Tidy Data Is Normalized Data

I emphasize the link between a tidy dataframe and a normalized data structure:

The kicker, as Wickham describes on pages 4-5, is that normalization is a critical part of tidying data.  Specifically, Wickham argues that tidy data should achieve third normal form.

Now, in practice, Wickham argues, we tend to need to denormalize data because analytics tools prefer having everything connected together, but the way we denormalize still retains a fairly normal structure:  we still treat observations and variables like we would in a normalized data structure, so we don’t try to pack multiple observations in the same row or multiple variables in the same column, reuse a column for multiple purposes, etc.

I had an inkling of this early on and figured I was onto something clever until I picked up Wickham’s vignette and read that yeah, that’s exactly the intent.

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