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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Intelligence Analysis Ontology for Cognitive Assistants</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Mihai Boicu</string-name>
          <email>mboicu@gmu.edu</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gheorghe Tecuci</string-name>
          <email>tecuci@gmu.edu</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>David Schum</string-name>
          <email>dschum@gmu.edu</email>
        </contrib>
      </contrib-group>
      <abstract>
        <p>-This paper presents results on developing a general intelligence analysis ontology which is part of the knowledge base of Disciple-LTA, a unique and complex cognitive assistant for evidence-based hypothesis analysis that helps an intelligence analyst cope with many of the complexities of intelligence analysis. It introduces the cognitive assistant and overviews the various roles and the main components of the ontology: an ontology of “substance-blind” classes of items of evidence, an ontology of believability analysis credentials, and an ontology of actions involved in the chains of custody of the items of evidence.</p>
      </abstract>
      <kwd-group>
        <kwd>cognitive assistant</kwd>
        <kwd>ontology</kwd>
        <kwd>evidence-based hypothesis analysis</kwd>
        <kwd>types of items of evidence</kwd>
        <kwd>chains of custody</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. THE COMPLEXITY OF INTELLIGENCE ANALYSIS</title>
      <p>
        Intelligence analysts face the difficult task of analyzing
masses of information of different forms and from a variety
of sources. Arguments, often stunningly complex, are
necessary in order to link evidence to the hypotheses being
considered. These arguments have to establish the three major
credentials of evidence: its relevance, credibility, and
inferential force or weight. Relevance considerations answer
the question: So what? How does this item of information bear
on any hypothesis being considered? Credibility
considerations answer the question: Can we believe what this
item of information is telling us? Inferential force or weight
considerations answer the question: How strongly does this
item of evidence favor or disfavor alternative hypotheses we
are considering? Establishing these three evidence credentials
always involves mixtures of imaginative and critical
reasoning. Indeed, as work on an analytic problem proceeds,
we commonly have evidence in search of hypotheses at the
same time with hypotheses in search of evidence. First, various
hypotheses and lines of inquiry must be generated by analysts
who imagine possible explanations for the continuous
occurrence of events in our non-stationary world. Second,
considerable imagination is required in decisions about what
items of information should be considered in the analytic
problem at hand. But critical reasoning in intelligence analysis
is equally important. No item of evidence comes with its
relevance, credibility, and inferential force or weight
credentials already established. These credentials must be
established by defensible and persuasive arguments which
have to take into account that our evidence is always
incomplete, usually inconclusive, frequently ambiguous,
commonly dissonant, and it comes to us from sources having
any gradation of credibility shy of perfection [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
      </p>
      <p>But the inherent complexity of the analysts' tasks are only
part of their problems. In many cases, analysts are not given
unlimited time to generate hypotheses and evidence and to
construct elaborated and careful arguments on all elements of
the analysis at hand. One way of describing this problem is to
say that analysts will neither have the time, or the necessary
evidential basis, for drilling down or decomposing all elements
of the problem being considered. In many instances, analysts
are faced with the necessity of having to make various
assumptions in which certain events are believed "as if" they
actually occurred. And always, the world is evolving and the
yesterday’s analysis needs to be updated with new items of
evidence discovered today.</p>
    </sec>
    <sec id="sec-2">
      <title>II. DISCIPLE-LTA: ANALYST’S COGNITIVE ASSISTANT</title>
      <p>
        Disciple-LTA is a unique and complex analytic tool that can
help an intelligence analyst cope with many of the
complexities of intelligence analysis [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. The name
Disciple, by itself, suggests that it learns about intelligence
analysis through its interaction with experienced intelligence
analysts. The word "disciple" has synonyms including: learner,
advocate, supporter, and proponent. The addition "LTA",
refers to the fact that Disciple learns analysis [L], it can serve
as a tutor [T] for novice and experienced analysts, and it can
assist [A] in the performance of analytic tasks, e.g. in current
or in finished intelligence analyses. Disciple-LTA has two very
distinct differences from other knowledge-based or rule-based
"expert systems" developed in the field of artificial
intelligence over the years. Such systems are developed by
knowledge engineers who attempt to capture and represent the
heuristics or rules of the experienced expert users so that they
could be preserved and utilized in new situations. This is a
very long and difficult process that results in systems that are
even more difficult to maintain. But Disciple-LTA is
qualitatively different from these earlier expert systems.
