Aspect | Data Wrangling (Data Preprocessing) | Exploratory Data Analysis (EDA) |
Objective | Prepare raw data for modeling by cleaning, transforming, and formatting it appropriately. | Explore and understand the data to gain insights, identify patterns, and make decisions on data handling and modeling. |
Order | Typically performed as a preliminary step before EDA. | Usually conducted after data wrangling to further investigate data characteristics. |
Data Handling | Focuses on data cleaning, filling missing values, encoding categorical variables, and scaling features. | Involves data visualization, statistical analysis, and summary statistics to uncover patterns, relationships, and anomalies. |
Techniques | Techniques include imputation, outlier detection, feature scaling, and one-hot encoding. | Techniques include histograms, scatter plots, box plots, correlation matrices, and descriptive statistics. |
Data Transformation | Involves structural changes to the dataset, such as feature engineering, data normalization, and dimensionality reduction. | Primarily explores existing data structures and relationships without altering the data's fundamental structure. |
Tools | Common tools include libraries like pandas and scikit-learn in Python. | Utilizes tools like matplotlib, seaborn, and statistical analysis packages (e.g., R) for visualization and analysis. |
Outputs | The output is a clean, preprocessed dataset ready for model training. | The output includes visualizations, summary statistics, and insights used for feature selection, model choice, and problem understanding. |
Purpose | Aims to prepare data in a format suitable for machine learning algorithms, ensuring they can effectively learn from the data. | Aims to uncover data characteristics, relationships, and potential challenges to inform modeling decisions. |
Iteration | Often an iterative process, as issues discovered during EDA may require revisiting data wrangling steps. | Typically a one-time or limited iteration process to understand the data before modeling. |
Examples | Removing duplicate records, filling missing values, scaling features, encoding categorical variables. | Creating histograms to visualize data distributions, generating scatter plots to examine relationships between variables, calculating summary statistics. |
Comments