Sometimes data is messy and needs cleaning before you can analyze and visualize the data. For example, to merge different spellings (e.g. ‘Denmark’ and ‘DK’) or to delete blanks before a number. OpenRefine is an open source and free tool, which can help you clean messy data.
On the course you will have the opportunity to:

• Discuss the differences between the datatypes: string (text), number, date, boolean (binary, e.g. TRUE or FALSE) and arrays (lists).
• Import an excel-file to OpenRefine.
• Work with several data cleaning options in OpenRefine.
• Edit the data via OpenRefine’s graphical user interface as well as via simple coding.
• Export the file to excel after the cleaning.

You can work with your own data (excel-file), or you can use the excel-file provided by the instructor. If you bring your own file, you will have the opportunity to test whether OpenRefine is the right tool for your data.

This is a basic introduction, so you are not expected to have worked with OpenRefine before the course.

Preparation:

• Install OpenRefine on your computer: https://openrefine.org/download.html
• If possible, bring your own excel-file with messy data. If you have specific questions about how to clean you data, please send the question and excel-file to kubdatalab@kb.dk at least two days before the course. 

After the course you should have:

• A basic understanding of OpenRefine – for which data types and tasks you can use the tool.
• Imported/exported an excel file to/from OpenRefine.
• Worked with simple data cleaning operations via OpenRefine’s graphical user interface and via OpenRefine’s coding options (GREL and Regular Expressions).

Materials

• Instructor’s presentation (to be uploadet)
• Exercises that we will use at the course (to be uploadet)
• Excel file that you can use if you do not have your own data with you for the course (to be uploaded)
• Introduction to OpenRefine (textbook) https://ruben.verborgh.org/publications/verborgh_packt_2013/ - Copenhagen University Library has an electronic copy

Practical information

Please note: If there are non-Danish speakers, this course will take place in English. (If all attendees are Danish speakers, it will take place in Danish.)