      </p>
      <p>Instead of being programmed by a knowledge engineer,
Disciple-LTA learns its expertise directly from expert analysts
who can teach it in a way that is similar to how they would
teach a person. However, when it is first used by an expert
analyst, Disciple-LTA does not engage in this interaction with
a blank mental tablet. Disciple-LTA already has a stock of
established knowledge about evidence, its properties, uses, and
discovery. Some of this knowledge may not be already
resident in the minds of its expert users, who apply their
experience with certain analytic contexts that Disciple will
learn. So, Disciple does learn about specific intelligence
problems from its users, but it can combine this knowledge
with what it already knows about various elements of
evidential reasoning. Conventional expert systems can be no
better than the expertise of the persons whose heuristics are
trapped; this represents a "ceiling" on the suitability of these
earlier systems. But this ceiling is actually the "floor" for
Disciple-LTA, since this system incorporates basic knowledge
of the evidential reasoning tasks analysts face in addition to the
substantive expertise of the analysts who interact with it.</p>
      <p>One basic feature of Disciple-LTA is that it provides the
analyst the opportunity to decompose a complex problem into
finer levels; i.e. it rests upon a "divide and conquer" strategy
for dealing with the analytic complexity of hypothesis in
search of evidence. In particular, it allows "top-down"
decompositions to deduce from a stated hypothesis what needs
to be proven in order to sustain this hypothesis. This
decomposition eventually results in the identification of
possible sources of evidence relevant to this hypothesis.
Consider, for example, the problem of assessing whether Al
Qaeda has nuclear weapons. This problem can be reduced to
three simpler problems of assessing whether Al Qaeda has
reasons, has desires, and has ability to obtain nuclear weapons.
Each of these simpler problems is further reduced to even
simpler ones (e.g. by considering specific reasons, such as
deterrence, self-defense, or spectacular operation) that could
be solved either based on the available knowledge or by
analyzing relevant items of evidence. An abstraction of these
decompositions is presented in the left-hand side of Fig. 1. Let
us consider “Spectacular operation as reason” which is a short
name for “Assess whether Al Qaeda considers the use of
nuclear weapons in spectacular operations as a reason to
obtain nuclear weapons.” As indicated in the left-hand side of
Fig. 1, to solve this hypothesis analysis problem Disciple-LTA
considered both favoring evidence and disfavoring evidence.
Disciple-LTA has found two items of favoring evidence,
EVDFP-Glazov01-01c and EVD-WP-Allison01-01, and it has
analyzed to what extend each of them favors the hypothesis
that Al Qaeda considers the use of nuclear weapons in
spectacular operations as a reason to obtain nuclear weapons.</p>
      <p>EVD-FP-Glazov01-01c is shown in the bottom right of Fig. 1.</p>
      <sec id="sec-2-1">
        <title>Detailed evidence and source analysis</title>
      </sec>
      <sec id="sec-2-2">
        <title>EVD-FP-Glazov01-01c</title>
        <p>
          It is a fragment from a magazine article published in the Front
Page Magazine by Glazov J. where he cites Treverton G. who
stated that Al Qaeda may perform a spectacular nuclear attack
against United States [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]. To analyze EVD-FP-Glazov01-01c,
Disciple-LTA considered both its relevance and its
believability [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ], [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. The believability of
EVD-FP-Glazov0101c depends both on the believability of Glazov J. (the
reporter of this piece of information) and the believability of
Treverton G. (the source). The believability of the source
depends on his competence and his credibility. The credibility
of Treverton G. depends on his veracity, objectivity, and
analytical ability. When the analyst clicks on a problem, such
as “Credibility” from the left-hand side of Fig. 1,
DiscipleLTA displays the details on how it solved that problem, as
shown in the right-hand side of Fig. 1. For example, to “Assess
the credibility of Treverton G as the source of
EVD-FPGlazov01-01c” Disciple-LTA has assessed his veracity,
objectivity, and analytical ability. Then the results of these
assessments (almost certain, almost certain and almost certain)
have been combined into an assessment of the credibility
(almost certain). Disciple-LTA may use different synthesis
functions for the solutions (such as, minimum, maximum,
average, etc.), depending on the types of the problems. A
abstraction of the synthesis process is displayed in the left
hand side of Fig. 1, where the solutions appear in green,
attached to the corresponding problems. Notice that this
problem-reduction/solution-synthesis approach enables a
natural integration of logic and probability.
