Sandro Saitta, Data Mining Research Blog

Cross Validated is a free, community-driven question and answer site for statisticians, data analysts, data miners, and data visualization experts. It is part of the Stack Exchange network of Q&A websites, and it was created through the open democratic process defined at Stack Exchange Area 51. What’s so special about this? Well, nothing, really. But we synthesize aspects of wikis, blogs, forums, and Digg/Reddit in a way we think allows for the best quality answers and interface for exchanging knowledge.

We interviewed Rob Hyndman about his experiences with the website as a statistics resource for professionals and students.

Could you introduce yourself and explain your relationship to statistics?

I am professor of statistics at Monash University, Australia, and editor-in-chief of the International Journal of Forecasting. I’m probably best known for my work in statistical forecasting; I am author of the forecast package for R and I’ve written a couple of books on forecasting. I joined the ASA after I finished my first degree and have remained a member ever since.

What is Cross Validated, and how does it help in your work?

Cross Validated is a website where people can ask and answer questions about statistical topics. The site is part of the Stack Exchange network of sites, all of which are free, community-driven expert Q&A sites around particular topics. We [online community members] interpret statistics quite broadly—the site is intended for statisticians, data miners, and anyone else doing data analysis.

When I proposed the site in April 2010 [in Stack Exchange’s new site hatchery called Area 51], I had in mind it being useful for the thousands of researchers using statistical methods, but who may not have enough statistical training to be confident they are using the best methods and implementing them appropriately. Having spent a couple of decades as a statistical consultant, I thought it would be nice to have a good site I could recommend to people, rather than trying to answer every question myself. It’s turned into something much bigger than that and is now a wonderful resource for everyone doing statistics, even those who have years of experience.

Having proposed the site, I was one of the first [community] moderators when it launched in July 2010. After about six months, I decided to take a back seat and some of the most reputable users formed a new moderation panel. They are doing a great job and I’m delighted to see the site being so active and obviously meeting the needs of so many people.

One of the nice things about Cross Validated and other Stack Exchange sites is that the good answers get voted up and it is easy to see what the community regards as the best answer. You also can see which of the people answering has established a reputation for providing helpful advice based on their reputation scores. It is also extremely easy to find answers to past questions. This sets it apart from email lists and forums, where you have to search through badly formatted archives. Everything is tagged and searchable, and (as of October 5) there are more than 5,300 questions and more than 10,000 answers that provide a repository of useful knowledge that is freely available.

Do you recommend Cross Validated to your students and colleagues?

I recommend Cross Validated all the time. I’ve promoted it on my blog and I often refer people to Cross Validated when they send me questions by email. So it has helped in filtering out some of the questions that otherwise would land on my desk. I will now usually suggest that if someone has a specific question, they ask on Cross Validated first. Very often, the answers are faster and better than what I would have provided. There is a wonderful community of people on Cross Validated (more than 5,000 of them) who are very helpful and willing to share their expertise.