This question illustrates the difficulty of a person mastering statistics and probability on their own, in the face of weakly developed resources like Wikipedia.
It occurred to me that consulting statisticians, and there are a few here, may routinely face the challenge of explaining certain concepts and methods to a client. This is the flip side of the pedagogical coin. When one has mastered the concept, it may make sense to conduct a particular avenue of analyses, but one's references may either be inappropriate or difficult to share with a client. So, are there common resources that consulting statisticians like to suggest to their clients? (See update #1 regarding more advanced or specialized topics.)
I can think of a few books that may be useful, but I suspect that a lot of clients will go about searching the web, as Developer did, and will come across rather inane material on Wikipedia. In my answer to Developer, I suggested the NIST Handbook as one such reference that could be used. What else?
Update 1: As Peter Flom has pointed out, for more advanced material or narrower pursuits, it may not be easy to offer a single point of reference. This is correct and I should have worded the question differently for those cases. In such cases, how do consultants find and share accessible references? I believe that many consultants will take the time to write something new in order to explain things to their client, but those aren't references that are found and shared.
- Tutorials written by the consultant or others
- Case studies or analyses from projects that demonstrate the same concepts
- Excerpts of books (as I'd suggested in my answer to Developer), which describe the concept
What else might be a source or how else do you actually go about finding such references? I realize this is an open ended question, but my answer to Developer shows some of the ways I'd approach this problem. I don't mean to ask of all the ways that one could address this, but in one's own experience, how have you typically provided such explanatory resources?