        </p>
        <p>
          In some situations the analysts will not have the time to deal
with all of the complexities their own experience and
DiscipleLTA makes evident. In other situations, analysts will not have
access to the kinds of information necessary to answer all
questions regarding elements of an analysis that seem
necessary. In such situations Disciple-LTA allows the user to
decompose (“to drill down”) an analysis to different levels of
refinement in order to reach conclusions about necessary
analytic ingredients, by providing mechanisms necessary to
identify assumptions that are being made and by showing the
extent to which conclusions rest upon these assumptions [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ].
        </p>
        <p>For evidence in search of hypotheses, Disciple-LTA allows
the construction of "bottom-up" structures in which possible
alternative hypotheses are generated. No computer system,
even Disciple-LTA, is capable of the imaginative thought
required to generate hypotheses and new line of inquiry. But
Disciple-LTA can assist in this process by prompting the
analyst to consider the inferential consequences of chains of
thought that occur in the process of generating hypotheses and
new lines of inquiry and evidence.</p>
        <p>The following sections will discuss the general features of
the intelligence analysis ontology of Disciple-LTA.
III. KNOWLEDGE BASE STRUCTURE FOR SHARING AND REUSE</p>
        <p>In addition to the separation of knowledge and control
(which is a characteristic of all the knowledge-based systems),
Disciple-LTA is characterized by an additional architectural
separation at the level of the knowledge base. Its knowledge
base is structured into an object ontology that defines the
concepts of the application domain, and a set of problem
solving rules expressed in terms of these concepts. While an
ontology is characteristic to an entire domain (such as
intelligence analysis), the rules are much more specific,
corresponding to a certain type of applications in that domain,
and even to specific subject matter experts. This separation
allows one to easily share and reuse the ontology developed
for a given intelligence analysis application, when developing
a new one. Additionally, the ontology in Disciple-LTA is
organized as a distributed hierarchy of several ontologies,
which further facilitate its sharing and reuse, as well as its
development and maintenance.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>IV. MULTIPLE ROLES FOR ONTOLOGY</title>
      <p>
        The object ontology plays a crucial role in Disciple-LTA
and in cognitive assistants, in general, being at the basis of
knowledge representation, user-agent communication, problem
solving, knowledge acquisition and learning [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. First, the
object ontology provides the basic representational
constituents for all the elements of the knowledge base,
including the problems, the problem reduction rules, and the
solution synthesis rules. The ontology language of
DiscipleLTA is an extension of OWL-light [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] that allows the
representation of partially learned concepts and features. A
partially learned feature may have both it domain and its range
represented as plausible version space concepts [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. One may
also define different symbolic probability scales, such as Kent,
DNI, IPCC or legal [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], and automatically convert from one to
another and into the Bayesian probabilities. For example, the
left hand side of Fig. 2 shows the symbolic probabilities for
likelihood, based on the DNI’s standard estimative language,
while the right hand side
shows the corresponding
Bayesian probability
intervals. The ontology
also allows the
representation of items of
evidence that may contain
different or even
contradictory views on
some entities. Fig. 2. Symbolic probabilities for likelihood.
