{
  "id": 312117,
  "title": "✍✔📈📚 Top Evaluation Metrics for Reference 💥🎯💢",
  "url": "/competitions/h-and-m-personalized-fashion-recommendations/discussion/312117",
  "author_name": "",
  "post_date": "2022-03-10T13:36:49.251631400Z",
  "votes": 4,
  "comment_count": 6,
  "views": 0,
  "content": "<h6><a href=\"https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown\" target=\"_blank\">Reference Source :</a>Github</h6>\n<h2><strong> Some good Content on Evaluation metrics (link above)</strong></h2>\n<ul>\n<li>\n<p>Use <strong>test set</strong> get a reliable estimate of each models' performance.</p>\n</li>\n<li>\n<p><strong>Regression :</strong></p>\n<ul>\n<li>\n<p><strong>Mean Squared Error (MSE</strong>) or <strong>Mean Absolute Error (MAE</strong>). (<em>Lower values are better</em>)</p>\n<ul>\n<li>\n<p><strong>Mean Absolute Error</strong>.</p>\n<ul>\n<li>\n<p>MAE = sum( abs(predicted_i - actual_i) ) / total predictions</p>\n<ul>\n<li>sum of the absolute differences between predictions and actual values</li>\n</ul>\n</li>\n<li>\n<p>gives an idea of the magnitude of the error, but no idea of the direction</p>\n<ul>\n<li>over or under predicting</li>\n</ul>\n</li>\n<li>\n<p>0 indicates no error or perfect predictions</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Mean Squared Error</strong>.</p>\n<ul>\n<li>like the mean absolute error in that it provides a gross idea of the magnitude of error</li>\n</ul>\n</li>\n<li>\n<p>Root Mean Squared Error (or RMSE)</p>\n<ul>\n<li>\n<p>RMSE = sqrt( sum( (predicted_i - actual_i)^2 ) / total predictions)</p>\n</li>\n<li>\n<p>Taking the square root of the mean squared error converts the units back to the original units of the output variable and can be meaningful for description and presentation</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>R^2</strong>.</p>\n<ul>\n<li>\n<p>aka coefficient of determination</p>\n<ul>\n<li>statistical literature</li>\n</ul>\n</li>\n<li>\n<p>provides an indication of the goodness of fit of a set of predictions to the actual values</p>\n</li>\n<li>\n<p>0 and 1 for no-fit and perfect fit respectively</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Classification </strong></p>\n<ul>\n<li>\n<p><strong>Classification Accuracy</strong>.</p>\n<ul>\n<li>\n<p>accuracy = correct predictions / total predictions * 100</p>\n</li>\n<li>\n<p>number of correct predictions made as a ratio of all predictions made</p>\n</li>\n<li>\n<p>the most misused</p>\n</li>\n<li>\n<p>only suitable when there are an equal number of observations in each class and all predictions and prediction errors are equally important</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Logarithmic Loss</strong>.</p>\n<ul>\n<li>\n<p>evaluating the predictions of probabilities of membership to a given class</p>\n</li>\n<li>\n<p>scalar probability between 0 and 1</p>\n<ul>\n<li>measure of confidence for a prediction by an algorithm</li>\n</ul>\n</li>\n<li>\n<p>Predictions that are correct or incorrect are rewarded or punished proportionally to the confidence of the prediction</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Area Under ROC Curve (AUROC</strong>). (<em>Higher values are better</em>)</p>\n<ul>\n<li>\n<p><strong> Binary classification problems</strong></p>\n<ul>\n<li>A binary classification problem is really a trade-off between sensitivity and specificity&lt;</li>\n</ul>\n</li>\n<li>\n<p>represents a model’s ability to discriminate between positive and negative classes</p>\n</li>\n<li>\n<p>area of 1.0 represents a model that made all predictions perfectly</p>\n</li>\n<li>\n<p>An area of 0.5 represents a model as good as random&gt;</p>\n</li>\n<li>\n<p>can be broken down into sensitivity and specificity</p>\n<ul>\n<li>\n<p><strong>Sensitivity</strong></p>\n<ul>\n<li>\n<p>true positive rate also called the recall.</p>\n</li>\n<li>\n<p>number instances from the positive (first) class that actually predicted correctly.</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Specificity</strong></p>\n<ul>\n<li>true negative rate. Is the number of instances from the negative class (second) class that were actually predicted correctly.