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ADL Experience API (xAPI) and IMS Caliper Discovery Review

July 25, 2016

As many of you know, there have been ongoing efforts over the years to investigate the readiness of the Experience API (xAPI) for eventual standardization.  In the past, this included splitting the core specification into more modular documents, facilitating conversations with standards organizations, and thinking about a new transition strategy for long-term sustainability. More recently, we began the process to update DoD policy and are actively investing in the creation of conformance testing and certification processes and capabilities for xAPI.

As xAPI has matured, so too has a similar specification from the IMS Global Learning Consortium called Caliper.  There are notable similarities between xAPI and Caliper, which has caused adopters and vendors to clarify implementation differences of one or both specifications (both of which are now targeting standardization). Both communities supporting xAPI and Caliper have expressed concerns about being able to cost-effectively support both specs, which led to inquiries to both ADL Initiative and IMS about whether alignment of the two would be possible.

ADL Initiative recently joined the IMS as a contributing member. Both organizations have expressed a renewed interest to work together and collaborate on learning technology standards and research areas of mutual interest. ADL Initiative and IMS also recently began discussions about the possibility of aligning the specs and whether it is even practical or achievable. We decided these things can't be determined and the work can't be done without harnessing the collective expertise and wisdom of both xAPI and Caliper communities.

A possible xAPI and Caliper public collaboration project would be driven technically, not politically, meaning that the final outcome will be based on how much harmonization, if any, can be accomplished between the two specs.  A wide spectrum of possible value-added outcomes are provided below

  1. Clear messaging, agreed upon by both communities of when to use Caliper and when to use xAPI
  2. Identify the differences and similarities between xAPI vocabularies, profiles, and recipes compared to the Caliper information model and metric profiles. Determine if alignment is possible.
  3. Determine if it technically possible to harmonize both specifications based on data formats, security, privacy, transport mechanisms, etc.
  4. Determine if it is semantically possible to harmonize the specs to "sound" more like each other with agreed upon terminology.
  5. Determine if  convergence into one specification and eventually, a standard is possible, and if not then if a crosswalk of data models a suitable option.

In order to gauge the perspectives and interest of both xAPI and Caliper communities, we've developed a survey.  Please complete this survey to help shape our collaboration efforts and increase our collective awareness.

ADL Initiative will be participating in the IMS Quarterly meeting from August 15-18. On August 15th, there will be a day long meeting in support of a xAPI/ Caliper Discovery Review. This meeting will work to start exploring the differences in xAPI and Caliper.  IMS Members and the Public may attend.  This will be a working meeting and those with experience in xAPI and/or Caliper are encouraged to join us. This meeting is a kickoff to future collaborative efforts which will include virtual participation.

As with all of our efforts, we want to maintain transparency and openness in development of specifications, standards, and software.  Please complete the survey and consider joining us on August 15th! Thank you for all of your support.