spam.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {
    "collapsed": true
   },
   "source": [
    "### Naive Bayes classification example from the book \"Principles of Data Science\"\n",
    "```\n",
    "P(spam|<sentence>) = P(<sentence>|spam) * P(spam) / P(<sentence>)\n",
    "P(non-spam|<sentence>) = P(<sentence>|non-spam) * P(non-spam) / P(<sentence>)\n",
    "```"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import pandas as pd\n",
    "import sklearn"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>label</th>\n",
       "      <th>msg</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>ham</td>\n",
       "      <td>Go until jurong point, crazy.. Available only ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ok lar... Joking wif u oni...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>spam</td>\n",
       "      <td>Free entry in 2 a wkly comp to win FA Cup fina...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>ham</td>\n",
       "      <td>U dun say so early hor... U c already then say...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>ham</td>\n",
       "      <td>Nah I don't think he goes to usf, he lives aro...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>spam</td>\n",
       "      <td>FreeMsg Hey there darling it's been 3 week's n...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>ham</td>\n",
       "      <td>Even my brother is not like to speak with me. ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>ham</td>\n",
       "      <td>As per your request 'Melle Melle (Oru Minnamin...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>spam</td>\n",
       "      <td>WINNER!! As a valued network customer you have...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>spam</td>\n",
       "      <td>Had your mobile 11 months or more? U R entitle...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>ham</td>\n",
       "      <td>I'm gonna be home soon and i don't want to tal...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>spam</td>\n",
       "      <td>SIX chances to win CASH! From 100 to 20,000 po...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>spam</td>\n",
       "      <td>URGENT! You have won a 1 week FREE membership ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>ham</td>\n",
       "      <td>I've been searching for the right words to tha...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>ham</td>\n",
       "      <td>I HAVE A DATE ON SUNDAY WITH WILL!!</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>spam</td>\n",
       "      <td>XXXMobileMovieClub: To use your credit, click ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>ham</td>\n",
       "      <td>Oh k...i'm watching here:)</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>ham</td>\n",
       "      <td>Eh u remember how 2 spell his name... Yes i di...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>ham</td>\n",
       "      <td>Fine if thats the way u feel. Thats the way ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>spam</td>\n",
       "      <td>England v Macedonia - dont miss the goals/team...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>ham</td>\n",
       "      <td>Is that seriously how you spell his name?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>ham</td>\n",
       "      <td>I‘m going to try for 2 months ha ha only joking</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>ham</td>\n",
       "      <td>So ü pay first lar... Then when is da stock co...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>ham</td>\n",
       "      <td>Aft i finish my lunch then i go str down lor. ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ffffffffff. Alright no way I can meet up with ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>ham</td>\n",
       "      <td>Just forced myself to eat a slice. I'm really ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>ham</td>\n",
       "      <td>Lol your always so convincing.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>ham</td>\n",
       "      <td>Did you catch the bus ? Are you frying an egg ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>ham</td>\n",
       "      <td>I'm back &amp;amp; we're packing the car now, I'll...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ahhh. Work. I vaguely remember that! What does...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5542</th>\n",
       "      <td>ham</td>\n",
       "      <td>Armand says get your ass over to epsilon</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5543</th>\n",
       "      <td>ham</td>\n",
       "      <td>U still havent got urself a jacket ah?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5544</th>\n",
       "      <td>ham</td>\n",
       "      <td>I'm taking derek &amp;amp; taylor to walmart, if I...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5545</th>\n",
       "      <td>ham</td>\n",
       "      <td>Hi its in durban are you still on this number</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5546</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ic. There are a lotta childporn cars then.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5547</th>\n",
       "      <td>spam</td>\n",
       "      <td>Had your contract mobile 11 Mnths? Latest Moto...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5548</th>\n",
       "      <td>ham</td>\n",
       "      <td>No, I was trying it all weekend ;V</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5549</th>\n",
