crossvalidated

Cross Validated is a question-and-answer site on the Stack Exchange network that focuses on statistics, data analysis, and related topics. It provides a forum for researchers, practitioners, and students to ask questions, share methods, and obtain expert explanations. The site covers a broad range of statistical topics and aims to facilitate precise understanding and practical guidance.

On-topic areas include probability theory, statistical modeling, experimental design, sampling methods, hypothesis testing, Bayesian inference, regression and multivariate analysis, time series, and machine learning as it relates to statistics. Questions about data interpretation, study design, and model validation are common. Answers are expected to be well-reasoned, supported by references or worked examples, and often include code snippets to illustrate methods or reproduce results.

The site operates under the Stack Exchange model, featuring a voting system, acceptance of answers, and reputation-based privileges. Questions are tagged to indicate subtopics, aiding navigation and expert attention. The community emphasizes clear problem statements, reproducible examples, and respectful discourse, with a Help Center outlining guidelines for asking well-posed questions and providing constructive answers. Reproducibility and careful mathematical notation are encouraged.

History and impact: Cross Validated began as part of the Stack Exchange network in the early 2010s and has since grown into a central resource for statistics professionals, students, and researchers. It serves as a practical reference for statistical methods, data analysis dilemmas, and software implementation across tools such as R and Python, as well as other statistical software.