Physical Environment

Another finding from DeMarco and Lister's war games was that the developers whose productivity was in the top 25 percent had bigger, quieter, more private offices and fewer interruptions from people and phone calls than the other 75 percent. The differences in physical space weren't all that dramatic. The top 25 percent performers had an average of 78 square feet of dedicated floor space; the bottom 25 percent had 46 square feet.

The differences in productivity were more dramatic. Developers in the top quartile had productivity 2.6 times better than developers in the bottom 25 percent. In Cocomo II terms, the influence of office environment between the top tier (top quartile) and bottom tier (bottom quartile) is 2.6.