</li>\n</ul>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Confusion Matrix</strong>\n[![Confusion Matrix ](https://i.postimg.cc/nzT10K6x/E2-C3-EF03-6521-4-E65-99-DE-185-D4107-D2-A8.png)](https://postimg.cc/DJJszGvp)</p>\n<ul>\n<li>\n<p>Accuracy = (TP+TN)/(P+N)</p>\n</li>\n<li>\n<p>Precision = TP/(TP+FP)</p>\n</li>\n<li>\n<p>Recall/TP rate = TP/P</p>\n</li>\n<li>\n<p>FP Rate =  FP/N</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Unsupervised Learning - Evaluation</strong></p>\n<ul>\n<li>\n<p>Much harder to evaluate, depends on overall goal of the task</p>\n</li>\n<li>\n<p>Never had “Correct Labels” to compare to</p>\n</li>\n<li>\n<p>Cluster Homogeneity, Rand Index</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Reinforcement Learning - Evaluation</strong></p>\n<ul>\n<li>\n<p>Usually more obvious, since the “evaluation” is built into the actual training of the model.</p>\n</li>\n<li>\n<p>How well the model performs the task its assigned.</p>\n</li>\n</ul>\n</li>\n<li>\n<p>questions to help you pick the winning model:</p>\n<ul>\n<li>\n<p>Which model had the best performance on the test set? (<strong>performance</strong>)</p>\n</li>\n<li>\n<p>Does it perform well across various performance metrics? (<strong>robustness</strong>)</p>\n</li>\n<li>\n<p>Did it also have (one of) the best cross-validated scores from the training set? (<strong>consistency</strong>)</p>\n</li>\n<li>\n<p>Does it solve the original business problem? (<strong>win condition</strong>)</p>\n</li>\n</ul>\n</li>\n</ul>\n<p><a href=\"https://postimg.cc/PPbcSpWw\" target=\"_blank\"><img src=\"https://i.postimg.cc/DyRTy1mB/9-A1013-F6-6-E10-4-D3-C-8-E20-9399-D5-A6-AEA3.png\" alt=\"Quadratic Cost\"></a><br>\n<a href=\"https://postimg.cc/qhfxfQ0M\" target=\"_blank\"><img src=\"https://i.postimg.cc/xC8xzF4H/E68-F60-B8-FBFE-4-FA2-B29-D-7-B6-BFB07-FF72.png\" alt=\"Cross Entropy Loss\"></a></p>\n<h6><a href=\"https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown\" target=\"_blank\">Reference Source :</a>Github</h6>",
  "messages": [
    {
      "id": "1718073",
      "postDate": "03/10/2022 13:36:49",
      "content": "<h6><a href=\"https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown\" target=\"_blank\">Reference Source :</a>Github</h6>\n<h2><strong> Some good Content on Evaluation metrics (link above)</strong></h2>\n<ul>\n<li>\n<p>Use <strong>test set</strong> get a reliable estimate of each models' performance.</p>\n</li>\n<li>\n<p><strong>Regression :</strong></p>\n<ul>\n<li>\n<p><strong>Mean Squared Error (MSE</strong>) or <strong>Mean Absolute Error (MAE</strong>). (<em>Lower values are better</em>)</p>\n<ul>\n<li>\n<p><strong>Mean Absolute Error</strong>.</p>\n<ul>\n<li>\n<p>MAE = sum( abs(predicted_i - actual_i) ) / total predictions</p>\n<ul>\n<li>sum of the absolute differences between predictions and actual values</li>\n</ul>\n</li>\n<li>\n<p>gives an idea of the magnitude of the error, but no idea of the direction</p>\n<ul>\n<li>over or under predicting</li>\n</ul>\n</li>\n<li>\n<p>0 indicates no error or perfect predictions</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Mean Squared Error</strong>.</p>\n<ul>\n<li>like the mean absolute error in that it provides a gross idea of the magnitude of error</li>\n</ul>\n</li>\n<li>\n<p>Root Mean Squared Error (or RMSE)</p>\n<ul>\n<li>\n<p>RMSE = sqrt( sum( (predicted_i - actual_i)^2 ) / total predictions)</p>\n</li>\n<li>\n<p>Taking the square root of the mean squared error converts the units back to the original units of the output variable and can be meaningful for description and presentation</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>R^2</strong>.</p>\n<ul>\n<li>\n<p>aka coefficient of determination</p>\n<ul>\n<li>statistical literature</li>\n</ul>\n</li>\n<li>\n<p>provides an indication of the goodness of fit of a set of predictions to the actual values</p>\n</li>\n<li>\n<p>0 and 1 for no-fit and perfect fit respectively</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Classification </strong></p>\n<ul>\n<li>\n<p><strong>Classification Accuracy</strong>.</p>\n<ul>\n<li>\n<p>accuracy = correct predictions / total predictions * 100</p>\n</li>\n<li>\n<p>number of correct predictions made as a ratio of all predictions made</p>\n</li>\n<li>\n<p>the most misused</p>\n</li>\n<li>\n<p>only suitable when there are an equal number of observations in each class and all predictions and prediction errors are equally important</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Logarithmic Loss</strong>.