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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Understanding Trends in the Patent Domain</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Julia M. Struß</string-name>
          <email>julia.struss@uni-</email>
          <email>julia.struss@unihildesheim.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thomas Mandl</string-name>
          <email>mandl@uni-</email>
          <email>mandl@unihildesheim.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Christa Womser-Hacker</string-name>
          <email>womser@uni-</email>
          <email>womser@unihildesheim.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michael Schwantner</string-name>
          <email>michael.schwantner@fizkarlsruhe.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>FIZ Karlsruhe - Leibniz, Institute for Information</institution>
          ,
          <addr-line>Infrastructure, Hermann-von-HelmholtzPlatz 1, 76344 EggensteinLeopoldshafen</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Hildesheim, Institute for Information</institution>
          ,
          <addr-line>Science and Natural, Language Processing, Marienburger Platz 22, 31141 Hildesheim</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2014</year>
      </pub-date>
      <fpage>8</fpage>
      <lpage>10</lpage>
      <abstract>
        <p>The proceeding globalization in combination with an increasing competition in research conducted at universities and other research institutes as well as in industry, emphasises the necessity of identifying trends at an early stage, not only in industry but by universities and governments. One of the resources to be considered are patents, as most of the information contained therein is not published anywhere else. The existing research focuses on the technical perspective of identifying trends in patents. This work addresses the user perspective of the problem, in particular the user's working environments, understanding of trends, the underlying tasks and the user requirements regarding a trend mining system are examined.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;trend mining on patents</kwd>
        <kwd>requirement analysis</kwd>
        <kwd>semi-structured interviews</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Categories and Subject Descriptors</title>
      <p>D.2.1 [Software Engineering]: Requirements/Speci cations;
H.1.2 [Models and Principles]: User/Machine Systems|
Human factors</p>
    </sec>
    <sec id="sec-2">
      <title>1. INTRODUCTION</title>
      <p>
        The increasing competition in research conducted at
universities and other research institutes as well as in industry,
further intensi ed by the increasing globalization, reinforces
the importance of identifying new trends at an early stage.
According to a study by Thomson Reuters [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], 70% to 90%
of the information covered in patents { depending on the
research area { is not published anywhere else. The growth
of this huge information resource in terms of led patents is
also increasing faster every year: According to the annual
report of the European Patent O ce in 2012 new records for
the third year in a row have been observed, with the largest
growth in patent lings from Asian countries like China,
Japan and Korea [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. And there is also another increase of
2,8% in the number of led patents in 2013 compared to
2012 [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>In order to provide a system that supports the above
mentioned target audience1 in planning their research strategies
through (semi-) automated trend detection, one needs to
understand the information needs and working environments
of these user groups, and most important their
understanding of trends and requirements regarding the functionality
of a trend mining system. This paper reports the ndings
of a qualitative survey on this subject with both scientists,
who are working with patents, and information professionals
from the patent domain.</p>
      <p>The paper is organized as follows: In the next section related
work is presented, before the methodology of this study is
described in section 3. The subsequent sections present the
1For a more detailed description of the target audience see
section 3
results of the survey, followed by a discussion of the results
in section 5 and some concluding remarks.</p>
    </sec>
    <sec id="sec-3">
      <title>2. RELATED WORK</title>
      <p>
        There have been several papers that address the technical
perspective of trend mining in the patent domain. Most
of this work concentrates on identifying technology trends
retrospectively like [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Other work
considers related areas like the identi cation of patents with high
novelty [
        <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
        ] or are engaged with technology monitoring in
patents [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        Most work addresses the problem by the use of machine
learning techniques (e.g. [
        <xref ref-type="bibr" rid="ref11 ref17 ref2 ref9">2, 9, 11, 17</xref>
        ]), particularly by
employing clustering techniques (e.g. [
        <xref ref-type="bibr" rid="ref1 ref15">1, 15</xref>
        ]) and network
analysis (e.g. [
        <xref ref-type="bibr" rid="ref1 ref12 ref17 ref2 ref8">1, 2, 8, 12, 17</xref>
        ]). In most works the nal decision
about the existence of a trend is left to the users, to whom
the results are presented by di erent visualisation techniques
(e.g. see [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]).
