Question

You use pandora (an automated internet radio service) to build a collection of songs you like. when you select certain songs or artists, pandora will play selections that are musically similar and you can approve or disapprove of the selections. the selections are determined by other pandora users who have selected the same or similar songs/artists and categorized them together based on their own approval/disapproval decisions. this scenario is an example of:

Answer 1

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