</p>\n<ul>\n<li>\n<p>evaluating the predictions of probabilities of membership to a given class</p>\n</li>\n<li>\n<p>scalar probability between 0 and 1</p>\n<ul>\n<li>measure of confidence for a prediction by an algorithm</li>\n</ul>\n</li>\n<li>\n<p>Predictions that are correct or incorrect are rewarded or punished proportionally to the confidence of the prediction</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Area Under ROC Curve (AUROC</strong>). (<em>Higher values are better</em>)</p>\n<ul>\n<li>\n<p><strong> Binary classification problems</strong></p>\n<ul>\n<li>A binary classification problem is really a trade-off between sensitivity and specificity&lt;</li>\n</ul>\n</li>\n<li>\n<p>represents a model’s ability to discriminate between positive and negative classes</p>\n</li>\n<li>\n<p>area of 1.0 represents a model that made all predictions perfectly</p>\n</li>\n<li>\n<p>An area of 0.5 represents a model as good as random&gt;</p>\n</li>\n<li>\n<p>can be broken down into sensitivity and specificity</p>\n<ul>\n<li>\n<p><strong>Sensitivity</strong></p>\n<ul>\n<li>\n<p>true positive rate also called the recall.</p>\n</li>\n<li>\n<p>number instances from the positive (first) class that actually predicted correctly.</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Specificity</strong></p>\n<ul>\n<li>true negative rate. Is the number of instances from the negative class (second) class that were actually predicted correctly.</li>\n</ul>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Confusion Matrix</strong>\n[![Confusion Matrix ](https://i.postimg.cc/nzT10K6x/E2-C3-EF03-6521-4-E65-99-DE-185-D4107-D2-A8.png)](https://postimg.cc/DJJszGvp)</p>\n<ul>\n<li>\n<p>Accuracy = (TP+TN)/(P+N)</p>\n</li>\n<li>\n<p>Precision = TP/(TP+FP)</p>\n</li>\n<li>\n<p>Recall/TP rate = TP/P</p>\n</li>\n<li>\n<p>FP Rate =  FP/N</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Unsupervised Learning - Evaluation</strong></p>\n<ul>\n<li>\n<p>Much harder to evaluate, depends on overall goal of the task</p>\n</li>\n<li>\n<p>Never had “Correct Labels” to compare to</p>\n</li>\n<li>\n<p>Cluster Homogeneity, Rand Index</p>\n</li>\n</ul>\n</li>\n<li>\n<p><strong>Reinforcement Learning - Evaluation</strong></p>\n<ul>\n<li>\n<p>Usually more obvious, since the “evaluation” is built into the actual training of the model.</p>\n</li>\n<li>\n<p>How well the model performs the task its assigned.</p>\n</li>\n</ul>\n</li>\n<li>\n<p>questions to help you pick the winning model:</p>\n<ul>\n<li>\n<p>Which model had the best performance on the test set? (<strong>performance</strong>)</p>\n</li>\n<li>\n<p>Does it perform well across various performance metrics? (<strong>robustness</strong>)</p>\n</li>\n<li>\n<p>Did it also have (one of) the best cross-validated scores from the training set? (<strong>consistency</strong>)</p>\n</li>\n<li>\n<p>Does it solve the original business problem? (<strong>win condition</strong>)</p>\n</li>\n</ul>\n</li>\n</ul>\n<p><a href=\"https://postimg.cc/PPbcSpWw\" target=\"_blank\"><img src=\"https://i.postimg.cc/DyRTy1mB/9-A1013-F6-6-E10-4-D3-C-8-E20-9399-D5-A6-AEA3.png\" alt=\"Quadratic Cost\"></a><br>\n<a href=\"https://postimg.cc/qhfxfQ0M\" target=\"_blank\"><img src=\"https://i.postimg.cc/xC8xzF4H/E68-F60-B8-FBFE-4-FA2-B29-D-7-B6-BFB07-FF72.png\" alt=\"Cross Entropy Loss\"></a></p>\n<h6><a href=\"https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown\" target=\"_blank\">Reference Source :</a>Github</h6>",
