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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Software-Assisted Knowledge Generation in the Archaeological Domain: A Conceptual Framework</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Patricia Martín-Rodilla</string-name>
          <email>patricia.martin-rodilla@incipit.csic.es</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Institute of Heritage Sciences. Spanish National Research Council.</institution>
          <addr-line>Santiago de Compostela</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Knowledge generation processes are traditionally related to the DIKW (data-information-knowledge-wisdom) hierarchy, a layered model for the classification of human understanding. Software components can be situated in one or several of these layers, or assist in the interfaces between two of them. Most of the knowledge generation processes that occur in the archaeology field involve complex mechanisms of abstraction, relation and interpretation. Is it possible to assist the users in performing these processes? We have detected problems in the archaeological knowledge generation process that could be improved through software assistance. We propose a conceptual framework based on the structure of the data that is being managed by the user, and on the cognitive processes that the user wishes to perform on the data. The proposed framework can, arguably, set the foundation for assisted knowledge generation implemented as software systems.</p>
      </abstract>
      <kwd-group>
        <kwd>archaeology</kwd>
        <kwd>knowledge generation</kwd>
        <kwd>software assistance</kwd>
        <kwd>conceptual modeling</kwd>
        <kwd>inference</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Archaeology is a vast domain that produces a large amount of data in different
formats: 2D and 3D images, documents, audio, video, etc. and with specific work
methodologies to record and manage data. Archaeology, like other disciplines in
humanities and social sciences, presents complex needs with regard to temporality and
subjectivity[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. In this context, researchers and archaeology professionals demand
technology support to achieve their tasks and new sub-fields emerge, such as Digital
Humanities[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], with the necessity of software systems adapted to the domain and it
characteristics.
      </p>
      <p>The strongly human-centered nature of the domain – trying to re-build past events
through existing data – focuses these needs in assisting to professionals in knowledge
generation. This complex process is the central axis and causes the rest of tasks:
conservation, preservation, museum activities, etc. However, the existing support for
knowledge generation in this domain is limited to databases applications and some ad
hoc approaches to specific data types. There is not an integral solution to assist in
knowledge generation processes.</p>
      <p>The final goal of the current doctoral research is to provide a conceptual
framework that set the foundation for assisted knowledge generation software in
archaeological domain, help the users in their cognitive processes: direct observation of the
data, complex visualizations, abstraction, etc. This paper summarizes the author’s
PhD work and project, working for one year and a half, under the supervision of Dr.
Cesar Gonzalez-Perez (Incipit, CSIC) and Prof. Oscar Pastor Lopez (Universitat
Politècnica de València). The first six months have been used for studying the
domain in a deep way.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Problem Description and Research Considerations</title>
      <p>In this section, the scope of the research is defined: a formal specification of the
problems detected and research question formulated. Also, the research methodology
followed is discussed.
2.1</p>
      <sec id="sec-2-1">
        <title>Problem statement and initial hypothesis</title>
        <p>Archaeological research builds knowledge based on data about past events. These
data are presented in different formats and have been studied for years trying to find
special characteristics and improving the recording and management efficiency.</p>
        <p>
          Existing studies identifies specific issues in the archaeological data such
temporality or subjectivity and proposes solutions to support them[
          <xref ref-type="bibr" rid="ref3">3</xref>
          ] .
        </p>
        <p>However, building archaeological knowledge is a more complex process than
supporting these data issues: it is necessary to study what the archaeologist want to do,
what questions asked to the data and how archaeologist reach the initial goals.</p>
        <p>Therefore, it is necessary to know the archaeologist’s processes in the generation
knowledge from existing data to valuable archaeological knowledge.</p>
        <p>This research tries to discover if it is possible to assist the archaeologists in the
knowledge generation processes through software. To carry out it and situate the
problem statement, a previous study has been required to detect problems and weak
points in the archaeological knowledge generation process.</p>
        <p>During five months, archaeologists have been observed in a real work environment
and have been interviewed about their work methodologies and software use. In
addition, a set of questionnaires have been elaborated in order to study deeply the
problems found during the observation period. All surveys have been completed by
archaeologists (Incipit staff and non-Incipit staff). These professionals have several
personal profiles in terms of age, gender and institutional affiliation (public/private
institution, educational/non-educational institution).</p>
        <p>The following problems in the knowledge generation process have been detected:
• Intentional use of uncertainty in the intermediate reasoning to generate knowledge.</p>
        <p>This uncertainty is not supported by existing software tools.
• Use of reasoning based on geographic and temporal data as a start point in the
knowledge generation process. However, this initial reasoning is diffused along the
rest of processes. This situation generates confusion about the context of the data in
each moment of the knowledge generation process.
• Questions asked to the data have not been tracked and specified. This situation
involves that non-asked questions are unknown and could be introduce some kind
of bias in the knowledge finally generated.
• Previous point involves, in addition, that there are no chances to share the asked
and non-asked questions between researchers or users working on the same data
sources, complicating teamwork. There is no support for the collective generation
of knowledge.
