diff --git a/your-code/main.ipynb b/your-code/main.ipynb
index 7900997..6976535 100644
--- a/your-code/main.ipynb
+++ b/your-code/main.ipynb
@@ -1,169 +1,1666 @@
-{
- "cells": [
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 1. Import pandas library"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 2. Import users table:"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 3. Rename Id column to userId"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 4. Import posts table:"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 5. Rename Id column to postId and OwnerUserId to userId"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 6. Define new dataframes for users and posts with the following selected columns:\n",
-    "    **users columns**: userId, Reputation,Views,UpVotes,DownVotes\n",
-    "    **posts columns**: postId, Score,userId,ViewCount,CommentCount"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 7. Merge both dataframes, users and posts. \n",
-    "You will need to make a [merge](https://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.merge.html) of posts and users dataframes."
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 8. How many missing values do you have in your merged dataframe? On which columns?"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 9. You will need to make something with missing values.  Will you clean or filling them? Explain. \n",
-    "**Remember** to check the results of your code before passing to the next step"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "#### 10. Adjust the data types in order to avoid future issues. Which ones should be changed? "
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  }
- ],
- "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": "3.6.8"
-  }
- },
- "nbformat": 4,
- "nbformat_minor": 2
-}
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 1. Import pandas library"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import pandas as pd "
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 2. Import users table:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "users_raw = pd.read_csv('users_table.csv')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "scrolled": true
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>Id</th>\n",
+       "      <th>Reputation</th>\n",
+       "      <th>CreationDate</th>\n",
+       "      <th>DisplayName</th>\n",
+       "      <th>LastAccessDate</th>\n",
+       "      <th>WebsiteUrl</th>\n",
+       "      <th>Location</th>\n",
+       "      <th>AboutMe</th>\n",
+       "      <th>Views</th>\n",
+       "      <th>UpVotes</th>\n",
+       "      <th>DownVotes</th>\n",
+       "      <th>AccountId</th>\n",
+       "      <th>Age</th>\n",
+       "      <th>ProfileImageUrl</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>2010-07-19 06:55:26</td>\n",
+       "      <td>Community</td>\n",
+       "      <td>2010-07-19 06:55:26</td>\n",
+       "      <td>http://meta.stackexchange.com/</td>\n",
+       "      <td>on the server farm</td>\n",
+       "      <td>&lt;p&gt;Hi, I'm not really a person.&lt;/p&gt;\\r\\n\\r\\n&lt;p&gt;...</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>-1</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>101</td>\n",
+       "      <td>2010-07-19 14:01:36</td>\n",
+       "      <td>Geoff Dalgas</td>\n",
+       "      <td>2013-11-12 22:07:23</td>\n",
+       "      <td>http://stackoverflow.com</td>\n",
+       "      <td>Corvallis, OR</td>\n",
+       "      <td>&lt;p&gt;Developer on the StackOverflow team.  Find ...</td>\n",
+       "      <td>25</td>\n",
+       "      <td>3</td>\n",
+       "      <td>0</td>\n",
+       "      <td>2</td>\n",
+       "      <td>37.0</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>101</td>\n",
+       "      <td>2010-07-19 15:34:50</td>\n",
+       "      <td>Jarrod Dixon</td>\n",
+       "      <td>2014-08-08 06:42:58</td>\n",
+       "      <td>http://stackoverflow.com</td>\n",
+       "      <td>New York, NY</td>\n",
+       "      <td>&lt;p&gt;&lt;a href=\"http://blog.stackoverflow.com/2009...</td>\n",
+       "      <td>22</td>\n",
+       "      <td>19</td>\n",
+       "      <td>0</td>\n",
+       "      <td>3</td>\n",
+       "      <td>35.0</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>101</td>\n",
+       "      <td>2010-07-19 19:03:27</td>\n",
+       "      <td>Emmett</td>\n",
+       "      <td>2014-01-02 09:31:02</td>\n",
+       "      <td>http://minesweeperonline.com</td>\n",
+       "      <td>San Francisco, CA</td>\n",
+       "      <td>&lt;p&gt;currently at a startup in SF&lt;/p&gt;\\r\\n\\r\\n&lt;p&gt;...</td>\n",
+       "      <td>11</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0</td>\n",
+       "      <td>1998</td>\n",
+       "      <td>28.0</td>\n",
+       "      <td>http://i.stack.imgur.com/d1oHX.jpg</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>2010-07-19 19:03:57</td>\n",
+       "      <td>Shane</td>\n",
+       "      <td>2014-08-13 00:23:47</td>\n",