      "rawMarkdown": "###### [Reference Source :]( https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown)Github\n \n\n## <strong> Some good Content on Evaluation metrics (link above)</strong>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Use <strong>test set</strong> get a reliable estimate of each models' performance.</p>\n</li>\n<li>\n<p dir=\"auto\"><strong>Regression :</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Mean Squared Error (MSE</strong>) or <strong>Mean Absolute Error (MAE</strong>). (<em>Lower values are better</em>)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Mean Absolute Error</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">MAE = sum( abs(predicted_i - actual_i) ) / total predictions</p>\n<ul dir=\"auto\">\n<li>sum of the absolute differences between predictions and actual values</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">gives an idea of the magnitude of the error, but no idea of the direction</p>\n<ul dir=\"auto\">\n<li>over or under predicting</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">0 indicates no error or perfect predictions</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Mean Squared Error</strong>.</p>\n<ul dir=\"auto\">\n<li>like the mean absolute error in that it provides a gross idea of the magnitude of error</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">Root Mean Squared Error (or RMSE)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">RMSE = sqrt( sum( (predicted_i - actual_i)^2 ) / total predictions)</p>\n</li>\n<li>\n<p dir=\"auto\">Taking the square root of the mean squared error converts the units back to the original units of the output variable and can be meaningful for description and presentation</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>R^2</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">aka coefficient of determination</p>\n<ul dir=\"auto\">\n<li>statistical literature</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">provides an indication of the goodness of fit of a set of predictions to the actual values</p>\n</li>\n<li>\n<p dir=\"auto\">0 and 1 for no-fit and perfect fit respectively</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Classification </strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Classification Accuracy</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">accuracy = correct predictions / total predictions * 100</p>\n</li>\n<li>\n<p dir=\"auto\">number of correct predictions made as a ratio of all predictions made</p>\n</li>\n<li>\n<p dir=\"auto\">the most misused</p>\n</li>\n<li>\n<p dir=\"auto\">only suitable when there are an equal number of observations in each class and all predictions and prediction errors are equally important</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Logarithmic Loss</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">evaluating the predictions of probabilities of membership to a given class</p>\n</li>\n<li>\n<p dir=\"auto\">scalar probability between 0 and 1</p>\n<ul dir=\"auto\">\n<li>measure of confidence for a prediction by an algorithm</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">Predictions that are correct or incorrect are rewarded or punished proportionally to the confidence of the prediction</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Area Under ROC Curve (AUROC</strong>). (<em>Higher values are better</em>)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong> Binary classification problems</strong></p>\n<ul dir=\"auto\">\n<li>A binary classification problem is really a trade-off between sensitivity and specificity<</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">represents a model’s ability to discriminate between positive and negative classes</p>\n</li>\n<li>\n<p dir=\"auto\">area of 1.0 represents a model that made all predictions perfectly</p>\n</li>\n<li>\n<p dir=\"auto\">An area of 0.5 represents a model as good as random></p>\n</li>\n<li>\n<p dir=\"auto\">can be broken down into sensitivity and specificity</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Sensitivity</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">true positive rate also called the recall.</p>\n</li>\n<li>\n<p dir=\"auto\">number instances from the positive (first) class that actually predicted correctly.</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Specificity</strong></p>\n<ul dir=\"auto\">\n<li>true negative rate. Is the number of instances from the negative class (second) class that were actually predicted correctly.