       "      <td>ham</td>\n",
       "      <td>You know, wot people wear. T shirts, jumpers, ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5550</th>\n",
       "      <td>ham</td>\n",
       "      <td>Cool, what time you think you can get here?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5551</th>\n",
       "      <td>ham</td>\n",
       "      <td>Wen did you get so spiritual and deep. That's ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5552</th>\n",
       "      <td>ham</td>\n",
       "      <td>Have a safe trip to Nigeria. Wish you happines...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5553</th>\n",
       "      <td>ham</td>\n",
       "      <td>Hahaha..use your brain dear</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5554</th>\n",
       "      <td>ham</td>\n",
       "      <td>Well keep in mind I've only got enough gas for...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5555</th>\n",
       "      <td>ham</td>\n",
       "      <td>Yeh. Indians was nice. Tho it did kane me off ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5556</th>\n",
       "      <td>ham</td>\n",
       "      <td>Yes i have. So that's why u texted. Pshew...mi...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5557</th>\n",
       "      <td>ham</td>\n",
       "      <td>No. I meant the calculation is the same. That ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5558</th>\n",
       "      <td>ham</td>\n",
       "      <td>Sorry, I'll call later</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5559</th>\n",
       "      <td>ham</td>\n",
       "      <td>if you aren't here in the next  &amp;lt;#&amp;gt;  hou...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5560</th>\n",
       "      <td>ham</td>\n",
       "      <td>Anything lor. Juz both of us lor.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5561</th>\n",
       "      <td>ham</td>\n",
       "      <td>Get me out of this dump heap. My mom decided t...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5562</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ok lor... Sony ericsson salesman... I ask shuh...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5563</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ard 6 like dat lor.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5564</th>\n",
       "      <td>ham</td>\n",
       "      <td>Why don't you wait 'til at least wednesday to ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5565</th>\n",
       "      <td>ham</td>\n",
       "      <td>Huh y lei...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5566</th>\n",
       "      <td>spam</td>\n",
       "      <td>REMINDER FROM O2: To get 2.50 pounds free call...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5567</th>\n",
       "      <td>spam</td>\n",
       "      <td>This is the 2nd time we have tried 2 contact u...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5568</th>\n",
       "      <td>ham</td>\n",
       "      <td>Will ü b going to esplanade fr home?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5569</th>\n",
       "      <td>ham</td>\n",
       "      <td>Pity, * was in mood for that. So...any other s...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5570</th>\n",
       "      <td>ham</td>\n",
       "      <td>The guy did some bitching but I acted like i'd...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5571</th>\n",
       "      <td>ham</td>\n",
       "      <td>Rofl. Its true to its name</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>5572 rows × 2 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>label</th>\n",
       "      <th>msg</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>ham</td>\n",
       "      <td>Go until jurong point, crazy.. Available only ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ok lar... Joking wif u oni...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>spam</td>\n",
       "      <td>Free entry in 2 a wkly comp to win FA Cup fina...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>ham</td>\n",
       "      <td>U dun say so early hor... U c already then say...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>ham</td>\n",
       "      <td>Nah I don't think he goes to usf, he lives aro...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>spam</td>\n",
       "      <td>FreeMsg Hey there darling it's been 3 week's n...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>ham</td>\n",
       "      <td>Even my brother is not like to speak with me. ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>ham</td>\n",
       "      <td>As per your request 'Melle Melle (Oru Minnamin...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>spam</td>\n",
       "      <td>WINNER!! As a valued network customer you have...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>spam</td>\n",
       "      <td>Had your mobile 11 months or more? U R entitle...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>ham</td>\n",
       "      <td>I'm gonna be home soon and i don't want to tal...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>spam</td>\n",
       "      <td>SIX chances to win CASH! From 100 to 20,000 po...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>spam</td>\n",
       "      <td>URGENT! You have won a 1 week FREE membership ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>ham</td>\n",
