Skills are parsed through Daxtra and added to Mercury automatically. These are scored, depending on how they appear in the CV.
The skills Proficiency Level is based on an algorithm built by DaXtra out of a score of 1 to 100. The algorithm is based on number of key words but also more intelligent data, such as how recently does it appear in the CV.
Along with the skill level, it assigns a Proficiency. This can then be used when searching for people on the internal candidate search.
Searching
Open Refinements and select to only see candidates with a certain Skill level.
Parsed skills can then be used in Mercury Legacy Search. You can search for Candidates with specific skills and by how the skills were scored. The icon for skills is a yellow star.
As you can see above, not only can you search for candidates with that particular skill, but you can specific the level of proficiency that candidate has. This is great for drilling down into numbers.