The more a user shared links to the site, the more likely they were to win.

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There was a time when we all shared links to the latest pronouncements from Ivy League econ departments.

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Your actively shared links, photos, and status updates probably reach much higher than 16 percent of your friends, while more inane auto-generated posts about new friendships, wall posts, and articles you read may only be seen by your closest buddies.

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