      </p>
      <p>
        A wide range of features has been investigated in those
works, like terms selected based on their frequency, to
mention the most common one, (e.g. [
        <xref ref-type="bibr" rid="ref14 ref15">14, 15</xref>
        ]), adjective-noun
pairs for potential technology features and verb-noun pairs
for potential technology functions [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ], noun and verb phrases
[
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], or subjective-action-object-relations (e.g. [
        <xref ref-type="bibr" rid="ref2 ref4">2,4</xref>
        ]), but most
works don't present a sound evaluation of their approaches
or only evaluations on selected steps of the complete process,
due to the missing evaluation resources. Instead mostly case
studies are performed.
      </p>
      <p>To our knowledge no study on the understanding of trends
and the informational background of the potential users of
such a system has been conducted so far.</p>
    </sec>
    <sec id="sec-4">
      <title>3. METHOD</title>
      <p>We are interested in getting deeper insights in the users'
understanding of trends as well as their requirements towards
a trend mining system. Therefore and due to the lack of
prior studies in this area, we choose a qualitative approach
and conducted semi-structured interviews.</p>
      <p>In order to get a better idea of the working environment
and the speci c needs of information professionals in the
patent domain, two pre-interviews where conducted with
domain experts from a big information infrastructure institute
working with patents and o ering software products for
information professionals in the patent domain. Due to this
pre-interviews the area of interest was narrowed down to
the engineering sciences, as patent documents in
chemistryrelated domains add the additional challenge of handling
chemical notations, which is out of the scope of the project
in whose context this research is conducted.</p>
      <p>Seven interviews have been conducted subsequently. Three
interview partners are scientists (SCI1{3) and four
interview partners are information professionals (IP1{4), who
either have a background as professional patent searchers
(IP1, IP3), work in the IP management (IP2) or work in a
company o ering di erent patent services to clients (IP4).
Figure 1 shows the questions which were asked within the
interviews, where the questions were adapted to the
respective group of the target audience (scientists and information
professionals). The order of the questions was not
necessarily kept during the interviews, but was adapted to the
particular interview situation.</p>
      <p>The interviews were audio recorded and transcribed
afterwards2, before they were analyzed with regard to the
questions in gure 1.</p>
    </sec>
    <sec id="sec-5">
      <title>4. RESULTS</title>
      <p>In this section the insights from the interviews are presented.
First the characteristics of trends as viewed by the interview
partners are described, before questions and work tasks in
the area of trend analysis as well as strategies for trend
analysis are depicted. Section 4.4 takes a closer look at the parts
and sections of a patent, which are important for trend
mining. The section closes with an overview of the functions a
trend mining system should o er according to the interview
partners.</p>
    </sec>
    <sec id="sec-6">
      <title>4.1 Characteristics of Trends</title>
      <p>One main factor for recognizing a trend is the increasing
number of publications in that area (SCI1, SCI2, IP1, IP3).</p>
      <p>IP1 points out that there needs to be a critical mass of
patents, before you can name it a trend and suggests
numbers between 20 and 50 with a stronger tendency towards
50. IP2 also gives some numbers, which range from 10 to
15, likewise with a tendency towards the higher value. These
numbers can of course not be taken as strict rules, but they
show, that according to di erent disciplines magnitudes can
be quite di erent. One reason for this can be seen in the
size of the research area and another in the understanding
of a trend with regards to the content and the granularity
of interest.</p>
      <p>Other factors for recognizing a trend in the context of the
patent domain are the appearance of new IPC-classes or the
frequent co-occurrence of IPC-classes from di erent areas of
research assigned to the patents (IP1).</p>
      <p>When it comes to time spans of trend evolutions the
interview partners mostly agree, that it is a matter of several
years. IP2 is giving the smallest time span ranging from
several months up to one or two years, IP3 also gives a range
from about two years, whereas IP1, SCI1 and IP4 describe
longer time periods between ve years (IP1) and ten years
(IP4), with IP4 emphasising the fact that these numbers can
be quite di erent from discipline to discipline.</p>
      <p>According to the granularity of the abstraction level of the
content in the context of trend analysis the interview
partners are mainly interested in two levels, which are not
speci c to one group of interview partners: On the one hand
trends on the top level of an entire research area, and on
the other hand detailed subject-speci c or technical
developments within a eld of interest are mentioned. SCI1 explains
for example, that a scientist usually knows the speci c
developments within the own research area, whereas it would
be interesting to see trends of neighboring disciplines, which
might inspire the own direction of research. Contrariwise
2One interview partner did not allow to audio record the
interview, therefore the interview notes were used for further
analysis.</p>
      <p>Please give some details on your personal background and your working environment / on your research area .