       "      <td>I've been searching for the right words to tha...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>ham</td>\n",
       "      <td>I HAVE A DATE ON SUNDAY WITH WILL!!</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>spam</td>\n",
       "      <td>XXXMobileMovieClub: To use your credit, click ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>ham</td>\n",
       "      <td>Oh k...i'm watching here:)</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>ham</td>\n",
       "      <td>Eh u remember how 2 spell his name... Yes i di...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>ham</td>\n",
       "      <td>Fine if thats the way u feel. Thats the way ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>spam</td>\n",
       "      <td>England v Macedonia - dont miss the goals/team...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>ham</td>\n",
       "      <td>Is that seriously how you spell his name?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>ham</td>\n",
       "      <td>I‘m going to try for 2 months ha ha only joking</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>ham</td>\n",
       "      <td>So ü pay first lar... Then when is da stock co...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>ham</td>\n",
       "      <td>Aft i finish my lunch then i go str down lor. ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ffffffffff. Alright no way I can meet up with ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>ham</td>\n",
       "      <td>Just forced myself to eat a slice. I'm really ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>ham</td>\n",
       "      <td>Lol your always so convincing.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>ham</td>\n",
       "      <td>Did you catch the bus ? Are you frying an egg ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>ham</td>\n",
       "      <td>I'm back &amp;amp; we're packing the car now, I'll...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ahhh. Work. I vaguely remember that! What does...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5542</th>\n",
       "      <td>ham</td>\n",
       "      <td>Armand says get your ass over to epsilon</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5543</th>\n",
       "      <td>ham</td>\n",
       "      <td>U still havent got urself a jacket ah?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5544</th>\n",
       "      <td>ham</td>\n",
       "      <td>I'm taking derek &amp;amp; taylor to walmart, if I...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5545</th>\n",
       "      <td>ham</td>\n",
       "      <td>Hi its in durban are you still on this number</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5546</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ic. There are a lotta childporn cars then.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5547</th>\n",
       "      <td>spam</td>\n",
       "      <td>Had your contract mobile 11 Mnths? Latest Moto...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5548</th>\n",
       "      <td>ham</td>\n",
       "      <td>No, I was trying it all weekend ;V</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5549</th>\n",
       "      <td>ham</td>\n",
       "      <td>You know, wot people wear. T shirts, jumpers, ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5550</th>\n",
       "      <td>ham</td>\n",
       "      <td>Cool, what time you think you can get here?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5551</th>\n",
       "      <td>ham</td>\n",
       "      <td>Wen did you get so spiritual and deep. That's ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5552</th>\n",
       "      <td>ham</td>\n",
       "      <td>Have a safe trip to Nigeria. Wish you happines...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5553</th>\n",
       "      <td>ham</td>\n",
       "      <td>Hahaha..use your brain dear</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5554</th>\n",
       "      <td>ham</td>\n",
       "      <td>Well keep in mind I've only got enough gas for...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5555</th>\n",
       "      <td>ham</td>\n",
       "      <td>Yeh. Indians was nice. Tho it did kane me off ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5556</th>\n",
       "      <td>ham</td>\n",
       "      <td>Yes i have. So that's why u texted. Pshew...mi...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5557</th>\n",
       "      <td>ham</td>\n",
       "      <td>No. I meant the calculation is the same. That ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5558</th>\n",
       "      <td>ham</td>\n",
       "      <td>Sorry, I'll call later</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5559</th>\n",
       "      <td>ham</td>\n",
       "      <td>if you aren't here in the next  &amp;lt;#&amp;gt;  hou...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5560</th>\n",
       "      <td>ham</td>\n",
       "      <td>Anything lor. Juz both of us lor.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5561</th>\n",
       "      <td>ham</td>\n",
       "      <td>Get me out of this dump heap. My mom decided t...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5562</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ok lor... Sony ericsson salesman... I ask shuh...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5563</th>\n",
       "      <td>ham</td>\n",
