Checking the numbers
For networks who encourage the sort of censorship that would be shouted down if it happened to their broadcasts (how many minutes of coverage was available in comparison to competitors?).
For sites who use polls from the same company that owns their daily news page to support the pieces they publish (thanks for the belated acknowledgement of that connection).
For outlets that put out personal stories of people who reflect the outlet's opinion of those who pointed out their bias (my goodness, but that did hit a nerve, professor).
For moderators whose decisions on content (and rather telling exceptions - nice video) aim to twist perception and hit people on two sides of a political divide.
For the talking heads connected to any and all of the above.
(Also, from virginity to pregnancy tests and maternity clothes? Make up your hive mind, Recommendations. Weirdos.)