</li>\n</ul>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Confusion Matrix</strong>\n[![Confusion Matrix ](https://i.postimg.cc/nzT10K6x/E2-C3-EF03-6521-4-E65-99-DE-185-D4107-D2-A8.png)](https://postimg.cc/DJJszGvp)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Accuracy = (TP+TN)/(P+N)</p>\n</li>\n<li>\n<p dir=\"auto\">Precision = TP/(TP+FP)</p>\n</li>\n<li>\n<p dir=\"auto\">Recall/TP rate = TP/P</p>\n</li>\n<li>\n<p dir=\"auto\">FP Rate =  FP/N</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Unsupervised Learning - Evaluation</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Much harder to evaluate, depends on overall goal of the task</p>\n</li>\n<li>\n<p dir=\"auto\">Never had “Correct Labels” to compare to</p>\n</li>\n<li>\n<p dir=\"auto\">Cluster Homogeneity, Rand Index</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Reinforcement Learning - Evaluation</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Usually more obvious, since the “evaluation” is built into the actual training of the model.</p>\n</li>\n<li>\n<p dir=\"auto\">How well the model performs the task its assigned.</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">questions to help you pick the winning model:</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Which model had the best performance on the test set? (<strong>performance</strong>)</p>\n</li>\n<li>\n<p dir=\"auto\">Does it perform well across various performance metrics? (<strong>robustness</strong>)</p>\n</li>\n<li>\n<p dir=\"auto\">Did it also have (one of) the best cross-validated scores from the training set? (<strong>consistency</strong>)</p>\n</li>\n<li>\n<p dir=\"auto\">Does it solve the original business problem? (<strong>win condition</strong>)</p>\n</li>\n</ul>\n</li>\n</ul>\n[![Quadratic Cost](https://i.postimg.cc/DyRTy1mB/9-A1013-F6-6-E10-4-D3-C-8-E20-9399-D5-A6-AEA3.png)](https://postimg.cc/PPbcSpWw)\n[![Cross Entropy Loss](https://i.postimg.cc/xC8xzF4H/E68-F60-B8-FBFE-4-FA2-B29-D-7-B6-BFB07-FF72.png)](https://postimg.cc/qhfxfQ0M)\n\n###### [Reference Source :]( https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown)Github",
      "votes": null
    },
    {
      "id": "1718216",
      "postDate": "03/10/2022 15:54:29",
      "content": "<p>Very useful information, thanks</p>",
      "rawMarkdown": "Very useful information, thanks",
      "votes": null
    },
    {
      "id": "1718220",
      "postDate": "03/10/2022 15:56:46",
      "content": "<p>Thank you <a href=\"https://www.kaggle.com/djacon\" target=\"_blank\">@djacon</a> </p>",
      "rawMarkdown": "Thank you @djacon",
      "votes": null
    },
    {
      "id": "1718258",
      "postDate": "03/10/2022 16:59:25",
      "content": "<p>Compiled version of the knowledge accompanied by the alignment of the concepts as per their hierarchy really helps. <br>\nThanks for sharing ^_^</p>",
      "rawMarkdown": "Compiled version of the knowledge accompanied by the alignment of the concepts as per their hierarchy really helps. \nThanks for sharing ^_^",
      "votes": null
    },
    {
      "id": "1718292",
      "postDate": "03/10/2022 17:44:34",
      "content": "<p>Thanks <a href=\"https://www.kaggle.com/surajjha101\" target=\"_blank\">@surajjha101</a> </p>",
      "rawMarkdown": "Thanks @surajjha101",
      "votes": null
    },
    {
      "id": "1721410",
      "postDate": "03/13/2022 16:58:01",
      "content": "<p>Thanks for sharing :D <a href=\"https://www.kaggle.com/kalilurrahman\" target=\"_blank\">@kalilurrahman</a> </p>",
      "rawMarkdown": "Thanks for sharing :D @kalilurrahman",
      "votes": null
    },
    {
      "id": "1724237",
      "postDate": "03/16/2022 05:37:27",
      "content": "<p>Thank you <a href=\"https://www.kaggle.com/andriyuru\" target=\"_blank\">@andriyuru</a> </p>",
      "rawMarkdown": "Thank you @andriyuru",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 1718216,
      "author_name": "djacon",
      "author_url": "",
      "post_date": "03/10/2022 15:54:29",
      "content": "<p>Very useful information, thanks</p>",
      "votes": null,
      "replies": [
        {
          "id": 1718220,
          "author_name": "kalilurrahman",
          "author_url": "",
          "post_date": "03/10/2022 15:56:46",
          "content": "<p>Thank you <a href=\"https://www.kaggle.com/djacon\" target=\"_blank\">@djacon</a> </p>",
          "votes": null,
          "replies": []
        }
      ]
    },
    {
      "id": 1718258,
      "author_name": "surajjha101",