Do you selectively conduct trend searches / analysis or trend observations?
Do you include patents in this search or analysis process?
What kind of questions do you want to answer by these trend searches / analysis?
How would you characterise such a trend or what makes a trend a trend in your working environment?
{ What kind of shapes with regard to the trend curve are of interest?
{ At which time points are those curves interesting?
{ What are the time periods we are talking about (months, years)?
{ Which time related elds should be used for measuring a trend?
{ What is the subject of a trend in terms of content (the granularity level of the content)?</p>
      <p>Could you give an example?
{ How would you measure such a trend?
{ Where can one see a trend at rst (what kind of publications)?
How do you realize, that a trend is developing?
What does the result of a trend analysis look like?
What strategy do you pursue, when you do a trend analysis and what steps can you identify in the process?
Which parts of a patent are most applicable or e ective in this context?
Which functions should a trend mining system o er?
SCI3 focuses on the more subject-speci c type of trends.</p>
      <p>As mentioned before the information professionals are also
interested in both types of trends. IP1 explains, that
customers who want to use a speci c technology (e.g. SMEs)
are more interested in IPC-class level trends, whereas
enterprises wanting to control a commercialization process or to
get full market coverage are interested in more ne grained
information, like on substance or technology level, when it
comes to trend analysis.</p>
    </sec>
    <sec id="sec-7">
      <title>4.2 Information Needs in Trend Analysis</title>
      <p>Trend searches or analysis are conducted with di erent aims
or objectives and are guided by di erent questions. One
question coming up in both groups of interview partners is
concerned with nding out if it is worthwhile to engage
oneself with a speci c research topic (SCI1, IP1, IP3), although
there are di erent reasons behind this question. SCI1 is
interested in knowing if there is a possibility of funding, that
is worth the e ort of preliminary work and writing an
application, as this process takes approximately 1.5 years. IP1
constitutes the importance of knowing if the area is already
covered by patents and IP3 expresses the situation, that the
existing patents mean, that competitors have been working
for more than 1.5 years in an area, once the patents are
available to the public, due to the 18 month delay in
publication.</p>
      <p>Another question in the context of trend analysis regards
the persons, research teams and companies already engaged
in the area of interest. On the one hand the interview
partners are interested in knowing how many of them are there
(SCI1), on the other hand they are speci cally interested
in observing the competitors (IP2) or nding out how big
the development team of a speci c competitor is, as this is
an indicator of how important a topic is to that competitor
(IP3).</p>
      <p>Other questions have a broader focus, e.g. ask about the
development of new technical elds (IP1) or the direction the
development in a technical eld is taking (IP1, IP4). There
are also questions which are dealing with possible markets
(IP1).</p>
    </sec>
    <sec id="sec-8">
      <title>4.3 Points of Interest in the Trend Evolution</title>
      <p>The above presented characteristics and information needs
do have an in uence on the points of interest within the
development of a trend. Most interview partners agree, that
the beginning of a trend is a point in time, when a trend
becomes interesting (SCI1, IP1{4). This is especially the
case, if the reason for the analysis is to get involved in a
speci c area of research.</p>
      <p>The information professionals also consider other points in
the evolution of a trend as interesting and stress the
dependence on the requests of the clients and customers (IP1, IP3,
IP4). Some customers are interested in licencing a speci c
technology, which means it needs to be functional already,
and therefore a later point in the evolution of the trend is
interesting (IP1). IP4 describes a similar scenario and assigns
descending trends to those customers. A descending trend
curve with regard to patent applications does not mean, that
a trend is ending, but that the technology has reached a
certain degree of maturity.</p>
    </sec>
    <sec id="sec-9">
      <title>4.4 Applicable Sections of a Patent for Trend</title>
    </sec>
    <sec id="sec-10">
      <title>Mining</title>
      <p>The question about applicable sections for trend mining on
