From e3624527366f753699f56e57009cd0cfb44b31d5 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=2E=20Fernando=20S=C3=A1nchez?= Date: Thu, 20 Apr 2017 13:18:44 +0200 Subject: [PATCH] --- 4_4.ipynb | 439 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ README.md | 12 ++ 2 files changed, 451 insertions(+) create mode 100644 4_4.ipynb create mode 100644 README.md diff --git a/4_4.ipynb b/4_4.ipynb new file mode 100644 index 0000000..5a54a2e --- /dev/null +++ b/4_4.ipynb @@ -0,0 +1,439 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "![](images/EscUpmPolit_p.gif \"UPM\")" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Course Notes for Learning Intelligent Systems" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "Department of Telematic Engineering Systems, Universidad Politécnica de Madrid, © 2016 Carlos A. Iglesias" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Text Classification" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Table of Contents\n", + "* [Objectives](#Objectives)\n", + "* [Corpus](#Corpus)\n", + "* [Classifier](#Classifier)" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Objectives" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "In this session we provide a quick overview of how the vector models we have presented previously can be used for applying machine learning techniques, such as classification.\n", + "\n", + "The main objectives of this session are:\n", + "* Understand how to apply machine learning techniques on textual sources\n", + "* Learn the facilities provided by scikit-learn" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Corpus" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "We are going to use on of the corpus that come prepackaged with Scikit-learn: the [20 newsgroup datase](http://qwone.com/~jason/20Newsgroups/). The 20 newsgroup dataset contains 20k documents that belong to 20 topics.\n", + "\n", + "We inspect now the corpus using the facilities from Scikit-learn, as explain in [scikit-learn](http://scikit-learn.org/stable/datasets/twenty_newsgroups.html#newsgroups)" + ] + }, + { + "cell_type": "code", + "execution_count": 1, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "['alt.atheism', 'comp.graphics', 'comp.os.ms-windows.misc', 'comp.sys.ibm.pc.hardware', 'comp.sys.mac.hardware', 'comp.windows.x', 'misc.forsale', 'rec.autos', 'rec.motorcycles', 'rec.sport.baseball', 'rec.sport.hockey', 'sci.crypt', 'sci.electronics', 'sci.med', 'sci.space', 'soc.religion.christian', 'talk.politics.guns', 'talk.politics.mideast', 'talk.politics.misc', 'talk.religion.misc']\n" + ] + } + ], + "source": [ + "from sklearn.datasets import fetch_20newsgroups\n", + "\n", + "# We remove metadata to avoid bias in the classification\n", + "newsgroups_train = fetch_20newsgroups(subset='train', remove=('headers', 'footers', 'quotes'))\n", + "newsgroups_test = fetch_20newsgroups(subset='test', remove=('headers', 'footers', 'quotes'))\n", + "\n", + "# print categories\n", + "print(list(newsgroups_train.target_names))" + ] + }, + { + "cell_type": "code", + "execution_count": 2, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "20\n" + ] + } + ], + "source": [ + "#Number of categories\n", + "print(len(newsgroups_train.target_names))" + ] + }, + { + "cell_type": "code", + "execution_count": 3, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Category id 4 comp.sys.mac.hardware\n", + "Doc A fair number of brave souls who upgraded their SI clock oscillator have\n", + "shared their experiences for this poll. Please send a brief message detailing\n", + "your experiences with the procedure. Top speed attained, CPU rated speed,\n", + "add on cards and adapters, heat sinks, hour of usage per day, floppy disk\n", + "functionality with 800 and 1.4 m floppies are especially requested.\n", + "\n", + "I will be summarizing in the next two days, so please add to the network\n", + "knowledge base if you have done the clock upgrade and haven't answered this\n", + "poll. Thanks.\n" + ] + } + ], + "source": [ + "# Show a document\n", + "docid = 1\n", + "doc = newsgroups_train.data[docid]\n", + "cat = newsgroups_train.target[docid]\n", + "\n", + "print(\"Category id \" + str(cat) + \" \" + newsgroups_train.target_names[cat])\n", + "print(\"Doc \" + doc)" + ] + }, + { + "cell_type": "code", + "execution_count": 4, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "(11314,)" + ] + }, + "execution_count": 4, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "#Number of files\n", + "newsgroups_train.filenames.shape" + ] + }, + { + "cell_type": "code", + "execution_count": 5, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "(11314, 101322)" + ] + }, + "execution_count": 5, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "# Obtain a vector\n", + "\n", + "from sklearn.feature_extraction.text import TfidfVectorizer\n", + "\n", + "vectorizer = TfidfVectorizer(analyzer='word', stop_words='english')\n", + "\n", + "vectors_train = vectorizer.fit_transform(newsgroups_train.data)\n", + "vectors_train.shape" + ] + }, + { + "cell_type": "code", + "execution_count": 6, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "66.802987449178" + ] + }, + "execution_count": 6, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "# The tf-idf vectors are very sparse with an average of 66 non zero components in 101.323 dimensions (.06%)\n", + "vectors_train.nnz / float(vectors_train.shape[0])" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Classifier" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "Once we have vectors, we can create classifiers (or other machine learning algorithms such as clustering) as we saw previously in the notebooks of machine learning with