In fact, I'll go farther and say I think so much focus on statistics can hurt a writer's income, because we then learn that mysterious, meaningless stats are the key to earning, and our intuition is worthless. And that's not true.
You can't ignore stats, but the key is to think in terms of marketing. When you understand that writers who are earning by revenue sharing are not just writers, but marketers, as well, you have made an important step toward earning online by writing articles for revenue share.
Why is a marketing mindset important? Well, the Internet started as an academic thing, but around 1996-ish, the web changed. It became commercial. The growing need for paid content on the Internet is at the moment directly related to the need to provide content for advertisers.
There are other ways to earn money online writing - for instance, by selling your content on commission through Constant-Content. But to earn money with revenue sharing articles at HubPages, Suite101, InfoBarrel, or other sites, a writer writes an article that is, at his or her conscious or unconscious instigation, whether directly or indirectly, advertising copy.
I belabor that point because I've learned it's not necessarily the mindset of beginning revenue share writers, especially those previously published in print.
Knowing you're a marketer, not just a writer, doesn't mean you have to sell your soul to the devil and write about products you don't approve of or lie about them. It just means you need a marketing related mindset when you write about things. This doesn't mean being a salesman. A marketing mindset is simply one that involves persuasion. Some writers do this instinctively just by offering their opinions; other writers craft their words consciously.
Writers tend to be really good at marketing, because it's what we do anyway when we write fiction or present an argument - we persuade people something is true. When you write revenue sharing articles, that's what you also do - persuade them something is true. And the dandy thing is, because you work for yourself, you can make sure you only write what you think is the truth and promote products you do like. No great moral stress here.
The thing about a marketing mindset is that it gets you thinking about what advertisers are thinking about - specifically, products. In each article, there's a product - either implied or directly mentioned.
If you don't have experience or training in marketing, to figure out articles that are potential earners in the real world, without using the CPC metric, but rather by flexing your marketing muscle, try this:
Look at yourself, your parents, your relatives, your coworkers, your teachers, and your friends. Ask yourself - what would they buy on the Internet to solve a pressing problem? What have they bought in the past?
With a global online community, each person you know, no matter how unusual or quirky, represents a microcosm of a much larger group of people spread out all over the world.
It could be anything from a girdle to an accessory for a musical instrument, from software to a vitamin supplement to a DVD they've been wanting but that isn't locally available.
Then ask yourself what sort of article would they be reading when they're in the frame of mind to buy that product. Then check to see if there are already articles out there that are like that, that are already accessible by a wide variety of keywords. If so, writing the article will probably only get you short term earnings, if at all. Don't bother, I'd say.
But if not...write the article. Do pay attention to keywords and competition, but don't pay too much attention to CPC. If you don't believe me, try it the other way first. Then report back here whether you think knowing the CPC really made a difference to your success.