissions that do not exploit the existing leakage. (See thread &#8220;Preparing fresh data without leakage &#8211; Request for comments&#8221;)</p>\n<p><br>The organizers will compensate (out of band to this competition) contestants that can demonstrate high leaderboard scores using legitimate features only. </p>\n<p>&nbsp;</p>",
  "messages": [
    {
      "id": "31053",
      "postDate": "09/17/2013 16:32:12",
      "content": "<p><br>You are invited to make submissions that do not exploit the existing leakage. (See thread &#8220;Preparing fresh data without leakage &#8211; Request for comments&#8221;)</p>\n<p><br>The organizers will compensate (out of band to this competition) contestants that can demonstrate high leaderboard scores using legitimate features only. </p>\n<p>&nbsp;</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31064",
      "postDate": "09/17/2013 21:50:52",
      "content": "<p>Hi Geoff</p>\n<p>I like your idea, and am looking forward to read more about how you want to implement it concretely.</p>\n<p>What demonstration do you have in mind? In general, you might need to take a look at model code and algorithm description in order to decide whether it fits your criteria. This is done by other Kaggle competitions, but I guess it takes time and effort.</p>\n<p>&nbsp;</p>\n<p>Personally, I think that my solution fits the legitimate criteria - without revealing too much I can say I use a classical supervised learning paradigm - construct features of the train set 4D signals, train a ML method, predict on the test data. Would this be legitimate for your criteria and constitute a solution useful for the competition organizers?</p>\n<p>Sometimes it is tricky to decide for some technical implementation details - e.g. usually using the training set distribution in a clever way belongs to good data science practice, but in this competition one of the problems is supposed to be the same distribution of train and test set.</p>\n<p>However, I have a feeling this is one of the smallest leaks, less serious than the time stamp issues and other mysterious leaks to which the top players hint at :-)</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31082",
      "postDate": "09/18/2013 13:39:31",
      "content": "<p>Hi Dieselboy,</p>\n<p>Thanks for responding to this invitation. I'm pleased to see a high scoring submission that didn't attempt to exploit the leakage. We would want to review your code &amp; maybe talk to ascertain that results are not impacted by leakage. If we can determine that score above 90% &nbsp;is attributable to legitimate features only, you will be rewarded. Please contact me directly to geoffkle@gmail.com, to discuss progressing this further.</p>\n<p>&nbsp;</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31364",
      "postDate": "09/23/2013 00:50:30",
      "content": "<p>Newbie here. Would love to understand what qualifies as a high score ? Are AUCs &gt; .9 achievable using only legitimate features ?</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31375",
      "postDate": "09/23/2013 05:48:23",
      "content": "<p>AUC &gt; 0.9</p>\n<p>This is what we would like to find out :)</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31504",
      "postDate": "09/24/2013 16:19:31",
      "content": "<p>I use the same approach as&nbsp;Dieselboy, I think it is not too difficult to get score &gt;0.9 without using any leakages. I think moreover it is possible to get AUC&gt;0.9 even without time feature.</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31570",
      "postDate": "09/25/2013 21:33:26",
      "content": "<p>Hi diaman, would love to review your model, please contact me by email.</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31704",
      "postDate": "09/28/2013 12:20:50",
      "content": "<p>[quote=Geoff;31082]</p>\n<p><span style=\"line-height: 1.4\">If we can determine that score above 90% &nbsp;is attributable to legitimate features only, you will be rewarded.&nbsp;</span>[/quote]</p>\n<p>&nbsp;</p>\n<p>Hi ! I just run my models without leakage and I got 0.90924 on leaderboard score. I used T the same way as the other variables, the only difference is that, instead using T I used diff(T).</p>\n<p>I wonder what kind of reward could we expect if we share you our leakage free models scoring more than 0.90 ?</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31711",
      "postDate": "09/28/2013 13:46:54",
      "content": "<p>Hi demytt,&nbsp;Do you have an estimate of how much using the diff(T) variable contributes to your score?&nbsp;Differences in sampling frequencies across device types was one of the major sources of leakage encountered.</p>\n<p>I was thinking of ~$150 reward (after review that no leakage).&nbsp;</p>\n<p>&nbsp;</p>\n<p>&nbsp;</p>\n<p>&nbsp;</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "31721",
      "postDate": "09/28/2013 19:18:43",
      "content": "<p>I'll run my model without T and let you know the result. However, I think that the use of T shouldn't be considered as cheating in some cases, whereas it's obviously cheating in some other cases.</p>\n<p>For example, let's imagine you want to know if QuizDevice A corresponds to device 1, and let's assume we return the following score :</p>\n<p>isTrue_{A} = (mean(diff(T_A)) - mean(diff(T_1)))^2 + (mean(X_A) - mean(X_1))^2 + (mean(Y_A) - mean(Y_1))^2 + (mean(Z_A) - mean(Z_1))^2</p>\n<p>Do you consider this model as acceptable, or do you only want a model without any use of T ?</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "32250",
      "postDate": "10/11/2013 13:48:12",
      "content": "<p>My model has only mean(diff(T)) and std(diff(T)) and i'm not so bad. mean(diff(T)) let me improve my score of 0.03</p>\n<p>Use diff(T) is really leak exploit ? cause it could be specific to device in real life... no?</p>\n<p>&nbsp;</p>\n<p>I have a lot of other features with only X,Y or Z. </p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "32426",
      "postDate": "10/18/2013 22:54:31",
      "content": "<p>The problem is that everything leaks: X, Y, Z, timestamp interval, professed device, and the test data generation methodology. I have a FFT-based method that I believe should not be susceptible to leaks, and it does OK (~0.85), but I can't know for sure without a leak-free data set.</p>\n<p>&nbsp;</p>",
