--- a/model/working-copy/towards-wd4.html Tue Feb 07 21:48:50 2012 +0000
+++ b/model/working-copy/towards-wd4.html Tue Feb 07 21:51:22 2012 +0000
@@ -441,7 +441,7 @@
<p>Provenance reflects activities that have occurred. In some
cases, those activities reflect the execution of a plan that was
designed in advance to guide the execution. PROV-DM allows attaching
-a plan to an activity record, which represents what was intended to
+a plan to an activity, which represents what was intended to
happen. The plan can be useful for various tasks, for example to
validate the execution as represented in the provenance record, to
manage expectation failures, or to provide explanations.</p>
@@ -668,7 +668,7 @@
<p>As provenance assertions are exchanged between systems, it may be useful to add extra-information about such assertions. For instance, a "trust service" may add value-judgements about the
trustworthiness of some of the assertions made. Likewise, an interactive visualization component may want to enrich a set of provenance assertions with information helping reproduce their
-visual representation. To help with inter-operability, PROV-DM introduces a simple annotation mechanism allowing any identifiable record to be associated with notes.</p>
+visual representation. To help with inter-operability, PROV-DM introduces a simple annotation mechanism allowing anythig that is identifiable to be associated with notes.</p>
<p>A <dfn id="dfn-note">note</dfn> is a set of attribute-value pairs, whose meaning is application specific.</p>
@@ -1124,107 +1124,6 @@
</div>
-<p>An precise-1 derivation is richer than an imprecise-1 derivation, itself, being more informative that an imprecise-n derivation. Hence, the following implications
-hold.</p>
-<div class='inference' id='derivation-implications'>
-Given two entity records denoted by <span class="name">e1</span> and <span class="name">e2</span>, <span class='conditional'>if</span> the assertion <span class="name">wasDerivedFrom(e2,
-e1, a, g2, u1, attrs)</span>
- holds for some generation record identified by <span class="name">g2</span>, and usage record identified by <span class="name">u1</span>, then <span
-class="name">wasDerivedFrom(e2,e1,[prov:steps="single"] ∪ attrs)</span> also holds.<br>
-
-Given two entity records denoted by <span class="name">e1</span> and <span class="name">e2</span>, <span class='conditional'>if</span> the assertion <span class="name">wasDerivedFrom(e2,
-e1, [prov:steps="single"] ∪ attrs)</span>
- holds, then <span class="name">wasDerivedFrom(e2,e1,attrs)</span> also holds.<br>
- </div>
-
-<div class="interpretation-forward">
-For the interpretation of a derivation record, see <a href="#derivation-usage-generation-ordering">derivation-usage-generation-ordering</a> and <a
-href="#derivation-generation-generation-ordering">derivation-generation-generation-ordering</a>
-</div>
-
-<!--
-<p>
-<p>If a derivation record holds for <span class="name">e2</span> and <span class="name">e1</span>, then
-this means that the entity represented by entity record identified by <span class="name">e1</span> has an influence on the entity represented entity record identified by <span
-class="name">e2</span>,
- which at the minimum implies temporal ordering, specified as follows.
-First, we consider one-activity derivations.</p>
-
-<div class='interpretation' id='derivation-usage-generation-ordering'>Given an activity record identified by <span class="name">a</span>, entity records identified by <span
-class="name">e1</span> and <span class="name">e2</span>, generation record identified by <span class="name">g2</span>, and usage record identified by <span class="name">u1</span>, <span
-class='conditional'>if</span> the record <span class="name">wasDerivedFrom(e2,e1,a,g2,u1,attrs)</span>
-or <span class="name">wasDerivedFrom(e2,e1,[prov:steps="single"] ∪ attrs)</span> holds, <span class='conditional'>then</span>
-the following temporal constraint holds:
-the <a title="entity usage event">usage</a>
-of entity denoted by <span class="name">e1</span> <a>precedes</a> the <a title="entity generation event">generation</a> of
-the entity denoted by <span class="name">e2</span>.