+       "      <td>http://www.statalgo.com</td>\n",
+       "      <td>New York, NY</td>\n",
+       "      <td>&lt;p&gt;Quantitative researcher focusing on statist...</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>54503</td>\n",
+       "      <td>35.0</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   Id  Reputation         CreationDate   DisplayName       LastAccessDate  \\\n",
+       "0  -1           1  2010-07-19 06:55:26     Community  2010-07-19 06:55:26   \n",
+       "1   2         101  2010-07-19 14:01:36  Geoff Dalgas  2013-11-12 22:07:23   \n",
+       "2   3         101  2010-07-19 15:34:50  Jarrod Dixon  2014-08-08 06:42:58   \n",
+       "3   4         101  2010-07-19 19:03:27        Emmett  2014-01-02 09:31:02   \n",
+       "4   5        6792  2010-07-19 19:03:57         Shane  2014-08-13 00:23:47   \n",
+       "\n",
+       "                       WebsiteUrl            Location  \\\n",
+       "0  http://meta.stackexchange.com/  on the server farm   \n",
+       "1        http://stackoverflow.com       Corvallis, OR   \n",
+       "2        http://stackoverflow.com        New York, NY   \n",
+       "3    http://minesweeperonline.com   San Francisco, CA   \n",
+       "4         http://www.statalgo.com        New York, NY   \n",
+       "\n",
+       "                                             AboutMe  Views  UpVotes  \\\n",
+       "0  <p>Hi, I'm not really a person.</p>\\r\\n\\r\\n<p>...      0     5007   \n",
+       "1  <p>Developer on the StackOverflow team.  Find ...     25        3   \n",
+       "2  <p><a href=\"http://blog.stackoverflow.com/2009...     22       19   \n",
+       "3  <p>currently at a startup in SF</p>\\r\\n\\r\\n<p>...     11        0   \n",
+       "4  <p>Quantitative researcher focusing on statist...   1145      662   \n",
+       "\n",
+       "   DownVotes  AccountId   Age                     ProfileImageUrl  \n",
+       "0       1920         -1   NaN                                 NaN  \n",
+       "1          0          2  37.0                                 NaN  \n",
+       "2          0          3  35.0                                 NaN  \n",
+       "3          0       1998  28.0  http://i.stack.imgur.com/d1oHX.jpg  \n",
+       "4          5      54503  35.0                                 NaN  "
+      ]
+     },
+     "execution_count": 3,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "users_raw.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 3. Rename Id column to userId"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>userId</th>\n",
+       "      <th>Reputation</th>\n",
+       "      <th>CreationDate</th>\n",
+       "      <th>DisplayName</th>\n",
+       "      <th>LastAccessDate</th>\n",
+       "      <th>WebsiteUrl</th>\n",
+       "      <th>Location</th>\n",
+       "      <th>AboutMe</th>\n",
+       "      <th>Views</th>\n",
+       "      <th>UpVotes</th>\n",
+       "      <th>DownVotes</th>\n",
+       "      <th>AccountId</th>\n",
+       "      <th>Age</th>\n",
+       "      <th>ProfileImageUrl</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>2010-07-19 06:55:26</td>\n",
+       "      <td>Community</td>\n",
+       "      <td>2010-07-19 06:55:26</td>\n",
+       "      <td>http://meta.stackexchange.com/</td>\n",
+       "      <td>on the server farm</td>\n",
+       "      <td>&lt;p&gt;Hi, I'm not really a person.&lt;/p&gt;\\r\\n\\r\\n&lt;p&gt;...</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>-1</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>101</td>\n",
+       "      <td>2010-07-19 14:01:36</td>\n",
+       "      <td>Geoff Dalgas</td>\n",
+       "      <td>2013-11-12 22:07:23</td>\n",
+       "      <td>http://stackoverflow.com</td>\n",
+       "      <td>Corvallis, OR</td>\n",
+       "      <td>&lt;p&gt;Developer on the StackOverflow team.  Find ...</td>\n",
+       "      <td>25</td>\n",
+       "      <td>3</td>\n",
+       "      <td>0</td>\n",
+       "      <td>2</td>\n",
+       "      <td>37.0</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>101</td>\n",
+       "      <td>2010-07-19 15:34:50</td>\n",
+       "      <td>Jarrod Dixon</td>\n",
+       "      <td>2014-08-08 06:42:58</td>\n",
+       "      <td>http://stackoverflow.com</td>\n",
+       "      <td>New York, NY</td>\n",
+       "      <td>&lt;p&gt;&lt;a href=\"http://blog.stackoverflow.com/2009...</td>\n",
+       "      <td>22</td>\n",
+       "      <td>19</td>\n",
+       "      <td>0</td>\n",
+       "      <td>3</td>\n",
+       "      <td>35.0</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>101</td>\n",
+       "      <td>2010-07-19 19:03:27</td>\n",
+       "      <td>Emmett</td>\n",
+       "      <td>2014-01-02 09:31:02</td>\n",
+       "      <td>http://minesweeperonline.com</td>\n",
+       "      <td>San Francisco, CA</td>\n",
+       "      <td>&lt;p&gt;currently at a startup in SF&lt;/p&gt;\\r\\n\\r\\n&lt;p&gt;...</td>\n",
+       "      <td>11</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0</td>\n",
