Everyone uses rating scales, with our first introduction in elementary school. Most schools use 0 - 100 or A - F, then in college it becomes GPA of 0.0 (Mr. Blutarsky!!) to 4.0. In many areas of business, a different scale is often used: 1 - 5. The scale was invented by Rensis Likert for his PhD thesis. The first popular instance I can trace is Phil Crosby's Quality Management Maturity Grid. Lots of customer satisfaction models use a 1 - 5 score, as does the Capability Maturity Model for software engineering. A rating of 1 is out of kindness and may mask the reality that you're nowhere. I prefer to call a 0 a zero and acknowledge people and organizations by giving a 1 to those that have at least made a start of it. I use a similar scale when calibrating the level of expertise a person has in any field. It helps to making sure you have the right person for the job.
Level / Descriptor / Characteristics
0 Ignorant: Never heard of it
1 Aware: Minimal awareness (heard of it), but little understanding
2 Novice: Beginner's understanding, can listen to a conversation and understand some concepts, with very limited contribution
3 Literate: Understand most everything that is said, can contribute to the conversation in ways valued by the group
4 Fluent: Know the domain in-depth, an important contributor in sorting out issues
5 Expert: Practitioner with authoritative experience and contributor to body of knowledge whom people seek out on key issues
The word Literate is in bold because I believe that every participant should be a 3 or better, with some 2s in the mix so they can deepen their expertise with the support of those ahead of them. So much of what we do at work uses acquired knowledge, not innate. A friend cautioned a young colleague with a stereotypical youthful hubris to study for a licensing exam because 'nobody is born with this knowledge'. [NB: colleague ignored this advice and flunked on the first go through before he got religion and studied, and passed… imagine that.] Every Expert at Level 5 started out at 0. It's OK to be below 3; it's not OK to stay there. The scale is not linear; it may not be precise, but it's probably more of a log scale. Going from 0 to 1 is so easy -- just use Wikipedia. Some professors reject citations from Wikipedia as not being from a scholarly work, but it can start an inquiry and lead you to deeper understanding. Knowing something about a subject enables you to know more.
Knowledge has become a commodity... applying it is the value-added. But you can't apply it if you don't have it. So... getting from 0 to 1 is easy. How do you climb? More to follow.