      "rawMarkdown": "",
      "votes": null
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  ],
  "comments": [
    {
      "id": 31064,
      "author_name": "dieselboy",
      "author_url": "",
      "post_date": "09/17/2013 21:50:52",
      "content": "<p>Hi Geoff</p>\n<p>I like your idea, and am looking forward to read more about how you want to implement it concretely.</p>\n<p>What demonstration do you have in mind? In general, you might need to take a look at model code and algorithm description in order to decide whether it fits your criteria. This is done by other Kaggle competitions, but I guess it takes time and effort.</p>\n<p>&nbsp;</p>\n<p>Personally, I think that my solution fits the legitimate criteria - without revealing too much I can say I use a classical supervised learning paradigm - construct features of the train set 4D signals, train a ML method, predict on the test data. Would this be legitimate for your criteria and constitute a solution useful for the competition organizers?</p>\n<p>Sometimes it is tricky to decide for some technical implementation details - e.g. usually using the training set distribution in a clever way belongs to good data science practice, but in this competition one of the problems is supposed to be the same distribution of train and test set.</p>\n<p>However, I have a feeling this is one of the smallest leaks, less serious than the time stamp issues and other mysterious leaks to which the top players hint at :-)</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31082,
      "author_name": "geoff3",
      "author_url": "",
      "post_date": "09/18/2013 13:39:31",
      "content": "<p>Hi Dieselboy,</p>\n<p>Thanks for responding to this invitation. I'm pleased to see a high scoring submission that didn't attempt to exploit the leakage. We would want to review your code &amp; maybe talk to ascertain that results are not impacted by leakage. If we can determine that score above 90% &nbsp;is attributable to legitimate features only, you will be rewarded. Please contact me directly to geoffkle@gmail.com, to discuss progressing this further.</p>\n<p>&nbsp;</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31364,
      "author_name": "sharadbanka",
      "author_url": "",
      "post_date": "09/23/2013 00:50:30",
      "content": "<p>Newbie here. Would love to understand what qualifies as a high score ? Are AUCs &gt; .9 achievable using only legitimate features ?</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31375,
      "author_name": "geoff3",
      "author_url": "",
      "post_date": "09/23/2013 05:48:23",
      "content": "<p>AUC &gt; 0.9</p>\n<p>This is what we would like to find out :)</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31504,
      "author_name": "dselivanov",
      "author_url": "",
      "post_date": "09/24/2013 16:19:31",
      "content": "<p>I use the same approach as&nbsp;Dieselboy, I think it is not too difficult to get score &gt;0.9 without using any leakages. I think moreover it is possible to get AUC&gt;0.9 even without time feature.</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31570,
      "author_name": "geoff3",
      "author_url": "",
      "post_date": "09/25/2013 21:33:26",
      "content": "<p>Hi diaman, would love to review your model, please contact me by email.</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31704,
      "author_name": "ademyttenaere",
      "author_url": "",
      "post_date": "09/28/2013 12:20:50",
      "content": "<p>[quote=Geoff;31082]</p>\n<p><span style=\"line-height: 1.4\">If we can determine that score above 90% &nbsp;is attributable to legitimate features only, you will be rewarded.&nbsp;</span>[/quote]</p>\n<p>&nbsp;</p>\n<p>Hi ! I just run my models without leakage and I got 0.90924 on leaderboard score. I used T the same way as the other variables, the only difference is that, instead using T I used diff(T).</p>\n<p>I wonder what kind of reward could we expect if we share you our leakage free models scoring more than 0.90 ?</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31711,
      "author_name": "geoff3",
      "author_url": "",
      "post_date": "09/28/2013 13:46:54",
      "content": "<p>Hi demytt,&nbsp;Do you have an estimate of how much using the diff(T) variable contributes to your score?&nbsp;Differences in sampling frequencies across device types was one of the major sources of leakage encountered.</p>\n<p>I was thinking of ~$150 reward (after review that no leakage).&nbsp;</p>\n<p>&nbsp;</p>\n<p>&nbsp;</p>\n<p>&nbsp;</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 31721,
      "author_name": "ademyttenaere",
      "author_url": "",
      "post_date": "09/28/2013 19:18:43",
      "content": "<p>I'll run my model without T and let you know the result. However, I think that the use of T shouldn't be considered as cheating in some cases, whereas it's obviously cheating in some other cases.</p>\n<p>For example, let's imagine you want to know if QuizDevice A corresponds to device 1, and let's assume we return the following score :</p>\n<p>isTrue_{A} = (mean(diff(T_A)) - mean(diff(T_1)))^2 + (mean(X_A) - mean(X_1))^2 + (mean(Y_A) - mean(Y_1))^2 + (mean(Z_A) - mean(Z_1))^2</p>\n<p>Do you consider this model as acceptable, or do you only want a model without any use of T ?</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 32250,
      "author_name": "nnnico",
      "author_url": "",
      "post_date": "10/11/2013 13:48:12",
      "content": "<p>My model has only mean(diff(T)) and std(diff(T)) and i'm not so bad. mean(diff(T)) let me improve my score of 0.03</p>\n<p>Use diff(T) is really leak exploit ? cause it could be specific to device in real life... no?</p>\n<p>&nbsp;</p>\n<p>I have a lot of other features with only X,Y or Z. </p>",
      "votes": null,
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    {
      "id": 32426,
      "author_name": "solorzano",
      "author_url": "",
      "post_date": "10/18/2013 22:54:31",
      "content": "<p>The problem is that everything leaks: X, Y, Z, timestamp interval, professed device, and the test data generation methodology. I have a FFT-based method that I believe should not be susceptible to leaks, and it does OK (~0.85), but I can't know for sure without a leak-free data set.</p>\n<p>&nbsp;</p>",
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