      </p>
      <p>
        Second, the agent’s ontology enables the agent to
communicate with the user and with other agents by declaring
the terms that the agent understands. As illustrated in the
upper-right part of Fig. 1, the agent uses natural language
phrases where the terms from the ontology appear in blue.
Consequently, the ontology enables knowledge sharing and
reuse among agents that share a common vocabulary which
they understand. Third, the problem solving rules of the agent
are applied by matching them against the current state of the
agent’s world which is represented in the ontology. The use of
partially learned knowledge (with plausible version spaces) in
reasoning, allows solving of problems with different degrees of
confidence [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Fourth, the object ontology represents the
generalization hierarchy for learning, general rules being
learned from specific problem solving examples by traversing
this hierarchy [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
    </sec>
    <sec id="sec-4">
      <title>V. ONTOLOGY OF “SUBSTANCE-BLIND” CLASSES</title>
      <p>OF ITEMS OF EVIDENCE</p>
      <p>Being able to categorize evidence is vitally necessary for
many reasons, one of the most important being that we must
ask different questions of and about our evidence in the
process of intelligence analysis in which we encounter
different recurrent forms and combinations of evidence. If we
were not able to categorize evidence in useful ways we might
not be aware of many different questions we should be asking
of our evidence. However, asked to say how many kinds of
evidence there are, we could easily say that there is near
infinite amount, if we considered its substance or content. This
presents a significant problem: how can we ever say anything
general about evidence if every item of it is different from
every other item? Fortunately there is a "substance-blind" way
of categorizing evidence that does not rely at all on its
substance or content, but on its inferential properties: its
relevance and believability.</p>
      <p>
        Disciple-LTA includes an ontology of “substance-blind”
classes of items of evidence. Some of the classes based on
their believability attributes are shown in Fig. 3 [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
      </p>
      <p>If you can pick up the evidence yourself and examine it to
see what events it might reveal, we say the evidence is tangible
in nature such as objects, documents, images, and tables of
measurements. We distinguish between real tangible evidence
which is an actual thing itself (such as a captured weapon
component), and demonstrative tangible evidence, which is a
representation or illustration of this thing (such as a diagram of
that component). Now suppose you have nothing you can
examine for yourself and must rely on someone else who has
made some observation and who will tell you about the
occurrence or nonoccurrence of some event. This is called
testimonial evidence, as in a HUMINT report from an asset.
This person may state unequivocally that some event has
occurred or has not occurred. Of great concern is how the
person providing testimonial evidence obtained the
information reported. Did this person make a direct
observaton or did he/she learn about the occurrence or
nonoccurrence of the reported event from another person, in
which case we have secondhand or hearsay evidence.
Moreover, there are classes of evidence mixtures, such as
testimonial evidence about tangible evidence. It would not be
uncommon in intelligence analysis to encounter evidence
obtained through a chain of sources (see section VII).</p>
      <p>
        VI. ONTOLOGY OF BELIEVABILITY ANALYSIS CREDENTIALS
As discussed above, the “substance-blind” ontology of
classes of evidence is based on their believability and
relevance credentials. That is, there are specific credentials for
each such class. For example, the believability of a source of
direct testimonial evidence depends on the source’s
competence and credibility [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Assessments of the
competence of a source require answers to two important
questions. First, did this source have access to, or did actually
observe, the events being reported? If it is believed that a
source did not have access to, or did not actually observe the
events being reported, we have very strong grounds for
suspecting that this source fabricated this report or was
instructed what to tell us. Second, we must have assurance that
the source understood the events being observed well enough
to provide us with an intelligible account of these events. So,
access and understanding are the two major attributes of a
human source's competence. Assessments of human source
credibility require consideration of entirely different attributes:
veracity (or truthfulness), objectivity, and observational
sensitivity under the conditions of observation. Here is an
account of why these are the major attributes of testimonial
credibility. First, is this source telling us about an event he/she
believes to have occurred? This source would be untruthful if
he/she did not believe the reported event actually occurred. So,
this question involves the source's veracity. The second
question involves the source's objectivity. The question is: did
this source base a belief on sensory evidence received during
an observation, or did this source believe the reported event
occurred either because this source expected or wished it to
occur? An objective observer is one who bases a belief on the
basis of sensory evidence instead of desires or expectations.