      "author_url": "",
      "post_date": "03/10/2022 16:59:25",
      "content": "<p>Compiled version of the knowledge accompanied by the alignment of the concepts as per their hierarchy really helps. <br>\nThanks for sharing ^_^</p>",
      "votes": null,
      "replies": [
        {
          "id": 1718292,
          "author_name": "kalilurrahman",
          "author_url": "",
          "post_date": "03/10/2022 17:44:34",
          "content": "<p>Thanks <a href=\"https://www.kaggle.com/surajjha101\" target=\"_blank\">@surajjha101</a> </p>",
          "votes": null,
          "replies": []
        }
      ]
    },
    {
      "id": 1721410,
      "author_name": "",
      "author_url": "",
      "post_date": "03/13/2022 16:58:01",
      "content": "<p>Thanks for sharing :D <a href=\"https://www.kaggle.com/kalilurrahman\" target=\"_blank\">@kalilurrahman</a> </p>",
      "votes": null,
      "replies": [
        {
          "id": 1724237,
          "author_name": "kalilurrahman",
          "author_url": "",
          "post_date": "03/16/2022 05:37:27",
          "content": "<p>Thank you <a href=\"https://www.kaggle.com/andriyuru\" target=\"_blank\">@andriyuru</a> </p>",
          "votes": null,
          "replies": []
        }
      ]
    }
  ],
  "raw_markdown_by_id": {
    "1718073": "###### [Reference Source :]( https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown)Github\n \n\n## <strong> Some good Content on Evaluation metrics (link above)</strong>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Use <strong>test set</strong> get a reliable estimate of each models' performance.</p>\n</li>\n<li>\n<p dir=\"auto\"><strong>Regression :</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Mean Squared Error (MSE</strong>) or <strong>Mean Absolute Error (MAE</strong>). (<em>Lower values are better</em>)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Mean Absolute Error</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">MAE = sum( abs(predicted_i - actual_i) ) / total predictions</p>\n<ul dir=\"auto\">\n<li>sum of the absolute differences between predictions and actual values</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">gives an idea of the magnitude of the error, but no idea of the direction</p>\n<ul dir=\"auto\">\n<li>over or under predicting</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">0 indicates no error or perfect predictions</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Mean Squared Error</strong>.</p>\n<ul dir=\"auto\">\n<li>like the mean absolute error in that it provides a gross idea of the magnitude of error</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">Root Mean Squared Error (or RMSE)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">RMSE = sqrt( sum( (predicted_i - actual_i)^2 ) / total predictions)</p>\n</li>\n<li>\n<p dir=\"auto\">Taking the square root of the mean squared error converts the units back to the original units of the output variable and can be meaningful for description and presentation</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>R^2</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">aka coefficient of determination</p>\n<ul dir=\"auto\">\n<li>statistical literature</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">provides an indication of the goodness of fit of a set of predictions to the actual values</p>\n</li>\n<li>\n<p dir=\"auto\">0 and 1 for no-fit and perfect fit respectively</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Classification </strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Classification Accuracy</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">accuracy = correct predictions / total predictions * 100</p>\n</li>\n<li>\n<p dir=\"auto\">number of correct predictions made as a ratio of all predictions made</p>\n</li>\n<li>\n<p dir=\"auto\">the most misused</p>\n</li>\n<li>\n<p dir=\"auto\">only suitable when there are an equal number of observations in each class and all predictions and prediction errors are equally important</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Logarithmic Loss</strong>.