+       "      <td>1998</td>\n",
+       "      <td>28.0</td>\n",
+       "      <td>http://i.stack.imgur.com/d1oHX.jpg</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>2010-07-19 19:03:57</td>\n",
+       "      <td>Shane</td>\n",
+       "      <td>2014-08-13 00:23:47</td>\n",
+       "      <td>http://www.statalgo.com</td>\n",
+       "      <td>New York, NY</td>\n",
+       "      <td>&lt;p&gt;Quantitative researcher focusing on statist...</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>54503</td>\n",
+       "      <td>35.0</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   userId  Reputation         CreationDate   DisplayName       LastAccessDate  \\\n",
+       "0      -1           1  2010-07-19 06:55:26     Community  2010-07-19 06:55:26   \n",
+       "1       2         101  2010-07-19 14:01:36  Geoff Dalgas  2013-11-12 22:07:23   \n",
+       "2       3         101  2010-07-19 15:34:50  Jarrod Dixon  2014-08-08 06:42:58   \n",
+       "3       4         101  2010-07-19 19:03:27        Emmett  2014-01-02 09:31:02   \n",
+       "4       5        6792  2010-07-19 19:03:57         Shane  2014-08-13 00:23:47   \n",
+       "\n",
+       "                       WebsiteUrl            Location  \\\n",
+       "0  http://meta.stackexchange.com/  on the server farm   \n",
+       "1        http://stackoverflow.com       Corvallis, OR   \n",
+       "2        http://stackoverflow.com        New York, NY   \n",
+       "3    http://minesweeperonline.com   San Francisco, CA   \n",
+       "4         http://www.statalgo.com        New York, NY   \n",
+       "\n",
+       "                                             AboutMe  Views  UpVotes  \\\n",
+       "0  <p>Hi, I'm not really a person.</p>\\r\\n\\r\\n<p>...      0     5007   \n",
+       "1  <p>Developer on the StackOverflow team.  Find ...     25        3   \n",
+       "2  <p><a href=\"http://blog.stackoverflow.com/2009...     22       19   \n",
+       "3  <p>currently at a startup in SF</p>\\r\\n\\r\\n<p>...     11        0   \n",
+       "4  <p>Quantitative researcher focusing on statist...   1145      662   \n",
+       "\n",
+       "   DownVotes  AccountId   Age                     ProfileImageUrl  \n",
+       "0       1920         -1   NaN                                 NaN  \n",
+       "1          0          2  37.0                                 NaN  \n",
+       "2          0          3  35.0                                 NaN  \n",
+       "3          0       1998  28.0  http://i.stack.imgur.com/d1oHX.jpg  \n",
+       "4          5      54503  35.0                                 NaN  "
+      ]
+     },
+     "execution_count": 6,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "users_raw.rename(columns={'Id':'userId'},inplace=True)\n",
+    "users_raw.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 4. Import posts table:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>Id</th>\n",
+       "      <th>PostTypeId</th>\n",
+       "      <th>AcceptedAnswerId</th>\n",
+       "      <th>CreaionDate</th>\n",
+       "      <th>Score</th>\n",
+       "      <th>ViewCount</th>\n",
+       "      <th>Body</th>\n",
+       "      <th>OwnerUserId</th>\n",
+       "      <th>LasActivityDate</th>\n",
+       "      <th>Title</th>\n",
+       "      <th>...</th>\n",
+       "      <th>AnswerCount</th>\n",
+       "      <th>CommentCount</th>\n",
+       "      <th>FavoriteCount</th>\n",
+       "      <th>LastEditorUserId</th>\n",
+       "      <th>LastEditDate</th>\n",
+       "      <th>CommunityOwnedDate</th>\n",
+       "      <th>ParentId</th>\n",
+       "      <th>ClosedDate</th>\n",
+       "      <th>OwnerDisplayName</th>\n",
+       "      <th>LastEditorDisplayName</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>15.0</td>\n",
+       "      <td>2010-07-19 19:12:12</td>\n",
+       "      <td>23</td>\n",
+       "      <td>1278.0</td>\n",
+       "      <td>&lt;p&gt;How should I elicit prior distributions fro...</td>\n",
+       "      <td>8.0</td>\n",
+       "      <td>2010-09-15 21:08:26</td>\n",
+       "      <td>Eliciting priors from experts</td>\n",
+       "      <td>...</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>1</td>\n",
+       "      <td>14.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>1</td>\n",
+       "      <td>59.0</td>\n",
+       "      <td>2010-07-19 19:12:57</td>\n",
+       "      <td>22</td>\n",
+       "      <td>8198.0</td>\n",
+       "      <td>&lt;p&gt;In many different statistical methods there...</td>\n",
+       "      <td>24.0</td>\n",
+       "      <td>2012-11-12 09:21:54</td>\n",
+       "      <td>What is normality?</td>\n",
+       "      <td>...</td>\n",
+       "      <td>7.0</td>\n",
+       "      <td>1</td>\n",
+       "      <td>8.0</td>\n",
+       "      <td>88.0</td>\n",
+       "      <td>2010-08-07 17:56:44</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>1</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>2010-07-19 19:13:28</td>\n",
+       "      <td>54</td>\n",