Finally, if the source did base a belief on sensory evidence,
how good was this evidence? This involves information about
the source's relevant sensory capabilities and the conditions
under which a relevant observation was made.
      </p>
      <p>Answers to these competence and credibility questions
require information about our human sources. But one thing is
abundantly clear: the competence and credibility of HUMINT
sources are entirely distinct. Competence does not entail
credibility, nor does credibility entail competence. Confusing
these two characteristics invites inferential disaster Error!
Reference source not found.. Disciple-LTA includes an
ontology of these credentials and Fig. 1 shows an example of
using such credentials in analyzing the believability of an item
of evidence.</p>
    </sec>
    <sec id="sec-5">
      <title>VII. ONTOLOGY OF ACTIONS FROM CHAINS OF CUSTODY</title>
      <p>A crucial step in answering questions on the believability of
the items of evidence involves having knowledge about the
chain of custody through which the testimonial or tangible
item has passed en route to the analyst who is charged with
assessing it. Basically, establishing a chain of custody involves
identifying the persons and devices involved in the acquisition,
processing, examination, interpretation, and transfer of
ontology of actions that may be involved in a wide variety of
chains of custody for different types of evidence, such as
HUMINT, IMINT, SIGINT or TECHINT. For example, Fig. 5
shows the representation of a translation action. The
believability of this translation depends both on the translator’s
competence (in the two languages, as well as the subject matter
being translated) and on his/her credibility.</p>
      <p>Fig. 4. Evaluating the believability of an item of evidence obtained through a chain of custody.
evidence between the time the evidence is acquired and the
time it is provided to intelligence analysts. Lots of things may
have been done to evidence in a chain of custody that may
have altered the original item of evidence, or have provided an
inaccurate or incomplete account of it. In some cases original
evidence may have been tampered with in various ways, the
analysts risking of drawing quite erroneous conclusions from
the evidence they receive. Suppose we have an analyst who is
provided with an item of testimonial evidence by an informant
who speaks only in a foreign language. We assume that this
informant's original testimony is first recorded by one of our
intelligence professionals; it is then translated into English by
a paid translator. This translation is then edited by another
intelligence professional; and then the edited version of this
translation is transmitted to an intelligence analyst. So, there
are four links in this conjectural chain of custody of this
original testimonial item: recording, translation, editing, and
transmission. Various things can happen at each one of these
links that can prevent the analyst from having an authentic
account of what our source originally provided. Fig. 4 shows
how the believability of the testimonial evidence provided to
the analyst (EVD-Wallflower-5) depends on the believability
of the testimony of the informant (i.e. EVD-Wallflower-1), but
also on the believability of the Recording, Translation,
Editing, and Transmission actions. Disciple-LTA has an</p>
    </sec>
    <sec id="sec-6">
      <title>VIII. LESSONS AND STORIES ABOUT</title>
      <p>INTELLIGENCE ANALYSIS CONCEPTS</p>
      <p>
        Disciple-LTA can be used to helps new
intelligence analysts learn the reasoning
processes involved in making intelligence
judgments and solving intelligence analysis
problems. In particular, its ontology includes
lessons and stories about a wide range of
intelligence analysis concepts, such as the
lesson on veracity illustrated in Fig. 6 [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
Moreover, its stock of established knowledge
about evidence, its properties, uses, and
discovery, makes it a suitable educational tool
even for expert analysts.
      </p>
    </sec>
  </body>
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</article>