Validation - validate the generated turtle representation, both for assertions and evidence and provenance aka validate knowledge graphs

[tekrajchhetri]

No description provided.

[tekrajchhetri]

The knowledge graph validation milestone is to ensure the structural integrity, semantic accuracy, and consistency of a knowledge graph. This involves checking that the graph adheres to predefined schemas or ontologies, verifying relationships and entities, and validating data completeness. As there's always a question to what we should called complete, by completeness we refer to the presence of the necessary information, which in our case is the assertion, evidence, and the provenance information about the assertion and evidence.

One way to perform the validation is using SHACL shapes. Below is an example of the SHACL shape to validate the hasSimpleResult, which is a property associated with Observation class.

You can read the below SHACL as follows, sosa:hasSimpleResult should have exactly 1 value. The value can be between 0-100 (inclusive). It is part of the Observation class.

Example input:

we can read the following input as DHT11 is a sensor which made observation at Senseinlab_temperature, i.e., the tempreature is measured at time 2024-11-26T21200:01 and the observation result has a unit of percent.

<someID> a sosa:Observation ;
                om:hasUnit om:percent ; //we explicitly state they type of unit or the formal semantics -- this is something that distinguishes KG from normal graph
                sosa:hasSimpleResult 2.2e+02 ;
                sosa:madeBySensor <http://www.w3.org/ns/sosa/Sensor/DHT11> ;
                sosa:observedProperty <http://www.w3.org/ns/sosa/observedProperty/Senseinlab_temperature> ;
                sosa:resultTime "2024-11-26T21200:01"^^xsd:dateTime .

            <http://www.w3.org/ns/sosa/Sensor/DHT11> a sosa:Sensor ;
                sosa:observes <http://www.w3.org/ns/sosa/Observation/DHT11_11> .

Though the above example is not directly associated with assertion/evidence, it should give a sense of what SHACL looks like. Also, it is important to highlight that just SHACL based validation might not be enough.