{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Summary\n",
    "From raw data that is a mixture of categoricals and numeric, featurize the categoricals using one hot encoding. Use tabular explainer to get explain object and then get raw feature importances"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Copyright (c) Microsoft Corporation. All rights reserved.\n",
    "\n",
    "Licensed under the MIT License."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Explain a model with the AML explain-model package on raw features\n",
    "\n",
    "1. Train a Logistic Regression model using Scikit-learn\n",
    "2. Run 'explain_model' with full dataset in local mode, which doesn't contact any Azure services.\n",
    "3. Run 'explain_model' with summarized dataset in local mode, which doesn't contact any Azure services.\n",
    "4. Visualize the global and local explanations with the visualization dashboard."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from sklearn.pipeline import Pipeline\n",
    "from sklearn.impute import SimpleImputer\n",
    "from sklearn.preprocessing import StandardScaler, OneHotEncoder\n",
    "from sklearn.linear_model import LogisticRegression\n",
    "from azureml.contrib.explain.model.tabular_explainer import TabularExplainer\n",
    "from sklearn_pandas import DataFrameMapper\n",
    "import pandas as pd\n",
    "import numpy as np"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "titanic_url = ('https://raw.githubusercontent.com/amueller/'\n",
    "               'scipy-2017-sklearn/091d371/notebooks/datasets/titanic3.csv')\n",
    "data = pd.read_csv(titanic_url)\n",
    "# fill missing values\n",
    "data = data.fillna(method=\"ffill\")\n",
    "data = data.fillna(method=\"bfill\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 1. Run model explainer locally with full data"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Similar to example [here](https://scikit-learn.org/stable/auto_examples/compose/plot_column_transformer_mixed_types.html#sphx-glr-auto-examples-compose-plot-column-transformer-mixed-types-py), use a subset of columns"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from sklearn.model_selection import train_test_split\n",
    "\n",
    "numeric_features = ['age', 'fare']\n",
    "categorical_features = ['embarked', 'sex', 'pclass']\n",
    "\n",
    "y = data['survived'].values\n",
    "X = data[categorical_features + numeric_features]\n",
    "\n",
    "x_train, x_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=42)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from sklearn.pipeline import Pipeline\n",
    "from sklearn.impute import SimpleImputer\n",
    "from sklearn.preprocessing import StandardScaler, OneHotEncoder\n",
    "from sklearn_pandas import DataFrameMapper\n",
    "\n",
    "# Impute and standardize the numeric features\n",
    "numeric_transformations = [([f], Pipeline(steps=[\n",
    "    ('imputer', SimpleImputer(strategy='median')),\n",
    "    ('scaler', StandardScaler())])) for f in numeric_features]\n",
    "    \n",
    "# One hot encode the categorical features    \n",
    "categorical_transformations = [([f], OneHotEncoder(handle_unknown='ignore', sparse=False)) for f in categorical_features]\n",
    "\n",
    "\n",
    "transformations = numeric_transformations + categorical_transformations\n",
    "\n",
    "# Append classifier to preprocessing pipeline.\n",
    "# Now we have a full prediction pipeline.\n",
    "clf = Pipeline(steps=[('preprocessor', DataFrameMapper(transformations)),\n",
    "                      ('classifier', LogisticRegression(solver='lbfgs'))])"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Train a Logistic Regression model, which you want to explain"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "model = clf.fit(x_train, y_train)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Explain predictions on your local machine"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "tabular_explainer = TabularExplainer(clf.steps[-1][1], initialization_examples=x_train, features=x_train.columns, transformations=transformations)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Passing in test dataset for evaluation examples - note it must be a representative sample of the original data\n",
    "# x_train can be passed as well, but with more examples explanations will take longer although they may be more accurate\n",
    "global_explanation = tabular_explainer.explain_global(x_test)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "sorted_global_importance_values = global_explanation.get_ranked_global_values()\n",
    "sorted_global_importance_names = global_explanation.get_ranked_global_names()\n",
    "dict(zip(sorted_global_importance_names, sorted_global_importance_values))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Explain overall model predictions as a collection of local (instance-level) explanations"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# explain the first member of the test set\n",
    "local_explanation = tabular_explainer.explain_local(x_test[:1])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# get the prediction for the first member of the test set and explain why model made that prediction\n",
    "prediction_value = clf.predict(x_test)[0]\n",
    "\n",
    "sorted_local_importance_values = local_explanation.get_ranked_local_values()[prediction_value]\n",
    "sorted_local_importance_names = local_explanation.get_ranked_local_names()[prediction_value]\n",
    "\n",
    "# Sorted local SHAP values\n",
    "print('ranked local importance values: {}'.format(sorted_local_importance_values))\n",
    "# Corresponding feature names\n",
    "print('ranked local importance names: {}'.format(sorted_local_importance_names))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 2. Load visualization dashboard"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from azureml.contrib.explain.model.visualize import ExplanationDashboard"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "ExplanationDashboard(global_explanation, model, x_test)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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   {
    "name": "mesameki"
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