- From: Dave Reynolds <der@hplb.hpl.hp.com>
- Date: Tue, 02 May 2006 14:45:29 +0100
- To: Paula-Lavinia Patranjan <paula.patranjan@ifi.lmu.de>
- CC: public-rif-wg@w3.org
Paula-Lavinia Patranjan wrote: > Hi, > > Based on the design constraints, which have been proposed by some of the > RIF participants, and the previous work on requirements, a new, refined > version for the hierarchy of design constraints is proposed: > > http://www.w3.org/2005/rules/wg/wiki/Towards_a_Rule_Interchange_Format%3A_Goals%2C_Critical_Success_Factors%2C_Requirements > > > This draft is work in progress and its aim is to raise discussions that > will entail decisions on RIF's goals, critical success factors and > requirements; I will refine this draft based on your feedback. Short > comments and comparison to Dave's proposal (cf. > http://lists.w3.org/Archives/Public/public-rif-wg/2006Apr/0005) for a > hierarchy of same kind are also stated. Thanks very much for this, I have three non-trivial comments and a few minor questions/quibbles. First, this seems to focus on maximizing expressivity. There are a lot of requirements in here covering everything from probabilistic reasoning, to courteous logic to FOL. I don't see anything aimed at narrowing the scope to improve cohesion. For effective interchange there has to be some encouragement to moderate the expressivity of individual dialect to increase the chances of there being reasonably complete implementations of a given dialect. Second, I don't see much in here which connects RIF to the web other than the requirement to ingest XML/RDF/OWL. There is no requirement for webization (URIs and all that), no requirement for external access to web data sources (e.g. SPARQL), no overall goal expressed towards make RIF relevant towards rule use on the semantic web. Third, the top level division into goals isn't quite intuitive for me. I'm not sure whether this is simply a matter of phrasing to make them read more like goals or whether there is a structural problem here or whether it's just me. For example, 1.3.4 (probabilistic information on propositions) I would have expected to see related to expressivity rather than data sources. I would have thought semantics was needed achieve the interchange goal and don't quite understand why it's a separate goal rather than a CSF for the rule exchange goal. Minor questions/comments: o A final version presumably will distinguish between the phases 1/2/n. o 1.2 RIF rules are made of RIF component languages ... Not clear what that means. Is it really a CSF? Seems more like a solution we may or may not have chosen than a critical success factor. o 1.3.4 Support degrees of truth ... That needs more debate. o 1.4.4 Meta rules for meta reasoning ... This needs rather more definition but is in any case out of place in "Inexpensive representation of rules", it seems more like part of expressivity. o 2.1.1 Format for specifying the intended interpretation (semantics interchange format) There is a requirement that the semantics intended for a given rule set be clear but not necessarily for a separate "semantics interchange format". Up until now we've talked about some form of metadata tags to indicate the semantics intended and I've presumed that those semantics would be defined in separate (standard) documents and are not themselves directly exchanged. Is this requirement really calling for an interchange format for semantics? o 2.2.1 Definition of default behavior(s) Not happy with this one but that's because I don't understand what Christian is trying to express here. To me this should be part of the specification of the relevant RIF language construct, not something that "RIF must carry" (which implies per-rule or per-ruleset behaviour). Furthermore, I struggle see cases there are where there can be a behaviour other than "IGNORE_RULESET". Dave
Received on Tuesday, 2 May 2006 13:45:57 UTC