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What topics can I ask about here?
CrossValidated is for statisticians, data miners, and anyone else doing data analysis or interested in it as a discipline. If you have a question about
- statistical analysis - applied or theoretical
- designing experiments
- collecting data
- data mining
- machine learning
- visualizing data
- probability theory
- mathematical statistics
- statistical and data-driven computing
then you're in the right place. Anybody can ask a question, regardless of skills and experience, but some questions are still better than others. If you came here with a question to ask and are new to the site, please consult our thread on how to ask a good question.
Our community aims to create a lasting record of great solutions to questions. For more about this and guidance about how to provide your own great answers, please read How should questions be answered on Cross Validated? Providing references to peer-reviewed literature or links to on-line resources is warmly welcomed. You can also incorporate the work of others under fair use doctrine, which particularly means that you must attribute any text, images, or other material that is not originally yours.
[Edit: Converted the Homework link to SE markup for the Homework tag]
Homework questions are welcome. Please mark them with the homework tag. They get somewhat special treatment, because ultimately you benefit most by finding the solution yourself. The community will try to provide guidance, hints, and useful links.
For more help, see What types of questions should I avoid asking?
- Reordered bullets, collected all software-related entries into a single section
- Added a line to the Bugs bullet about appropriate reporting
- Under the programming sub-bullet I added a Note to clarify what we mean by programming. The other text in this bullet is a verbatim copy from the original
- Added several bullets under the general topic (which is also new) of Software-related Questions.
There are certain subjects that will probably get better responses on our sister sites. If your question is about
- Mathematics ask on math.stackexchange.com.
Bugs in software, ask the people who produced the software.
Added: For add-on packages for languages such as R, written by third parties, identify the author or package maintainer so as to make your bug report in the appropriate place.
Software-related questions Computers and statistical software are integral to the modern practice of statistics or data analysis. As such, questions with a significant software aspect are in general welcome on CV. However, the CV community has no desire to replace documentation or existing help email lists or discussion fora for statistical software. Consider whether a software-related question is suitable for CV via the following criteria:
that are potentially related to the practice of statistics or data analysis, however well-disguised as a coding or software issue they may be. Such questions should be assumed on topic for CV unless another criterion would render them off topic. Such questions may need improvement to meet other quality criteria; assist the original poster to improve the question to draw out the statistical or data analytical issues by leaving comments.
General questions about using
statistical functions, software or add-on packages for languages such as R, especially those concerning basic usage, are off topic on CV and SO, particularly so when they concern topics covered in the introductory manuals, or function or package documentation. As such, these questions should not in general be migrated or flagged for migration to SO.
Programming If the language is statistically oriented (such as R, SAS, Stata, SPSS, etc.), then decide based on the nature of your question: if it needs statistical expertise to understand or answer, ask it here; if it's about an algorithm, routine data processing, or details of the language, ask on Stack Overflow or refer to the collection of links to resources we maintain.
Note: With languages such as R or Python it can be difficult to distinguish between programming and simply using the software's functionality for data analysis. Questions about using higher-level statistical functions or add-on packages in such languages are not considered programming. Do not flag such questions for migration to SO.
If statistical reasoning is required to answer the question, the question is on topic. This criterion has broad applicability, for example a question requiring help with debugging code producing patently incorrect results is considered on topic if statistical reasoning is needed to correct the code.
additional criteria here
Questions about obtaining particular datasets are off-topic (they are too specialized). The GIS SE site welcomes inquiries about obtaining geographically related datasets.
Please note, however, that cross-posting is not encouraged on SE sites. Choose the best location to post your question. Later, if it proves better suited on another site, it can be migrated, along with any comments and answers. In particular, don't post a duplicate question on another SE site if your question attracts close votes; let the community moderators migrate the question for you. To aid this process, feel free to flag your own question for moderator attention.
Please look around to see if your question has been asked before. It’s also OK to ask and answer your own question.
If your question is not specifically on-topic for CrossValidated, it may be on topic for another Stack Exchange site. If no site currently exists that will accept your question, you may commit to or propose a new site at Area51, the place where new Stack Exchange communities are democratically created.