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← Types of Data Quiz 1 - Intro to Machine Learning

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Showing Revision 3 created 05/25/2016 by Udacity Robot.

  1. Let's say a few words about types of data.
  2. It's something that's come up in this class already, but let's make it
  3. a little bit more explicit so that you know that it's something to look out for.
  4. Here are a few important types of data that you should be aware of.
  5. One is numerical.
  6. So something like salary information would be an example of
  7. a numerical variable, where basically the feature is a number.
  8. Another thing that we've talked a lot about in the context of
  9. supervised classification is categorical features.
  10. These can take on a limited number of discrete values.
  11. So, a cat, an example of a categorical feature would be the class label.
  12. This would also be something like if a person is a man or
  13. a woman, or maybe how many stars you give when you're rating a movie.
  14. Although stars, you might argue, could also be called a numerical value.
  15. Another one that's very important, especially in particular fields like finance,
  16. is time series data.
  17. This is data that has a temporal value attached to it, so this would be
  18. something like a date or a time stamp that you can look for trends in time.
  19. One that we're already very familiar with, text data,
  20. which is basically just words.
  21. A lot of the time the first thing that you do with text is you turn it
  22. into numbers using some interesting functions that we'll,
  23. that we'll learn about, things like the bag of words formulation.
  24. So these are all types of data that you might encounter, and depending on
  25. exactly the type of data, this might have some repercussions for the type of
  26. algorithm that you can use or the type of questions that you can ask of it.
  27. So let me get you a quiz just to practice this.
  28. I'm going to give you a bunch of types of features you might see and
  29. ask you what type of data that feature is.
  30. First example is salary information.
  31. Would you call this numerical, categorical, time series, text, or
  32. let's put other on the list as well because this isn't a complete list.