the one hand aimed at clarifying which date related elds
should be used for trend mining and on the other hand which
content related sections of a patent are best suited for trend
mining.</p>
      <p>Date related elds for patents include application dates,
priority dates and publication dates. The application date
refers to the date of the application at the patent o ce,
whereas the publication date denotes the date, when the
patent was made available to the public, which can be up
to 18 month after the application was handed in. If there
are multiple applications to di erent patent o ces for an
invention, these patents form a patent family3. The earliest
application date of a patent family is denoted as the priority
date.</p>
      <p>
        Related work in trend mining on patents uses di erent date
related elds to explore temporal developments. Some works
choose the application date (e.g. [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]) while others prefer the
publication date of a patent (e.g. [
        <xref ref-type="bibr" rid="ref4 ref7">4,7</xref>
        ]). The interview
partners mostly agreed that for trend mining the priority date
would be the date related eld of choice. Although some
acknowledge, that one could use the application date (IP2,
IP3). According to IP1 the publication date could be
useful, if the impact of an invention on an industrial sector is
of interest.
      </p>
      <p>
        With respect to the content related sections, a wide variety
has been used in prior research: title and abstract have been
used as well as claims and descriptions and varying
combinations of these (e.g. see [
        <xref ref-type="bibr" rid="ref12 ref14 ref17 ref2 ref5">2, 5, 12, 14, 17</xref>
        ]). The same variety is
also found in the interviews. Table 1 lists the content related
sections suggested or excluded by the individual interview
partners.
      </p>
      <p>Especially when it comes to titles and abstracts the
opinions diverge. IP1 explains, that it depends on the database
whether these two elds could be used for determining the
content of a patent: Some providers of patent information
offer added values like manually rewritten titles and abstracts
according to the contents of a patent and therefore make
these a good data resource, while titles and abstracts taken
directly from the patent application often form a bad base
for analysis (IP1) as the applicants try to conceal the
content and claim of a patent, in order to keep it as broad as
possible.
3For further details on patent families see for example http:
//www.intellogist.com/wiki/Patent_Families</p>
      <p>rst main claim, main
claims (SCI1)
claims (SCI3)
description
SCI3)</p>
      <p>(SCI2,
gures (SCI3)
claims (IP4)
perh. claims (IP3)</p>
      <p>rst page of the description
(IP3)
the replication of contents in
the description dilute the
results (IP1)</p>
      <p>gures (IP2)
perh. gures (not for
informatics or
telecommunications)
edited / enhanced titles (IP1)
titles (IP3)
edited / enhanced abstracts
(IP1)
abstract (IP2, IP3)
abstracts are too general
(IP4)
introduction, especially the
task description (IP3)</p>
    </sec>
    <sec id="sec-11">
      <title>4.5 Trend Analysis Strategy</title>
      <p>Besides the information needs and their understanding of a
trend the interview partners were also asked for their
strategies with regard to trend searches and analysis.</p>
      <p>IP1 gives descriptions of strategies for both of the above
mentioned trend types. When the interest is primarily on
the rst type of trends e.g. within an IPC-class, he rst
creates a basic set of documents and then aggregates the
patents with regard to their respective patent families in
order to avoid duplicate counting of the same invention. If
necessary the document set is further aggregated according
to national patent families and then the number of patents
per year based on the priority date are calculated and
visualized. The last step would be to select technology areas
with growth above average and if necessesary conduct
further analysis.</p>
      <p>For the second trend type IP1 proposes an iterative
approach, involving the client at every stage of the process.
Especially at the beginning, according to IP1 clients are not
always able to explain their objectives or questions
explicitly. Another point is, that concept names used within one
company might be di erent from those commonly used in
patents, or there might as well be some variety in the
concept names found in the respective patents. Therefore as a
rst step a patent landscape of the domain of interest needs
to be generated and then explored together with the client.