• Lack of priority management of the different questions asked to the data. (Different
level of importance has been detected in the user processes).
• Lack of abstract view of the structure of the information management in the
knowledge generation process. This problem could form the basis of a low use of
the feedback mechanism to build and ask new questions to the data based on the
responses obtained in a previous step.
• Homogeneous procedures applied to reasoning derived from direct observation and
reasoning derived for more complex mechanisms (relation between data,
abstraction, interpretation, etc.). This situation could be including confusion about the
level of the DIKW hierarchy where the reasoning is situated and the level of
subjectivity and uncertainty that is managed.</p>
        <p>The problems detected make up the problematic context of the research and the
gap founded that this research tries to fill. Our initial hypothesis is that we can
improve the knowledge generation process in the archaeological domain (minimizing or
reducing the problems detected) by building software models that reproduce and
incorporate cognitive facets and needs of the user, and allowing the application of
visualization techniques and data-pattern recognition specifically adapted to
archaeologists’ ways of working.
2.2</p>
      </sec>
      <sec id="sec-2-2">
        <title>Existing solutions</title>
        <p>
          Comparative and empirical studies have carried out to understand the
characteristics of the user, the domain and existing software solutions[
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]. However, knowledge
generation processes in archaeology are not completely supported by software, with
existing ad hoc partial solutions in terms of data[
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. Therefore, integral studies of this
topic are not found in the existing literature.
        </p>
        <p>However, there are theoretical models about human knowledge generation that
defines the corpus of this research. All existing models follow a hierarchical structure
based on layers, with other differences:</p>
        <p>
          Cleveland[
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] established a model in four layers: Fact &amp; ideas, Information,
Knowledge and Wisdom. Cleveland model laid the foundation to a human
understanding theory. The intermediate processes between layers are not characterized at
this point.
        </p>
        <p>
          Ackoff[
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] added one step more, with five layers: Data, Information, Knowledge,
understanding and Wisdom. This model has been used for several years as a reference
in psychology and cognitive studies.
        </p>
        <p>
          Carpenter &amp; Cannady[
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], based on other characterizations of the intermediate
process between layers[
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] incorporated in 2004 feedback flow between layers. They
proposed a model with six layers: Environment, Data, Information, Knowledge,
Wisdom and Vision. The intermediate steps are tagged with words that suggest cognitive
processes between layers, such as rules, goal or values.
        </p>
        <p>
          All compared models fit in with the cognitive character of the processes that allow
us to go up to the next level in the hierarchy. Thus, the characterization of these
cognitive processes into the archaeological domain could be an initial point to solve the
problems detected. Gardin[
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], Stockinger[
          <xref ref-type="bibr" rid="ref11">11</xref>
          ] or recently Doerr[
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] notes that it is
possible a formalization of these processes. However, the level of formalization of
these studies is not enough to test the hypothesis initial of this research and include it
directly in the specification of an assistance based on software solutions. It is
necessary a complete formalization to achieve this goal.
        </p>
        <p>
          Making a complete review of the literature that supports the current research, we
have reviewed the existing methods to assist through software in knowledge
generation processes in other disciplines or domains. The main example founds is the
biomedical domain, in which context Chen[
          <xref ref-type="bibr" rid="ref13">13</xref>
          ] developed a complete model to assist by
visualization software the knowledge generation process.
        </p>
        <p>
          Chen et al.[
          <xref ref-type="bibr" rid="ref13">13</xref>
          ] proposed a model based on modules incorporated to the software
system that captures the user actions, establishing how the user is generating
knowledge. The module incorporates this knowledge to the system: In the next step,
the system can adapt it behavior to the user and offer him some helped tools.
        </p>
        <p>
          Chen references DIKW[
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] as a scope of his model, without restrictions in terms of
domain. We takes into consideration this model as a basis in the archaeological
domain and adapted visualization and pattern suggestions proposed by Chen et al. as
possible output of our assisted knowledge generation system.
2.3
        </p>
      </sec>
      <sec id="sec-2-3">
        <title>Research questions and objectives</title>
        <p>
          Regarding TAR[
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] -Technical Action Research - methodologies for software and
technical research, there are two categories in terms of research questions:
        </p>
        <p>Category 1: Questions that seek an explanation for a real-world phenomenon, and
try to answer what, why or how said phenomenon occurs.</p>
        <p>Category 2: Questions that try to build some artifacts from scratch or to improve
some existing solution for a problem previously detected.</p>
        <p>The main research question of this work emerges from the initial hypothesis. It
formulation is: To what extent is it possible to improve the knowledge generation
process in archaeology by assisting the user through software tools? In order to ask
this research question, the research general goal is to test the initial hypothesis
through:
• Searching for evidence those support the hypothesis, through user testing and
empirical studies.
• Searching for evidence against the initial hypothesis, through empirical studies,
user observation, validation test and expert feedback.</p>
        <p>In the process of answering these questions, additional collateral questions are
emerging that allow us to establish a research context. Currently, the research is
focused on the secondary question: What are the major existing problems in the
knowledge generation process in archaeology? In order to answer the secondary
research question, we have defined to detect these existing problems as a specific goal
in the first part of the research.
