# Locating freely available data samples

I've been working on a new method for analyzing and parsing datasets to identify and isolate subgroups of a population without foreknowledge of any subgroup's characteristics. While the method works well enough with artificial data samples (i.e. datasets created specifically for the purpose of identifying and segregating subsets of the population), I'd like to try testing it with live data.

What I'm looking for is a freely available (i.e. non-confidential, non-proprietary) data source. Preferably one containing bimodal or multimodal distributions or being obviously comprised of multiple subsets that cannot be easily pulled apart via traditional means. Where would I go to find such information?

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This should be community-wiki. –  mbq Jul 19 '10 at 22:31
I didn't even see that checkbox. Done :-) –  EAMann Jul 20 '10 at 20:51
You might like getthedata.org a question and answer site dedicated to finding data sets –  Jeromy Anglim Feb 21 '11 at 7:02

Also see the UCI machine learning Data Repository.

http://archive.ics.uci.edu/ml/

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also the US census data census.gov/main/www/access.html –  Stephen Turner Jul 19 '10 at 19:25

See my response to "Datasets for Running Statistical Analysis on" in reference to datasets in R.

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you should copy that here before it gets deleted... –  naught101 Nov 21 '12 at 7:34

World Bank offers quite a lot of interesting data and has been recently very active in developing nice API for it.

Also, commugrate project has an interesting list available.

For US health related data head for Health Indicators Warehouse.

Daniel Lemire's blog points to few interesting examples (mostly tailored towards DB research) including Canadian Census 1880 and synoptic cloud reports.

And as for today (03/04/2012) US 1940 census records are also available to download.

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The World Bank is going the extra mile with open data and maps, for Stata and R. –  Fr. Mar 18 '12 at 16:02

Gapminder has a number (430 at the last look) of datasets, which may or may not be of use to you.

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MLComp has quite a few interesting datasets, and as a bonus your algorithm will get ranked if you upload it.

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Start R and type data(). This will show all datasets in the search path. Many additional datasets are available in add-on packages. For example, there are some interesting real-world social science datasets in the AER package.

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http://www.reddit.com/r/datasets and also, http://www.reddit.com/r/opendata both contain a constantly growing list of pointers to various datasets.

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Timetric provides a web interface to data and provide a list of the publicly available data sets they use

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This is probably the most complete list you'll find: Some Datasets Available on the Web

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Adding a couple to the list:

Both available via a REST API and have free trial plans.

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Peter Skomoroch maintains a list of datasets at http://www.datawrangling.com/some-datasets-available-on-the-web. Many of the links provided as to places that list datasets.

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Data sets from seminal book A handbook of small data sets are available here.

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Usage Over Time

http://pewinternet.org/Trend-Data/Usage-Over-Time.aspx

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http://www.ckan.net has a number of datasets too.

http://www.biotorrents.net/browse.php is also starting to have quite a large amount of BIG datasets.

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