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DDI XKOS released for public use

The DDI Alliance ( is pleased to announce the public release of XKOS version 1.2, a free and open specification that facilitates sharing and management of statistical classifications.

XKOS is a simple and elegant model to represent complex classifications via their structural and textual properties, as well as the relations between classifications. By leveraging the widely-used Simple Knowledge Organization System (SKOS), XKOS extensions allow linkages to a wealth of existing thesauri and taxonomies to better support statistical classifications and concept management systems. XKOS also refines SKOS semantic properties to allow the use of more specific relations between statistical concepts, classifications, or any other case where SKOS is employed.

XKOS is currently used at a number of national statistical agencies and has been available as a draft since 2013. Since undergoing a final review in 2017, all issues have been addressed and corrected in preparation for the publication of version 1.2.

Links to the specification and instructions for comment are found at: