Brooke shared a great link this week about how brands have, and continue to, struggle with tying their social media efforts and spending to return on investment. It’s a great post, and you should check it out, but it’s also a really frustrating one.

It’s frustrating because there seems to be a double standard when it comes to paid and earned media. Most mid- to large-sized brands have, at some point, purchased a billboard or radio ad, and felt good about it because it delivered them X amount of impressions. How do we get those impressions? Who knows. It’s an assumed based on, X amount of people drive by there every day, and that data comes from some traffic study done some number of years ago.

With earned social media, we know exactly how many people have seen an ad—that’s what branded social media posts are—how many of them chose to interact with it, and we can even take steps to roughly, but still pretty accurately, quantify how much actual revenue the ad generated.

Why, then, is earned media held to such a stricter proof of ROI than traditional paid media?

I’m not saying that social media shouldn’t be held to a strict proof of ROI. But I am asking why it seems so inherently easy to consider an ad buy of X impressions a success, while a social campaign with the same number of impressions would just as easily be looked upon with suspicion because it couldn’t prove a direct tie to business results.

I’m also not simply saying this isn’t fair—my point is that if you’re struggling to understand what social media can contribute to your business, you should ask yourself if you can draw an A-to-B line from your paid media efforts to your business’ bottom line as well. Because an Instagram post costs a hell of a lot less than space on a billboard, and in a lot of cases, it’s driving the same return: eyeballs.

Realistically, until we come to a Minority Report-style world where consumers’ every movements are tracked, there’s always going to be some level of educated guesswork with ROI. But it makes the most business sense to measure the effectiveness of all media efforts—paid, earned, traditional, non-traditional—against the question, “What does this do for the business?” and treat all answers equally.