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Data Analysis Workflow

This guide walks you through the exploratory data analysis workflow using analyze.ipynb. You’ll learn how to uncover insights, identify feature correlations, and understand the dataset characteristics.

Prerequisites

Before starting, ensure you have:
  • Jupyter Notebook or JupyterLab installed
  • Required Python packages (pandas, numpy, kagglehub)
  • Internet connection to download the dataset

Launching the Analysis Notebook

1

Navigate to the notebooks directory

cd notebooks
2

Launch Jupyter Notebook

jupyter notebook analyze.ipynb
Or if using JupyterLab:
jupyter lab analyze.ipynb
3

Run all cells sequentially

Click Cell > Run All or execute each cell individually with Shift + Enter

What You’ll Discover

1. Dataset Overview

The notebook first downloads and loads the Boston Housing dataset:
import kagglehub
import pandas as pd
import numpy as np

# Download latest version
path = kagglehub.dataset_download("arunjangir245/boston-housing-dataset")
df = pd.read_csv(path + '/BostonHousing.csv')
Expected Output:
  • Dataset shape: 506 rows × 14 columns
  • Features include: crim, zn, indus, chas, nox, rm, age, dis, rad, tax, ptratio, b, lstat
  • Target variable: medv (median home value)

2. Data Quality Assessment

The notebook identifies missing data:
Missing Values:
    Missing Count  Missing %
rm              5   0.988142

Total missing values: 5
Only the rm (average number of rooms) feature has 5 missing values (0.99%) - a minimal amount that can be easily handled during preprocessing.

3. Feature Correlation Analysis

The most critical insight comes from correlation analysis with the target variable (medv):
# Top features positively correlated with house prices
rm         0.6962  # Average number of rooms
zn         0.3604  # Proportion of large residential lots  
b          0.3335  # Demographic factor
dis        0.2499  # Distance to employment centers
Key Finding: The strongest predictor is lstat (correlation: -0.74), indicating that neighborhoods with higher percentages of lower-status population have significantly lower home values. The second strongest is rm (correlation: 0.70), showing that larger homes command higher prices.

4. Statistical Summary

The notebook provides comprehensive statistics for each feature:
# Example for target variable (medv)
count    506.000000
mean      22.532806   # Average home value: $22.5k
std        9.197104
min        5.000000
max       50.000000

5. Feature Interpretation Guide

The notebook includes a detailed markdown section explaining what drives housing prices:
Housing values in this dataset reflect five macro factors:
  1. Size & Spacerm (rooms), zn (zoning for large lots)
  2. Socioeconomic Statuslstat (lower status %), b (demographics)
  3. Education Qualityptratio (student-teacher ratio)
  4. Environmental Qualitynox (pollution), indus (industrial %)
  5. Safety & Costscrim (crime rate), tax (property tax)
Core Insight:
Housing Price ≈ Space + Income Level + School Quality + 
                Environmental Quality + Safety − Cost Burden

6. Outlier Detection

The IQR (Interquartile Range) method identifies outliers:
Columns with outliers:
  crim: 66 outliers (13.04%)
  zn: 68 outliers (13.44%)
  rm: 30 outliers (5.93%)
  b: 77 outliers (15.22%)
  medv: 40 outliers (7.91%)

How to Identify Important Features

After running the analysis, use these correlation insights to:
  1. Select features for modeling - Focus on features with |correlation| > 0.5:
    • lstat, rm, ptratio, indus, tax, nox
  2. Understand feature relationships - Note that some features are highly correlated with each other:
    • rad and tax have correlation of 0.91 (multicollinearity alert!)
    • nox and dis have correlation of -0.77
  3. Prioritize feature engineering - Consider:
    • Polynomial features for rm (strong linear relationship)
    • Interaction terms between lstat and rm
    • Log transformations for skewed features like crim

Next Steps

After completing the data analysis:

Train Models

Use the insights to build predictive models

Compare Results

Evaluate which model performs best

Troubleshooting

If you encounter authentication errors:
  1. Create a Kaggle account at kaggle.com
  2. Go to Account Settings > API > Create New Token
  3. Place the downloaded kaggle.json in ~/.kaggle/
  4. Run: chmod 600 ~/.kaggle/kaggle.json
The first time you run the notebook, it downloads the dataset from Kaggle. This requires:
  • Active internet connection
  • Valid Kaggle API credentials
The dataset is cached locally for future runs.

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