Atelier de Visualisation des Données avec OpenRefine

📚 Mastère de Recherche en Sciences des Données (2019-2020) at ISIMS, led by Anis Jedidi, covered data cleaning using Open Refine in the Data Visualization workshop.

🔑 Key points:

• Open Refine: http://openrefine.org/
• Data exploration: understanding the number of columns and rows, examining column headers and their values, discovering data types, and checking for errors.
• Common data issues: spelling errors, white spaces, various date formats, number formatting, and missing values.

🤝 What is Open Refine: Open Refine is a powerful tool for data cleaning, transformation, and extension. It's particularly helpful when dealing with messy data, as it offers features that make it easier to manipulate and prepare data for analysis.

🛠️ Installation and Execution:

1. Download OpenRefine: https://openrefine.org/download.html
2. Extract the downloaded folder and launch the application by running the "refine-server" file.
3. Explore your data and understand its structure.

🔎 Data Exploration:

• Identify the number of columns and rows.
• Inspect column headers and their values.
• Determine data types (numbers, text, dates, etc.).
• Find maximum and minimum values using sorting.

💔 Common Data Mess:

• Spelling errors: 'NY' vs 'N.Y.' and 'N.Y.'
• White spaces: leading and trailing spaces
• Differently-formatted dates: '01/10/2013', '10.2013', 'October 2013', '01.10.2013 12:00:34'
• Number formatting: '£100' as a number or text
• Missing values: incomplete columns with missing data

💡 Additional Context:

• The text also mentions an Excel course by Anis Jedidi, covering formulas and functions, lists and tables, filtering and searching, dynamic table crossings, external data, and more.
• A table is provided to help create an Excel table with given data.

Découvrez l'atelier de visualisation des données avec OpenRefine. Apprenez à télécharger, installer et exécuter l'application OpenRefine pour explorer vos données et vous initier au nettoyage des données.