+       "      <td>3613.0</td>\n",
+       "      <td>&lt;p&gt;What are some valuable Statistical Analysis...</td>\n",
+       "      <td>18.0</td>\n",
+       "      <td>2013-05-27 14:48:36</td>\n",
+       "      <td>What are some valuable Statistical Analysis op...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>19.0</td>\n",
+       "      <td>4</td>\n",
+       "      <td>36.0</td>\n",
+       "      <td>183.0</td>\n",
+       "      <td>2011-02-12 05:50:03</td>\n",
+       "      <td>2010-07-19 19:13:28</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>1</td>\n",
+       "      <td>135.0</td>\n",
+       "      <td>2010-07-19 19:13:31</td>\n",
+       "      <td>13</td>\n",
+       "      <td>5224.0</td>\n",
+       "      <td>&lt;p&gt;I have two groups of data.  Each with a dif...</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>2010-09-08 03:00:19</td>\n",
+       "      <td>Assessing the significance of differences in d...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>2</td>\n",
+       "      <td>2.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>2</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>2010-07-19 19:14:43</td>\n",
+       "      <td>81</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>&lt;p&gt;The R-project&lt;/p&gt;\\n\\n&lt;p&gt;&lt;a href=\"http://www...</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>2010-07-19 19:21:15</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>...</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>3</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>2010-07-19 19:21:15</td>\n",
+       "      <td>2010-07-19 19:14:43</td>\n",
+       "      <td>3.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "<p>5 rows × 21 columns</p>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   Id  PostTypeId  AcceptedAnswerId          CreaionDate  Score  ViewCount  \\\n",
+       "0   1           1              15.0  2010-07-19 19:12:12     23     1278.0   \n",
+       "1   2           1              59.0  2010-07-19 19:12:57     22     8198.0   \n",
+       "2   3           1               5.0  2010-07-19 19:13:28     54     3613.0   \n",
+       "3   4           1             135.0  2010-07-19 19:13:31     13     5224.0   \n",
+       "4   5           2               NaN  2010-07-19 19:14:43     81        NaN   \n",
+       "\n",
+       "                                                Body  OwnerUserId  \\\n",
+       "0  <p>How should I elicit prior distributions fro...          8.0   \n",
+       "1  <p>In many different statistical methods there...         24.0   \n",
+       "2  <p>What are some valuable Statistical Analysis...         18.0   \n",
+       "3  <p>I have two groups of data.  Each with a dif...         23.0   \n",
+       "4  <p>The R-project</p>\\n\\n<p><a href=\"http://www...         23.0   \n",
+       "\n",
+       "       LasActivityDate                                              Title  \\\n",
+       "0  2010-09-15 21:08:26                      Eliciting priors from experts   \n",
+       "1  2012-11-12 09:21:54                                 What is normality?   \n",
+       "2  2013-05-27 14:48:36  What are some valuable Statistical Analysis op...   \n",
+       "3  2010-09-08 03:00:19  Assessing the significance of differences in d...   \n",
+       "4  2010-07-19 19:21:15                                                NaN   \n",
+       "\n",
+       "   ... AnswerCount  CommentCount  FavoriteCount  LastEditorUserId  \\\n",
+       "0  ...         5.0             1           14.0               NaN   \n",
+       "1  ...         7.0             1            8.0              88.0   \n",
+       "2  ...        19.0             4           36.0             183.0   \n",
+       "3  ...         5.0             2            2.0               NaN   \n",
+       "4  ...         NaN             3            NaN              23.0   \n",
+       "\n",
+       "          LastEditDate   CommunityOwnedDate ParentId  ClosedDate  \\\n",
+       "0                  NaN                  NaN      NaN         NaN   \n",
+       "1  2010-08-07 17:56:44                  NaN      NaN         NaN   \n",
+       "2  2011-02-12 05:50:03  2010-07-19 19:13:28      NaN         NaN   \n",
+       "3                  NaN                  NaN      NaN         NaN   \n",
+       "4  2010-07-19 19:21:15  2010-07-19 19:14:43      3.0         NaN   \n",
+       "\n",
+       "  OwnerDisplayName LastEditorDisplayName  \n",
+       "0              NaN                   NaN  \n",
+       "1              NaN                   NaN  \n",
+       "2              NaN                   NaN  \n",
+       "3              NaN                   NaN  \n",
+       "4              NaN                   NaN  \n",
+       "\n",
+       "[5 rows x 21 columns]"
+      ]
+     },
+     "execution_count": 7,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "posts_raw=pd.read_csv('posts_table.csv')\n",
+    "posts_raw.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 5. Rename Id column to postId and OwnerUserId to userId"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>postId</th>\n",