2.4</p>
      </sec>
      <sec id="sec-2-4">
        <title>Research methodology</title>
        <p>Our research follows an established scientific methodology approach, based on an
initial hypothesis and a general research question to answer. Secondary questions are
emerging along the research process. Each secondary research question involves a set
of valuable objectives whose commitment level reflects the level of support of the
initial hypothesis. In our case, the research questions and the objectives have been
exposed in the previous section.</p>
        <p>In addition to the methodology general plan following research methods of
validation a specific methodology for the requirements elicitation and the study of
knowledge generation methods in this domain is proposed.</p>
        <p>The interdisciplinary character of the research and user characteristics has been
necessary to apply user-centered methods, in order to understand how users build
knowledge from the data and how kind of software assistance would be better to
support these processes.</p>
        <p>On the other hand, the fact that software systems are involved suggests that we
need to formalize user needs into requirements.</p>
        <p>In this scenario, a hybrid methodology is proposed. All requirement elicitation
processes are extracted following shadowing studies, interviews, surveys and user
experiments. This allows us to directly observe the users in a real work environment,
together with archaeological sets of data and case studies in their domain. In order to
contrast the empirical results in an analytical way, other analytical techniques to
extract requirements are applied concurrently, such as discourse analysis and
datamining.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Proposal</title>
      <p>Our proposal involves a conceptual framework that captures and implements the
needs of the users who work in the archaeological domain. The framework is
structured in three important parts in the knowledge generation process: data, process and
interaction.</p>
      <p>
        We have analyzed archaeological document collections from Incipit and other
open-data repositories[
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] studying the structure of the argumentation narrative,
problems in the depicted knowledge generation processes, and evidence of possible
software assistance solutions in the field. The analysis was carried by following the
discourse analysis method of Hobbs[
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], an analytical technique designed to study texts
from a linguistic perspective that allows us to characterize argumentation relations
between clauses. This method includes ten types identified as coherence relations that
include causal and contrastive argumentations, exemplifications and generalization of
arguments, etc.
      </p>
      <p>Following this method, each pair of clauses is tagged by one coherence relation.
After, the elements of the relation chosen are characterized in the clause analyzed.
Finally, it is necessary to validate the elections chosen in each analysis. In our study
the original author of each document form Incipit repositories was contacted and
asked to validate the outcome of the analysis</p>
      <p>
        The analysis results indicate that there are types of coherence relations more
common in the analyzed texts than others, namely relations based on combining values of
several attributes to build the argumentation. This type of inferences is related to
combinatory tasks, and some data-mining solutions such as rule-association
algorithms[
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] could arguably provide software assistance in the knowledge generation
process in archaeology.
      </p>
      <p>This analysis allow us to characterize in an analytical classification the
argumentation methods detected in the study, based on the objective of the user and the type of
inference that was used.</p>
      <p>The classification obtained as a result of the analysis is explained in the Figure 2,
with the corresponding mappings with Hobbs relations. It is used as basis to formalize
the cognitive processes managed by the user in archaeology.
4.2</p>
      <sec id="sec-3-1">
        <title>Empirical results</title>
        <p>Two test-sets has been designed and implemented to extract evidence of the
assisting possibilities through software in the archaeological domain.</p>
        <p>The first test contains multiple choice questions about reasoning modes in
archaeology based on real data, tasks related to knowledge generation and initial reasoning
used to process data in large datasets (See Fig.3). There are plans to publish all results
and conclusions from this test-set.</p>
        <p>
          The second test-bed includes multiple-choice questions about ten visualizations of
real archaeological data sets implemented through well-known visualizations
techniques (bars, charts, tree-maps[
          <xref ref-type="bibr" rid="ref18">18</xref>
          ], graphs, bubbles…) and different levels of
interaction. The users are asked to carry out common task against the visualized data and
must answer the questions based on direct observation, attribute value combination,
abstraction or interpretation of the data. This second test-bed is being deployed at the
time of writing with promising preliminary results.
5
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Future plan</title>
      <p>The proposed framework will be developed as an integrated metamodel covering
the three areas defined above: data, process, and interaction.</p>
      <p>
        Metamodeling the archaeological cognitive processes explained in this paper and
extracting applicable interaction primitives are our next goals. In the first case,
situational software engineering[
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] approaches are chosen to express the behaviors,
elections and objectives of the user identified in the Preliminary Results section as an
inference classification.
      </p>
      <p>In the second case, the empirical studies being carried out indicate the necessity of
different levels of interaction and visualizations, depending on the inference type
involved. We continue to work in this direction.</p>
      <p>In addition to the integrated metamodel, the implementation of a software
prototype is planned, with the objective of testing the solution and systematically analyzing
the improvements achieved in the knowledge generation process by assessing the
detected problems, their impact and the obstacles encountered.</p>
    </sec>
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