How Can You Measure if Ads Work?

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Today I planned to write an article for my Monday blog about the benefits of writing content and giving readers samples of your work – rather than posting ads for their books. I was already sitting in front of my laptop, clicking through my Google+ timeline, when I stumbled over a post that made me stop in the tracks:

For the second time this week, I heardfrom authors that their ads at book promo sites don’t work (anymore). The first article just made me feel like: He didn’t plan his market...