+       "      <th>PostTypeId</th>\n",
+       "      <th>AcceptedAnswerId</th>\n",
+       "      <th>CreaionDate</th>\n",
+       "      <th>Score</th>\n",
+       "      <th>ViewCount</th>\n",
+       "      <th>Body</th>\n",
+       "      <th>userId</th>\n",
+       "      <th>LasActivityDate</th>\n",
+       "      <th>Title</th>\n",
+       "      <th>...</th>\n",
+       "      <th>AnswerCount</th>\n",
+       "      <th>CommentCount</th>\n",
+       "      <th>FavoriteCount</th>\n",
+       "      <th>LastEditorUserId</th>\n",
+       "      <th>LastEditDate</th>\n",
+       "      <th>CommunityOwnedDate</th>\n",
+       "      <th>ParentId</th>\n",
+       "      <th>ClosedDate</th>\n",
+       "      <th>OwnerDisplayName</th>\n",
+       "      <th>LastEditorDisplayName</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>15.0</td>\n",
+       "      <td>2010-07-19 19:12:12</td>\n",
+       "      <td>23</td>\n",
+       "      <td>1278.0</td>\n",
+       "      <td>&lt;p&gt;How should I elicit prior distributions fro...</td>\n",
+       "      <td>8.0</td>\n",
+       "      <td>2010-09-15 21:08:26</td>\n",
+       "      <td>Eliciting priors from experts</td>\n",
+       "      <td>...</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>1</td>\n",
+       "      <td>14.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>1</td>\n",
+       "      <td>59.0</td>\n",
+       "      <td>2010-07-19 19:12:57</td>\n",
+       "      <td>22</td>\n",
+       "      <td>8198.0</td>\n",
+       "      <td>&lt;p&gt;In many different statistical methods there...</td>\n",
+       "      <td>24.0</td>\n",
+       "      <td>2012-11-12 09:21:54</td>\n",
+       "      <td>What is normality?</td>\n",
+       "      <td>...</td>\n",
+       "      <td>7.0</td>\n",
+       "      <td>1</td>\n",
+       "      <td>8.0</td>\n",
+       "      <td>88.0</td>\n",
+       "      <td>2010-08-07 17:56:44</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>1</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>2010-07-19 19:13:28</td>\n",
+       "      <td>54</td>\n",
+       "      <td>3613.0</td>\n",
+       "      <td>&lt;p&gt;What are some valuable Statistical Analysis...</td>\n",
+       "      <td>18.0</td>\n",
+       "      <td>2013-05-27 14:48:36</td>\n",
+       "      <td>What are some valuable Statistical Analysis op...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>19.0</td>\n",
+       "      <td>4</td>\n",
+       "      <td>36.0</td>\n",
+       "      <td>183.0</td>\n",
+       "      <td>2011-02-12 05:50:03</td>\n",
+       "      <td>2010-07-19 19:13:28</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>1</td>\n",
+       "      <td>135.0</td>\n",
+       "      <td>2010-07-19 19:13:31</td>\n",
+       "      <td>13</td>\n",
+       "      <td>5224.0</td>\n",
+       "      <td>&lt;p&gt;I have two groups of data.  Each with a dif...</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>2010-09-08 03:00:19</td>\n",
+       "      <td>Assessing the significance of differences in d...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>2</td>\n",
+       "      <td>2.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>2</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>2010-07-19 19:14:43</td>\n",
+       "      <td>81</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>&lt;p&gt;The R-project&lt;/p&gt;\\n\\n&lt;p&gt;&lt;a href=\"http://www...</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>2010-07-19 19:21:15</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>...</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>3</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>2010-07-19 19:21:15</td>\n",
+       "      <td>2010-07-19 19:14:43</td>\n",
+       "      <td>3.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>NaN</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "<p>5 rows × 21 columns</p>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   postId  PostTypeId  AcceptedAnswerId          CreaionDate  Score  \\\n",
+       "0       1           1              15.0  2010-07-19 19:12:12     23   \n",
+       "1       2           1              59.0  2010-07-19 19:12:57     22   \n",
+       "2       3           1               5.0  2010-07-19 19:13:28     54   \n",
+       "3       4           1             135.0  2010-07-19 19:13:31     13   \n",
+       "4       5           2               NaN  2010-07-19 19:14:43     81   \n",
+       "\n",
+       "   ViewCount                                               Body  userId  \\\n",
+       "0     1278.0  <p>How should I elicit prior distributions fro...     8.0   \n",
+       "1     8198.0  <p>In many different statistical methods there...    24.0   \n",
+       "2     3613.0  <p>What are some valuable Statistical Analysis...    18.0   \n",
+       "3     5224.0  <p>I have two groups of data.  Each with a dif...    23.0   \n",