This serves the goal of getting a common understanding of
the task at hand and identifying aspects of a topic which
are of special interest to the client. These identi ed areas
are then further analyzed with text mining techniques like</p>
      <p>IP3 gives a description of how to get the basic document set
for the analysis. He starts o with known competitor names
and their publications and then looks at the IPC classes and
might take those into consideration as well.</p>
    </sec>
    <sec id="sec-12">
      <title>4.6 Functions of a Trend Mining System</title>
      <p>At the end of the interview the scientists and information
professionals were asked what kind of functions a trend
mining system should possess. These range from possibilities
to drill down within a research area to more speci c areas
and explore trends at every stage, to having an alert
function informing about changes in a prede ned area of interest
(SCI1).</p>
      <p>IP1 describes the ideal trend mining system as a system
possessing two modes, one standard mode and one advanced
mode for experts. Both modes should be transparent to the
user and make interim results accessible in order to make the
process comprehensible. The advanced mode should
additionally give the possibility of taking actions at various steps
during the process, like incorporating additional knowledge
about the domain in question or de ning the number of
clusters that should be build during a clustering step.
Another important aspect are interactive visualisations of
the results, enabling the user for example to zoom in for
more details (IP3). IP1 also remarks that visualisations that
help to understand the contents of a set of documents is
a desirable feature and make it possible to explore results
together with costumers.</p>
    </sec>
    <sec id="sec-13">
      <title>5. DISCUSSION</title>
      <p>As this study has the character of an exploratory study and
only a small sample is involved, the ndings of this study can
only give rst insights into the domain and a starting point
for further research, but the variety of information needs and
understandings of trends within just the eld of engineering
sciences emphasises the necessity of incorporating the
target audience in the development process of a trend mining
system.</p>
      <p>The presented results show that there are quite a few di
erences in the understanding of trends or the characteristics
that make a trend interesting to the target audience,
although the interview partners mostly had a background in
engineering.</p>
      <p>Mainly two types of trends, that are interesting to the target
audience, could be identi ed: Trends at the top level of an
entire research area or domain and subject-speci c or
technical developments within a speci c area of interest. The
results also show, that the time spans encompassing a trend
can be quite di erent according to the content granularity
of interest and the domain of interest.</p>
      <p>Additionally the results of the interviews show, that not only
emerging trends are of interest to the target audience, but
also trends which have reached their height or are even on
a decreasing path, as this denotes, that a technology has
reached a stage, where it can be used, and licenced by other
organisations to incorporate them in their own products.
The interest on trends at this stage are mainly ascribed to
SMEs.</p>
      <p>The study also shows that research is needed with regard
to the question of which content related sections of a patent
are best applicable for trend mining, due to the fact that
almost every content related section has been named by at
least one interview partner.</p>
      <p>The ndings show as well, that at least for some of the
patents searchers it is important to integrate their customers
and clients in the trend mining process. Therefore a system
with such a target audience should also incorporate
visualisation techniques, that allow for exploring analysis results
together with clients and make it easy for a non-patent
specialist to understand the results shown by the trend mining
system.</p>
    </sec>
    <sec id="sec-14">
      <title>6. CONCLUSIONS</title>
      <p>This paper gives rst insights into the user perspective of
trend analysis in the patent domain. Besides showing
different perspectives and understandings of trends as well as
pointing out characteristics making a trend interesting to
the target audience within the area of engineering sciences,
the study gives rst insights into the underlying tasks and
information needs of the target audience and some
requirements regarding the functionality of a trend mining system
in the patent domain.</p>
      <p>The study also shows the necessity for further research when
it comes to the question of which content related sections of
a patents are applicable for trend mining, as there is neither
a clear picture on this aspect from the interviews, nor is
there in related research.</p>
    </sec>
    <sec id="sec-15">
      <title>7. ACKNOWLEDGMENTS</title>
      <p>This work was conducted as part of the project
\Trendmining fur die Wissenschaft"4 (T4P), which is a joint project
of FIZ Karlsruhe { Leibniz Institute for Information
Infrastructure and the Institute for Information Science and
Natural Language Processing at the University of Hildesheim
and is funded by the Leibniz Association in the context of
the Leibniz Competition.</p>
    </sec>
  </body>
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