conclusions_query.ipynb

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 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Drawing Conclusions Using Query"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "import pandas as pd"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "# Load `winequality_edited.csv`\n",
    "\n",
    "df = pd.read_csv('winequality_edited.csv')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "<class 'pandas.core.frame.DataFrame'>\n",
      "RangeIndex: 6497 entries, 0 to 6496\n",
      "Data columns (total 14 columns):\n",
      "fixed_acidity           6497 non-null float64\n",
      "volatile_acidity        6497 non-null float64\n",
      "citric_acid             6497 non-null float64\n",
      "residual_sugar          6497 non-null float64\n",
      "chlorides               6497 non-null float64\n",
      "free_sulfur_dioxide     6497 non-null float64\n",
      "total_sulfur_dioxide    6497 non-null float64\n",
      "density                 6497 non-null float64\n",
      "pH                      6497 non-null float64\n",
      "sulphates               6497 non-null float64\n",
      "alcohol                 6497 non-null float64\n",
      "quality                 6497 non-null int64\n",
      "color                   6497 non-null object\n",
      "acidity_levels          6496 non-null object\n",
      "dtypes: float64(11), int64(1), object(2)\n",
      "memory usage: 710.7+ KB\n"
     ]
    }
   ],
   "source": [
    "df.info()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "collapsed": true
   },
   "source": [
    "### Do wines with higher alcoholic content receive better ratings?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "10.3"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# get the median amount of alcohol content\n",
    "df['alcohol'].median()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# select samples with alcohol content less than the median\n",
    "low_alcohol = df.query('alcohol < 10.3')\n",
    "\n",
    "# select samples with alcohol content greater than or equal to the median\n",
    "high_alcohol = df.query('alcohol >= 10.3')\n",
    "\n",
    "# ensure these queries included each sample exactly once\n",
    "num_samples = df.shape[0]\n",
    "num_samples == low_alcohol['quality'].count() + high_alcohol['quality'].count() # should be True"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "5.475920679886686"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# get mean quality rating for the low alcohol and high alcohol groups\n",
    "low_alcohol['quality'].mean()\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6.1460843373493974"
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "high_alcohol['quality'].mean()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### QUESTION 1 OF 2\n",
    "\n",
    "*Do wines with higher alcoholic content generally receive better ratings?*\n",
    "Yes"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Do sweeter wines receive better ratings?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "3.0"
      ]
     },
     "execution_count": 13,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# get the median amount of residual sugar\n",
    "df['residual_sugar'].median()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# select samples with residual sugar less than the median\n",
    "low_sugar = df.query('residual_sugar < 3.0')\n",
    "\n",
    "# select samples with residual sugar greater than or equal to the median\n",
    "high_sugar = df.query('residual_sugar >= 3.0')\n",
    "\n",
    "# ensure these queries included each sample exactly once\n",
    "num_samples == low_sugar['quality'].count() + high_sugar['quality'].count() # should be True"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "5.8088007437248219"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# get mean quality rating for the low sugar groups\n",
    "low_sugar['quality'].mean()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "5.8278287461773699"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# get mean quality rating for the high sugar groups\n",
    "high_sugar['quality'].mean()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### QUESTION 2 OF 2\n",
    "\n",
    "*Do sweeter wines generally receive higher ratings?*\n",
    "Yes"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
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