I liked this post so much that I came back to it after upvoting and may now have to resteem it. I've been asking questions about PKIs for a while now (well, ever since I joined Steemit). This article actually makes an effort to define them. Kudos, Matt.

That said, I view Projected Weekly SP Growth as equivalent to the accounts receivable balance for a business. The business has down the work for a number of clients, and now it's just waiting for the cash to flow in on existing contracts. But there are so many other indicators that are more solid PKIs, and they depend on the industry. For oil and gas, it's the number of producing wells that are online. For defense contractors, it's the monetary amount of newly signed contracts with the government. For retail, it's the monthly growth of same-store sales. And of course, there is the beta market factor in CAPM to consider. That is, what the overall market does as a whole (due to the overall economy) can have more impact to stock price than the underlying fundamentals of the business firm.

I think we need to do some more digging here to find the PKIs for Steem. I think one way to figure this out would be a thought experiment asking what it would take to maximize revenue on Steemit. To do that, you would want to have a lot of followers with high rep who are also loyal to you (they upvote everything that you post). Also, you would want to maximize the number of articles you post (recognizing that there are diminishing returns to this, as followers start to think of high frequency posting as spam).

If you accept that, then a Steem PKI would be an equation of these variables:

• FL = loyalty factor of your followers
• FR = the total reputation of followers who are loyal to you
• PA = post activity (number of articles you post per week/month)

Well, those are the relevant variables for posting revenue. Commenting revenue is another good source, so we need to include:

• CR = reputation of the people whose articles you comment on
• CL = loyalty of the people whose articles you comment on (e.g., how often they upvote your comments)
• CA = comment activity (number of comments you write per week/month)

I'll skip the curation calculation because I don't have experience with that. I suspect it would depend on bots targeting specific high-rep individuals who generate a lot of revenue from their posts.