       "      <td>Ard 6 like dat lor.</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5564</th>\n",
       "      <td>ham</td>\n",
       "      <td>Why don't you wait 'til at least wednesday to ...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5565</th>\n",
       "      <td>ham</td>\n",
       "      <td>Huh y lei...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5566</th>\n",
       "      <td>spam</td>\n",
       "      <td>REMINDER FROM O2: To get 2.50 pounds free call...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5567</th>\n",
       "      <td>spam</td>\n",
       "      <td>This is the 2nd time we have tried 2 contact u...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5568</th>\n",
       "      <td>ham</td>\n",
       "      <td>Will ü b going to esplanade fr home?</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5569</th>\n",
       "      <td>ham</td>\n",
       "      <td>Pity, * was in mood for that. So...any other s...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5570</th>\n",
       "      <td>ham</td>\n",
       "      <td>The guy did some bitching but I acted like i'd...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5571</th>\n",
       "      <td>ham</td>\n",
       "      <td>Rofl. Its true to its name</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>5572 rows × 2 columns</p>\n",
       "</div>"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df = pd.read_table('https://raw.githubusercontent.com/sinanuozdemir/sfdat22/master/data/sms.tsv', sep='\\t', header=None, names=['label', 'msg'])\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "ham     4825\nspam     747\nName: label, dtype: int64"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.label.value_counts()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "spam probability: 0.13406317300789664, ham probability: 0.8659368269921034\n"
     ]
    }
   ],
   "source": [
    "value_probablity = df.label.value_counts()/len(df)\n",
    "spam_probability = value_probablity.spam\n",
    "ham_probability = value_probablity.ham\n",
    "print('spam probability: {}, ham probability: {}'.format(spam_probability, ham_probability))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "word send probability: 0.06693440428380187\nword cash probability: 0.06827309236947791\nword now probability: 0.1994645247657296\nspam words probability: 0.00012220082487226017\n"
     ]
    }
   ],
   "source": [
    "spams = df[df.label == 'spam']\n",
    "sentence = 'send cash now'\n",
    "spam_words_probability = 1\n",
    "for word in sentence.split():\n",
    "    word_probability = spams[spams.msg.str.contains(word)].shape[0]/float(spams.shape[0])\n",
    "    print(\"word {} probability: {}\".format(word, word_probability))\n",
    "    spam_words_probability *= word_probability\n",
    "spam_words_probability *= spam_probability\n",
    "print('spam words probability: {}'.format(spam_words_probability))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "word send probability: 0.023626943005181346\nword cash probability: 0.002694300518134715\nword now probability: 0.10051813471502591\nham words probability: 5.540949590575691e-06\n"
     ]
    }
   ],
   "source": [
    "hams = df[df.label == 'ham']\n",
    "sentence = 'send cash now'\n",
    "ham_words_probability = 1\n",
    "for word in sentence.split():\n",
    "    word_probability = hams[hams.msg.str.contains(word)].shape[0]/float(hams.shape[0])\n",
    "    print(\"word {} probability: {}\".format(word, word_probability))\n",
    "    ham_words_probability *= word_probability\n",
    "ham_words_probability *= ham_probability\n",
    "print('ham words probability: {}'.format(ham_words_probability))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "send cash now is more likely a spam\n"
     ]
    }
   ],
   "source": [
    "if spam_words_probability > ham_words_probability:\n",
    "    print('{} is more likely a spam'.format(sentence))\n",
    "else:\n",
    "    print('{} is more likely NOT a spam'.format(sentence))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Use the built-in library methods"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array(['ham', 'ham', 'ham', ..., 'ham', 'spam', 'ham'], \n      dtype='<U4')"
      ]
     },
     "execution_count": 31,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "from sklearn.model_selection import train_test_split\n",
    "from sklearn.feature_extraction.text import CountVectorizer\n",
    "from sklearn.naive_bayes import MultinomialNB\n",
    "x_train, x_test, y_train, y_test = train_test_split(df.msg, df.label, random_state=1)\n",
    "vect = CountVectorizer()\n",
    "train_dtm = vect.fit_transform(x_train)\n",
    "test_dtm = vect.transform(x_test)\n",
    "nb = MultinomialNB()\n",
    "nb.fit(train_dtm, y_train)\n",
    "predicts = nb.predict(test_dtm)\n",
    "predicts"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "accuracy: 0.9885139985642498, confusion matrix: [[1203    5]\n [  11  174]]\n"
     ]
    }
   ],
   "source": [
    "from sklearn import metrics\n",
    "print('accuracy: {}, confusion matrix: {}'\n",
    "      .format(metrics.accuracy_score(y_test, predicts), metrics.confusion_matrix(y_test, predicts)))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "for confusion matrix, see: http://scikit-learn.org/stable/modules/generated/sklearn.metrics.confusion_matrix.html"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    ""
   ]
  }
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