Tag Archives: trim

A sample dirty dataset for trying out Google Refine

I’ve created this spreadsheet of ‘dirty data‘ to demonstrate some typical problems that data cleaning tools and techniques can be used for:

  • Subheadings that are only used once (and you need them in each row where they apply)
  • Odd characters that stand for something else (e.g. a space or ampersand)
  • Different entries that mean the same thing, either because they are lacking pieces of information, or have been mistyped, or inconsistently formatted

It’s best used alongside this post introducing basic features of Google Refine. But you can also use it to explore more simple techniques in spreadsheets like Find and replace; the TRIM function (and alternative solutions); and the functions UPPER, LOWER, and PROPER (which convert text into all upper case, lower case, and titlecase respectively).

Thanks to Eva Constantaras for suggesting the idea.

UPDATE: Peter Verweij has put together an introduction to some other cleaning techniques here.

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Data journalism pt2: Interrogating data

This is a draft from a book chapter on data journalism (the first, on gathering data, is here). I’d really appreciate any additions or comments you can make – particularly around ways of spotting stories in data, and mistakes to avoid.

UPDATE: It has now been published in The Online Journalism Handbook.

“One of the most important (and least technical) skills in understanding data is asking good questions. An appropriate question shares an interest you have in the data, tries to convey it to others, and is curiosity-oriented rather than math-oriented. Visualizing data is just like any other type of communication: success is defined by your audience’s ability to pick up on, and be excited about, your insight.” (Fry, 2008, p4)

Once you have the data you need to see if there is a story buried within it. The great advantage of computer processing is that it makes it easier to sort, filter, compare and search information in different ways to get to the heart of what – if anything – it reveals. Continue reading