Review Comment:
This manuscript has been evaluated based on the comments raised in the previous round of reviews.
Overall, the authors have addressed most of the major comments. In particular, the concerns about the SPARQL templates, the S-Path views, and the readability of the plots have been resolved by the authors. Nonetheless, below I describe some issues that are still open and I hope the authors can address in the next version of the manuscript.
# Major issue: Formal definition of semantic paths
The definition of semantic paths is presented using triple patterns. Yet, this formalisation is rather ambiguous as it is difficult to see what the assumptions are and what conditions are fulfilled by the entities or resources that belong to the same semantic path. For example, in the triple pattern (?entities p1/p2/.../pn ?values), is it correct to assume that p1/p2/.../pn is a constant? In other words, is p1/p2/.../pn given?
The triple pattern characterising the similarity of the entities in the semantic path is rather ambiguous. Please note that the triple pattern (?entities rdf:type ?typeURI) indicates that every resource must be associated with *some* class. However, the value of ?typeURI is not necessarily the same class for all the resources in ?entities. This would make the definition incorrect as, in my understanding, all the entities in the semantic path should belong to the same class.
An alternative formalisation that mitigates these issues is suggested below using set notation. In my opinion, since semantic paths are set of resources it is more natural to formalise this concept using sets. I would suggest the authors to carefully check this suggestion to ensure that it correctly captures the notion of semantic paths.
Given an RDF graph and a set of URIS p1,p2,...,pn, with n>=1. A semantic path is a set of resources P = { e | (e p1/p2/.../pn o) \in G for some o \in (U \cup L)} such that \forall e_1, e_2 \in P \exists C \in U, \e_1 rdf:type C and \e_2 rdf:type C.
Note: U and L are the set of URIs and literals, respectively, as used in the literature to define RDF terms.
# Minor comments
- "A semantic path is a set of resources related to a set of values by a sequence of RDF statements" -> RDF predicates. Please note that 'RDF statement' is used to refer to an 'RDF triple'.
- Fig 1., why is the query performed recursively? Maybe the authors meant that the query is split into other queries, whose results are then combined to answer the original query. Please note that this process is not necessarily recursive but rather a "Divide-and-Conquer" approach.
- Fig1., datatype(VALUES) should be datatype(?values). Please check.
- Page 6, line 32 (second column), 1.11-12 should be 11-12. Please check.
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