-</div>
-
-<p>Then, imprecise-n derivations.</p>
-
-<div class='interpretation' id='derivation-generation-generation-ordering'>
-Given two entity records denoted by <span class="name">e1</span> and <span class="name">e2</span>, <span class='conditional'>if</span> the record <span
-class="name">wasDerivedFrom(e2,e1,[prov:steps="n"] ∪ attrs)</span>
- holds, <span class='conditional'>then</span> the following temporal constraint holds:
-the <a title="entity generation event">generation event</a> of the entity denoted by <span class="name">e1</span> <a>precedes</a> the <a title="entity generation event">generation event</a>
-of
-the entity denoted by <span class="name">e2</span>.
- </div>
-
-<p>Note that temporal ordering is between generations of <span class="name">e1</span>
-and <span class="name">e2</span>, as opposed to precise-1 derivation,
-which implies temporal ordering between the usage of <span class="name">e1</span> and
-generation of <span class="name">e2</span>. Indeed, in the case of
-imprecise-n derivation, nothing is known about the usage of <span class="name">e1</span>,
-since there is no associated activity.</p>
-
--->
-
-
-<p>The imprecise-1 derivation has the same meaning as the precise-1
- derivation, except that an activity
- is known to exist, though it does not need to be
-asserted. This is formalized by the following inference rule,
-referred to as <em>activity introduction</em>:</p>
-<div class='inference' id="activity-introduction">
-<span class='conditional'>If</span> <span class="name">wasDerivedFrom(e2,e1)</span> holds, <span class='conditional'>then</span> there exist an activity record identified by <span
-class="name">a</span>, a usage record identified by <span class="name">u</span>, and a generation record identified by <span class="name">g</span>
-such that:
-<pre class="codeexample">
-activity(a,aAttrs)
-wasGeneratedBy(g,e2,a,gAttrs)
-used(u,a,e1,uAttrs)
-</pre>
-for sets of attribute-value pairs <span class="name">gAttrs</span>, <span class="name">uAttrs</span>, and <span class="name">aAttrs</span>.
-</div>
-
-
-
-
-
-<p>
-Note that inferring derivation from usage and generation does not hold
-in general. Indeed, when a generation <span class="name">wasGeneratedBy(g, e2, a, attrs2)</span>
-<a>precedes</a> <span class="name">used(u, a, e1, attrs1)</span>, for
-some <span class="name">e1</span>, <span class="name">e2</span>, <span class="name">attrs1</span>, <span class="name">attrs2</span>, and <span class="name">a</span>, one
-cannot infer derivation <span class="name">wasDerivedFrom(e2, e1, a, g, u)</span>
-or <span class="name">wasDerivedFrom(e2,e1)</span> since
-of <span class="name">e2</span> cannot possibly be derived from
- <span class="name">e1</span>, given the creation of <span class="name">e2</span> <a>precedes</a> the use
-of <span class="name">e1</span>.
-</p>
-
-
-<p>In PROV-DM, the effective placeholder for an entity generation time is the <a>generation record</a>. The presence of
-time information in imprecise derivation records is merely a convenience notation for a timeless derivation record and a generation record with this generation time information. </p>
-
-<div class='inference' id="derivation-time-elimination">
-<span class='conditional'>If</span> <span class="name">wasDerivedFrom(e2,e1,t,attrs)</span> holds, <span class='conditional'>then</span> the following records also hold:
-<span class="name">wasDerivedFrom(e2,e1,attrs)</span> and <span class="name">wasGeneratedBy(e2,t)</span>.
-</div>
-
-
-
<div class='pending'>Should derivation have a time? Which time? This is <a href="http://www.w3.org/2011/prov/track/issues/43">ISSUE-43</a>.<em>This is now addressed in this text. Optional time in derivation is generation time. See also <a href="http://www.w3.org/2011/prov/track/issues/205">ISSUE-205</a>.</em></div>