How loud is a Buzzing Community of Practice?

---

I posted last week on large communities of practice, and referenced the community of School Leaders in the UK, as described in the excellent publication from the National College for School Leadership "100,000 heads are better than one (lessons from the worlds largest online learning community)".

Within this document, they talk about activity levels, and the level of community "Buzz". They answer the question "How loud should the buzz be?" as follows

As a rule of thumb, a good level of buzz is generated if, in one month,
for a large community of practice (more than 50,000 members): 

• 10 per cent of members visit 

• 15 per cent of visitors contribute 

• each contributor leaves between two and three contributions 

 for a smaller community set up to meet a need or complete a project: 

• 75 per cent of members visit 

• 50 per cent of visitors contribute 

• each contributor leaves between four and five contributions 

For a learning group set up around a ftf event, where all participants are expected to visit as part of the event:

• 100 per cent of members visit 

• 100 per cent of visitors contribute 

• each contributor leaves more than five contributions