+       "4        NaN  <p>The R-project</p>\\n\\n<p><a href=\"http://www...    23.0   \n",
+       "\n",
+       "       LasActivityDate                                              Title  \\\n",
+       "0  2010-09-15 21:08:26                      Eliciting priors from experts   \n",
+       "1  2012-11-12 09:21:54                                 What is normality?   \n",
+       "2  2013-05-27 14:48:36  What are some valuable Statistical Analysis op...   \n",
+       "3  2010-09-08 03:00:19  Assessing the significance of differences in d...   \n",
+       "4  2010-07-19 19:21:15                                                NaN   \n",
+       "\n",
+       "   ... AnswerCount  CommentCount  FavoriteCount  LastEditorUserId  \\\n",
+       "0  ...         5.0             1           14.0               NaN   \n",
+       "1  ...         7.0             1            8.0              88.0   \n",
+       "2  ...        19.0             4           36.0             183.0   \n",
+       "3  ...         5.0             2            2.0               NaN   \n",
+       "4  ...         NaN             3            NaN              23.0   \n",
+       "\n",
+       "          LastEditDate   CommunityOwnedDate ParentId  ClosedDate  \\\n",
+       "0                  NaN                  NaN      NaN         NaN   \n",
+       "1  2010-08-07 17:56:44                  NaN      NaN         NaN   \n",
+       "2  2011-02-12 05:50:03  2010-07-19 19:13:28      NaN         NaN   \n",
+       "3                  NaN                  NaN      NaN         NaN   \n",
+       "4  2010-07-19 19:21:15  2010-07-19 19:14:43      3.0         NaN   \n",
+       "\n",
+       "  OwnerDisplayName LastEditorDisplayName  \n",
+       "0              NaN                   NaN  \n",
+       "1              NaN                   NaN  \n",
+       "2              NaN                   NaN  \n",
+       "3              NaN                   NaN  \n",
+       "4              NaN                   NaN  \n",
+       "\n",
+       "[5 rows x 21 columns]"
+      ]
+     },
+     "execution_count": 11,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "posts_raw.rename(columns={'Id':'postId','OwnerUserId':'userId'},inplace=True)\n",
+    "posts_raw.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 6. Define new dataframes for users and posts with the following selected columns:\n",
+    "    **users columns**: userId, Reputation,Views,UpVotes,DownVotes\n",
+    "    **posts columns**: postId, Score,userId,ViewCount,CommentCount"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>userId</th>\n",
+       "      <th>Reputation</th>\n",
+       "      <th>Views</th>\n",
+       "      <th>UpVotes</th>\n",
+       "      <th>DownVotes</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>101</td>\n",
+       "      <td>25</td>\n",
+       "      <td>3</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>101</td>\n",
+       "      <td>22</td>\n",
+       "      <td>19</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>101</td>\n",
+       "      <td>11</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   userId  Reputation  Views  UpVotes  DownVotes\n",
+       "0      -1           1      0     5007       1920\n",
+       "1       2         101     25        3          0\n",
+       "2       3         101     22       19          0\n",
+       "3       4         101     11        0          0\n",
+       "4       5        6792   1145      662          5"
+      ]
+     },
+     "execution_count": 9,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "users = users_raw[['userId','Reputation','Views','UpVotes','DownVotes']]\n",
+    "users.head()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>postId</th>\n",
+       "      <th>Score</th>\n",
+       "      <th>userId</th>\n",
+       "      <th>ViewCount</th>\n",
+       "      <th>CommentCount</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>1</td>\n",
+       "      <td>23</td>\n",
+       "      <td>8.0</td>\n",
+       "      <td>1278.0</td>\n",
+       "      <td>1</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>22</td>\n",
+       "      <td>24.0</td>\n",
+       "      <td>8198.0</td>\n",
+       "      <td>1</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>54</td>\n",
+       "      <td>18.0</td>\n",
+       "      <td>3613.0</td>\n",
+       "      <td>4</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>13</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>5224.0</td>\n",
+       "      <td>2</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>81</td>\n",
+       "      <td>23.0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>3</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   postId  Score  userId  ViewCount  CommentCount\n",
+       "0       1     23     8.0     1278.0             1\n",
+       "1       2     22    24.0     8198.0             1\n",
+       "2       3     54    18.0     3613.0             4\n",
+       "3       4     13    23.0     5224.0             2\n",
+       "4       5     81    23.0        NaN             3"
