5 ★ Open Data

Tim Berners-Lee, the inventor of the Web and Linked Data initiator, suggested a 5 star deployment scheme for Open Data. Here, we give examples for each step of the stars and explain costs and benefits that come along with it.

5-star steps by example

By Example ...

Below, we provide examples for each level of Tim's 5 star Open Data plan. The example data used throughout is 'the temperature forecast for Galway, Ireland for the next 3 days':

make your stuff available on the Web (whatever format) under an open license1 example ...
★★ make it available as structured data (e.g., Excel instead of image scan of a table)2 example ...
★★★ use non-proprietary formats (e.g., CSV instead of Excel)3 example ...
★★★★ use URIs to denote things, so that people can point at your stuff4 example ...
★★★★★ link your data to other data to provide context5 example ...

Costs & Benefits ...

What are the costs & benefits of Web data?

As a consumer ...

As a publisher ...

It's great to have the data accessible on the Web under an open license (such as PDDL, ODC-by or CC0), however, the data is locked-up in a document. Other than writing a custom scraper, it's hard to get the data out of the document.

What are the costs & benefits of ★★ Web data?

As a consumer, you can do all what you can do with Web data and additionally:

As a publisher ...

Splendid! The data is accessible on the Web in a structured way (that is, machine-readable), however, the data is still locked-up in a document. To get the data out of the document you depend on proprietary software.

What are the costs & benefits of ★★★ Web data?

As a consumer, you can do all what you can do with ★★ Web data and additionally:

As a publisher ...

Excellent! The data is not only available via the Web but now everyone can use the data easily. On the other hand, it's still data on the Web and not data in the Web.

What are the costs & benefits of ★★★★ Web data?

As a consumer, you can do all what you can do with ★★★ Web data and additionally:

As a publisher ...

Wonderful! Now it's data in the Web. The (most important) data items have a URI and can be shared on the Web. A native way to represent the data is using RDF, however other formats such as Atom can be converted/mapped, if required.

What are the costs & benefits of ★★★★★ Web data?

As a consumer, you can do all what you can do with ★★★★ Web data and additionally:

As a publisher ...

Brilliant! Now it's data, in the Web linked to other data. Both the consumer and the publisher benefit from the network effect.

See Also

Kudos to Andy Seaborne for pointing out the CSV bug, to Kerstin Forsberg for suggesting the 'data highlighting' in the 4/5 star examples, as well as to Vassilios Peristeras for proposing to explain not only the 'what' but also the 'why'. Thanks to Egon Willighagen for providing more details about benefits of one-star data. Additional contributions from Christopher Gutteridge. This site is brought to you by the EC FP7 Support Action LOD-Around-The-Clock (LATC).