Audris Mockus (Avaya Labs), Roy Fielding (eBuilt), 和James Herbsleb (Bell Laboratories)写了一篇关于开源项目是怎样运作的论文，很有内涵。论文的名字叫做"Two Case Studies of Open Source Software Development: Apache and Mozilla"。文章以Apache和Mozilla为研究对象，得出了几个有意思的结论：

Hypothesis 1a: Open source developments will have a core of developers who control the code base, and will create approximately 80% or more of the new functionality. If this core group uses only informal, ad hoc means of coordinating their work, it will be no larger than 10-15 people.

Hypothesis 2a: If a project is so large that more than 10-15 people are required to complete 80% of the code in the desired time frame, then other mechanisms, rather than just informal, ad hoc arrangements, will be required in order to coordinate the work. These mechanisms may include one or more of the following: explicit development processes, individual or group code ownership, and required inspections.

Hypothesis 3: In successful open source developments, a group larger by an order of magnitude than the core will repair defects, and a yet larger group (by another order of magnitude) will report problems. (一个好的开源项目一定要有一个庞大的社区来反馈问题，判断一个Linux发行版好不好，看看它的用户社区和技术支持，为什么我喜欢Gentoo, 这是原因之一)

Hypothesis 4: Open source developments that have a strong core of developers but never achieve large numbers of contributors beyond that core will be able to create new functionality but will fail because of a lack of resources devoted to finding and repairing defects.

Hypothesis 6: In successful open source developments, the developers will also be users of the software. (很奇怪的一条结论 - 有开发者不用自己的作品的吗?)

Apache是一个很伟大的项目。在我看来，比Linux Kernel还要伟大。