scikit-learn." + ] + }, + { + "cell_type": "code", + "execution_count": 7, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "0.69545360719001303" + ] + }, + "execution_count": 7, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "from sklearn.naive_bayes import MultinomialNB\n", + "\n", + "from sklearn import metrics\n", + "\n", + "\n", + "# We learn the vocabulary (fit) with the train dataset and transform into vectors (fit_transform)\n", + "# Nevertheless, we only transform the test dataset into vectors (transform, not fit_transform)\n", + "\n", + "model = MultinomialNB(alpha=.01)\n", + "model.fit(vectors_train, newsgroups_train.target)\n", + "\n", + "vectors_test = vectorizer.transform(newsgroups_test.data)\n", + "pred = model.predict(vectors_test)\n", + "\n", + "metrics.f1_score(newsgroups_test.target, pred, average='weighted')\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "We are getting F1 of 0.69 for 20 categories this could be improved (optimization, preprocessing, etc.)" + ] + }, + { + "cell_type": "code", + "execution_count": 8, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "dimensionality: 101322\n", + "density: 1.000000\n" + ] + } + ], + "source": [ + "from sklearn.utils.extmath import density\n", + "\n", + "print(\"dimensionality: %d\" % model.coef_.shape[1])\n", + "print(\"density: %f\" % density(model.coef_))" + ] + }, + { + "cell_type": "code", + "execution_count": 9, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "alt.atheism: islam atheists say just religion atheism think don people god\n", + "comp.graphics: looking format 3d know program file files thanks image graphics\n", + "comp.os.ms-windows.misc: card problem thanks driver drivers use files dos file windows\n", + "comp.sys.ibm.pc.hardware: monitor disk thanks pc ide controller bus card scsi drive\n", + "comp.sys.mac.hardware: know monitor does quadra simms thanks problem drive apple mac\n", + "comp.windows.x: using windows x11r5 use application thanks widget server motif window\n", + "misc.forsale: asking email sell price condition new shipping offer 00 sale\n", + "rec.autos: don ford new good dealer just engine like cars car\n", + "rec.motorcycles: don just helmet riding like motorcycle ride bikes dod bike\n", + "rec.sport.baseball: braves players pitching hit runs games game baseball team year\n", + "rec.sport.hockey: league year nhl games season players play hockey team game\n", + "sci.crypt: people use escrow nsa keys government chip clipper encryption key\n", + "sci.electronics: don thanks voltage used know does like circuit power use\n", + "sci.med: skepticism cadre dsl banks chastity n3jxp pitt gordon geb msg\n", + "sci.space: just lunar earth shuttle like moon launch orbit nasa space\n", + "soc.religion.christian: believe faith christian christ bible people christians church jesus god\n", + "talk.politics.guns: just law firearms government fbi don weapons people guns gun\n", + "talk.politics.mideast: said arabs arab turkish people armenians armenian jews israeli israel\n", + "talk.politics.misc: know state clinton president just think tax don government people\n", + "talk.religion.misc: think don koresh objective christians bible people christian jesus god\n" + ] + } + ], + "source": [ + "# We can review the top features per topic in Bayes (attribute coef_)\n", + "import numpy as np\n", + "\n", + "def show_top10(classifier, vectorizer, categories):\n", + " feature_names = np.asarray(vectorizer.get_feature_names())\n", + " for i, category in enumerate(categories):\n", + " top10 = np.argsort(classifier.coef_[i])[-10:]\n", + " print(\"%s: %s\" % (category, \" \".join(feature_names[top10])))\n", + "\n", + " \n", + "show_top10(model, vectorizer, newsgroups_train.target_names)" + ] + }, + { + "cell_type": "code", + "execution_count": 10, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "[ 2 15]\n", + "['comp.os.ms-windows.misc', 'soc.religion.christian']\n" + ] + } + ], + "source": [ + "# We try the classifier in two new docs\n", + "\n", + "new_docs = ['This is a survey of PC computers', 'God is love']\n", + "new_vectors = vectorizer.transform(new_docs)\n", + "\n", + "pred_docs = model.predict(new_vectors)\n", + "print(pred_docs)\n", + "print([newsgroups_train.target_names[i] for i in pred_docs])" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## References\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "* [NLTK Book. Natural Language Processing with Python. Steven Bird, Ewan Klein, and Edward Loper. O'Reilly Media, 2009 ](http://www.nltk.org/book_1ed/)\n", + "* [NLTK Essentials, Nitin Hardeniya, Packt Publishing, 2015](http://proquest.safaribooksonline.com/search?q=NLTK%20Essentials)" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Licence" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "The notebook is freely licensed under under the [Creative Commons Attribution Share-Alike license](https://creativecommons.org/licenses/by/2.0/). \n", + "\n", + "© 2016 Carlos A. Iglesias, Universidad Politécnica de Madrid." + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 3", + "language": "python", + "name": "python3" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 3 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython3", + "version": "3.5.2" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} diff --git a/README.md b/README.md new file mode 100644 index 0000000..b4b4e40 --- /dev/null +++ b/README.md @@ -0,0 +1,12 @@ +Clone the repo +``` +git clone https://github.com/gsi-upm/sitc +``` + +Run jupyter either through the `jupyter notebook` command, or with docker: + +``` +docker run -v $PWD/:/home/jovyan/work/ -p 8888:8888 jupyter/scipy-notebook +``` + +Visit the URL you'll get, or copy the code. \ No newline at end of file