+      ]
+     },
+     "execution_count": 12,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "posts=posts_raw[['postId', 'Score','userId','ViewCount','CommentCount']]\n",
+    "posts.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 7. Merge both dataframes, users and posts. \n",
+    "You will need to make a [merge](https://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.merge.html) of posts and users dataframes."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>userId</th>\n",
+       "      <th>Reputation</th>\n",
+       "      <th>Views</th>\n",
+       "      <th>UpVotes</th>\n",
+       "      <th>DownVotes</th>\n",
+       "      <th>postId</th>\n",
+       "      <th>Score</th>\n",
+       "      <th>ViewCount</th>\n",
+       "      <th>CommentCount</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>2175</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8576</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8578</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8981</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8982</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   userId  Reputation  Views  UpVotes  DownVotes  postId  Score  ViewCount  \\\n",
+       "0      -1           1      0     5007       1920    2175      0        NaN   \n",
+       "1      -1           1      0     5007       1920    8576      0        NaN   \n",
+       "2      -1           1      0     5007       1920    8578      0        NaN   \n",
+       "3      -1           1      0     5007       1920    8981      0        NaN   \n",
+       "4      -1           1      0     5007       1920    8982      0        NaN   \n",
+       "\n",
+       "   CommentCount  \n",
+       "0             0  \n",
+       "1             0  \n",
+       "2             0  \n",
+       "3             0  \n",
+       "4             0  "
+      ]
+     },
+     "execution_count": 20,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "users_posts = users.merge(posts, how='inner', on='userId')\n",
+    "users_posts.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 8. How many missing values do you have in your merged dataframe? On which columns?"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "ViewCount    23572\n",
+       "dtype: int64"
+      ]
+     },
+     "execution_count": 21,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "null_cols = users_posts.isnull().sum()\n",
+    "null_cols[null_cols>0]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 28,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>userId</th>\n",
+       "      <th>Reputation</th>\n",
+       "      <th>Views</th>\n",
+       "      <th>UpVotes</th>\n",
+       "      <th>DownVotes</th>\n",
+       "      <th>postId</th>\n",
+       "      <th>Score</th>\n",
+       "      <th>ViewCount</th>\n",
+       "      <th>CommentCount</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>2175</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8576</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8578</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8981</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8982</td>\n",
+       "      <td>0</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>...</th>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>212</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>3168</td>\n",
+       "      <td>5</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>3</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>213</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>3223</td>\n",
+       "      <td>4</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>1</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>214</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>3239</td>\n",
+       "      <td>15</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>5</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>215</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>3319</td>\n",
+       "      <td>3</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>1</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>216</th>\n",
+       "      <td>5</td>\n",
+       "      <td>6792</td>\n",
+       "      <td>1145</td>\n",
+       "      <td>662</td>\n",
+       "      <td>5</td>\n",
+       "      <td>3414</td>\n",
+       "      <td>6</td>\n",
+       "      <td>NaN</td>\n",
+       "      <td>4</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "<p>200 rows × 9 columns</p>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "     userId  Reputation  Views  UpVotes  DownVotes  postId  Score  ViewCount  \\\n",
+       "0        -1           1      0     5007       1920    2175      0        NaN   \n",
+       "1        -1           1      0     5007       1920    8576      0        NaN   \n",
+       "2        -1           1      0     5007       1920    8578      0        NaN   \n",
+       "3        -1           1      0     5007       1920    8981      0        NaN   \n",