</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">evaluating the predictions of probabilities of membership to a given class</p>\n</li>\n<li>\n<p dir=\"auto\">scalar probability between 0 and 1</p>\n<ul dir=\"auto\">\n<li>measure of confidence for a prediction by an algorithm</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">Predictions that are correct or incorrect are rewarded or punished proportionally to the confidence of the prediction</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Area Under ROC Curve (AUROC</strong>). (<em>Higher values are better</em>)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong> Binary classification problems</strong></p>\n<ul dir=\"auto\">\n<li>A binary classification problem is really a trade-off between sensitivity and specificity<</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">represents a model’s ability to discriminate between positive and negative classes</p>\n</li>\n<li>\n<p dir=\"auto\">area of 1.0 represents a model that made all predictions perfectly</p>\n</li>\n<li>\n<p dir=\"auto\">An area of 0.5 represents a model as good as random></p>\n</li>\n<li>\n<p dir=\"auto\">can be broken down into sensitivity and specificity</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\"><strong>Sensitivity</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">true positive rate also called the recall.</p>\n</li>\n<li>\n<p dir=\"auto\">number instances from the positive (first) class that actually predicted correctly.</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Specificity</strong></p>\n<ul dir=\"auto\">\n<li>true negative rate. Is the number of instances from the negative class (second) class that were actually predicted correctly.</li>\n</ul>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Confusion Matrix</strong>\n[![Confusion Matrix ](https://i.postimg.cc/nzT10K6x/E2-C3-EF03-6521-4-E65-99-DE-185-D4107-D2-A8.png)](https://postimg.cc/DJJszGvp)</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Accuracy = (TP+TN)/(P+N)</p>\n</li>\n<li>\n<p dir=\"auto\">Precision = TP/(TP+FP)</p>\n</li>\n<li>\n<p dir=\"auto\">Recall/TP rate = TP/P</p>\n</li>\n<li>\n<p dir=\"auto\">FP Rate =  FP/N</p>\n</li>\n</ul>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Unsupervised Learning - Evaluation</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Much harder to evaluate, depends on overall goal of the task</p>\n</li>\n<li>\n<p dir=\"auto\">Never had “Correct Labels” to compare to</p>\n</li>\n<li>\n<p dir=\"auto\">Cluster Homogeneity, Rand Index</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\"><strong>Reinforcement Learning - Evaluation</strong></p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Usually more obvious, since the “evaluation” is built into the actual training of the model.</p>\n</li>\n<li>\n<p dir=\"auto\">How well the model performs the task its assigned.</p>\n</li>\n</ul>\n</li>\n<li>\n<p dir=\"auto\">questions to help you pick the winning model:</p>\n<ul dir=\"auto\">\n<li>\n<p dir=\"auto\">Which model had the best performance on the test set? (<strong>performance</strong>)</p>\n</li>\n<li>\n<p dir=\"auto\">Does it perform well across various performance metrics? (<strong>robustness</strong>)</p>\n</li>\n<li>\n<p dir=\"auto\">Did it also have (one of) the best cross-validated scores from the training set? (<strong>consistency</strong>)</p>\n</li>\n<li>\n<p dir=\"auto\">Does it solve the original business problem? (<strong>win condition</strong>)</p>\n</li>\n</ul>\n</li>\n</ul>\n[![Quadratic Cost](https://i.postimg.cc/DyRTy1mB/9-A1013-F6-6-E10-4-D3-C-8-E20-9399-D5-A6-AEA3.png)](https://postimg.cc/PPbcSpWw)\n[![Cross Entropy Loss](https://i.postimg.cc/xC8xzF4H/E68-F60-B8-FBFE-4-FA2-B29-D-7-B6-BFB07-FF72.png)](https://postimg.cc/qhfxfQ0M)\n\n###### [Reference Source :]( https://github.com/ankschoubey/Huge-Data-Science-Mind-Map/blob/master/Data%20Science%20Markdown%20with%20Images.textbundle/text.markdown)Github",
    "1718216": "Very useful information, thanks",
    "1718220": "Thank you @djacon",
    "1718258": "Compiled version of the knowledge accompanied by the alignment of the concepts as per their hierarchy really helps. \nThanks for sharing ^_^",
    "1718292": "Thanks @surajjha101",
    "1721410": "Thanks for sharing :D @kalilurrahman",
    "1724237": "Thank you @andriyuru"
  },
  "source": "meta"
}