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Why does the OPM allow for distinct altern … Why does the OPM allow for distinct alternative accounts of provenance? Given that the provenenace data is meant to describe what actually occurred to produce the data, why are two alternate accounts a sensible modeling? I would think the example in Figure 5 would be better modeled as representing "add1ToAll" as being comprised of the cons/split provenance DAG, since they represent the exact same provenance, but at different levels of granularity. Is there an example where this wouldn't make sense?
The so-called "alternatives" in figure 16 might just as well be described as being two parts of the same provenance chain -- ("Execute program" triggers a procedure "Produce Sky Mosaic", etc.). However, this brings up a question as to whether processes and artifacts are disjoint. In figure 16, "Enactor Executable" is shown as an artifact, but is presumably also a process (perhaps the same process as "Produce Sky Mosaic"). How can these two paths through the provenance DAG be sensibly interpreted as alternative causality chains? Are we to conclude that the "Execute Program" alternative does not have a causal dependence on the "FITS DataSet" artifact, even though it exists in our provenance data? n though it exists in our provenance data?
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