+       "4        -1           1      0     5007       1920    8982      0        NaN   \n",
+       "..      ...         ...    ...      ...        ...     ...    ...        ...   \n",
+       "212       5        6792   1145      662          5    3168      5        NaN   \n",
+       "213       5        6792   1145      662          5    3223      4        NaN   \n",
+       "214       5        6792   1145      662          5    3239     15        NaN   \n",
+       "215       5        6792   1145      662          5    3319      3        NaN   \n",
+       "216       5        6792   1145      662          5    3414      6        NaN   \n",
+       "\n",
+       "     CommentCount  \n",
+       "0               0  \n",
+       "1               0  \n",
+       "2               0  \n",
+       "3               0  \n",
+       "4               0  \n",
+       "..            ...  \n",
+       "212             3  \n",
+       "213             1  \n",
+       "214             5  \n",
+       "215             1  \n",
+       "216             4  \n",
+       "\n",
+       "[200 rows x 9 columns]"
+      ]
+     },
+     "execution_count": 28,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "test_data = users_posts[users_posts['ViewCount'].isnull()==True]\n",
+    "test_data.head(200)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "11032    954\n",
+       "919      820\n",
+       "686      650\n",
+       "930      443\n",
+       "4505     383\n",
+       "        ... \n",
+       "7832       1\n",
+       "7829       1\n",
+       "7818       1\n",
+       "7792       1\n",
+       "55226      1\n",
+       "Name: userId, Length: 2618, dtype: int64"
+      ]
+     },
+     "execution_count": 27,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "test_data['userId'].value_counts()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 9. You will need to make something with missing values.  Will you clean or filling them? Explain. \n",
+    "**Remember** to check the results of your code before passing to the next step"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 30,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Considering only ViewCount is null and we do have around 2618 records with that value, we can fill the column with zero if it is null and it should be safe for statistical purposes\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Considering only ViewCount is null and we do have around 2618 records with that value, we can fill the column with zero if it is null and it should be safe for statistical purposes\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### 10. Adjust the data types in order to avoid future issues. Which ones should be changed? "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 31,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>userId</th>\n",
+       "      <th>Reputation</th>\n",
+       "      <th>Views</th>\n",
+       "      <th>UpVotes</th>\n",
+       "      <th>DownVotes</th>\n",
+       "      <th>postId</th>\n",
+       "      <th>Score</th>\n",
+       "      <th>ViewCount</th>\n",
+       "      <th>CommentCount</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>2175</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0.0</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8576</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0.0</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8578</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0.0</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8981</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0.0</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>-1</td>\n",
+       "      <td>1</td>\n",
+       "      <td>0</td>\n",
+       "      <td>5007</td>\n",
+       "      <td>1920</td>\n",
+       "      <td>8982</td>\n",
+       "      <td>0</td>\n",
+       "      <td>0.0</td>\n",
+       "      <td>0</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   userId  Reputation  Views  UpVotes  DownVotes  postId  Score  ViewCount  \\\n",
+       "0      -1           1      0     5007       1920    2175      0        0.0   \n",
+       "1      -1           1      0     5007       1920    8576      0        0.0   \n",
+       "2      -1           1      0     5007       1920    8578      0        0.0   \n",
+       "3      -1           1      0     5007       1920    8981      0        0.0   \n",
+       "4      -1           1      0     5007       1920    8982      0        0.0   \n",
+       "\n",
+       "   CommentCount  \n",
+       "0             0  \n",
+       "1             0  \n",
+       "2             0  \n",
+       "3             0  \n",
+       "4             0  "
+      ]
+     },
+     "execution_count": 31,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "users_posts['ViewCount'] = users_posts['ViewCount'].fillna(0)\n",
+    "users_posts.head()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "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": "3.10.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}