<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Study of Basis on AI-based Information Systems: The Case of Shogi AI System “Ponanza”</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Yuichi YODA</string-name>
          <email>yyoda@stanford.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kosuke MIZUKOSHI</string-name>
          <email>mizukoshi-kosuke@tmu.ac.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Seiichiro HONJO</string-name>
          <email>seihonjo@shizuoka.ac.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Management of Business Development, Shizuoka University 3-5-1 Jouhoku, Naka-ku Hamamatsu city</institution>
          ,
          <addr-line>Shizuoka</addr-line>
          ,
          <country country="JP">Japan</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Faculty of Economics and Business Administration, Tokyo Metropolitan University 1-1 Minamiosawa</institution>
          ,
          <addr-line>Hachioji city, Tokyo</addr-line>
          ,
          <country country="JP">Japan</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>US-Asia Technology Management Center, Stanford University 521</institution>
          <addr-line>Memorial Way, Stanford, California</addr-line>
          ,
          <country country="US">U.S.A</country>
        </aff>
      </contrib-group>
      <abstract>
        <p />
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>The objective of this study is to deepen our understanding
about the exploration of Artificial Intelligence (AI) in
corporate marketing and interpret how people and society
respond in their attempt to comprehend the development and
actions of AI.</p>
      <p>In this study, we discuss the case of Ponanza, an AI
based system for Japanese Chess “Shogi”. We conclude that
Ponanza became a mystery even for its developers in their
process of building this system into one capable of defeating
professional Shogi players and is now open to interpretation
for its developers and professionals.</p>
      <p>In particular, when we treat AI as an extension of humans,
it will be important to consider how AI and humans create
knowledge and how humans can learn from AI. In the future,
interaction with AI can be expected to improve human’s
ability to investigate “causes” and develop “reasons”.</p>
    </sec>
    <sec id="sec-2">
      <title>Introduction</title>
      <p>
        With the spread of AI in recent years, there has been a
change in the way people understand its occupational
practice. Many of the occupations currently performed by
humans are expected to be replaced by AI in the near future
        <xref ref-type="bibr" rid="ref1 ref2">(Frey and Osborne, 2017)</xref>
        . Not only that, but the way
occupational practices are undertaken is also undergoing
change. Until now, marketing research placed importance
on building hypotheses and providing reasons about users’
consumption behavior. In contrast, Amazon’s
recommendation system and Google’s search engine, which use
machine learning, respond to user needs based on data
accumulated from the customers’ buying patterns. These
systems do not rely on causal relationships and work as long
as there is a correlation between data
        <xref ref-type="bibr" rid="ref2">(Mayer-Schö nberger
and Cukier, 2013)</xref>
        . In marketing practice, there are three
merits of focusing on the “result” of selections made by
users in the real environment and responding to user needs
through trial and error – (1) it conforms with the way of
thinking of companies that focus on results, (2) it leverages
the low cost of needs exploration in Internet business, and
(3) it enables the company to incorporate complicated
environmental factors which move dynamically when a
proposal is made to the user
        <xref ref-type="bibr" rid="ref6">(Yoda, Mizukoshi and Honjo,
2016)</xref>
        . This method is expected to grow in future.
      </p>
      <p>On the other hand, such result-focused practice is
dissociated with existing human activity from the viewpoint of
systematic understanding because it does not specify cause
and effect. From the perspective of research, this leads to
difficulties in constructing theories on user needs or human
behavior in general. From the practical perspective, this
raises difficulties because the “results” cannot be
reproduced as they are limited to certain conditions and
horizontal expansion of business is not easy. This study focuses on
AI that surpasses human achievements to analyze the
workings of human understanding for a phenomenon and
the relationship between AI and humans.</p>
    </sec>
    <sec id="sec-3">
      <title>Research Method</title>
      <p>We study the case of a Shogi program that uses AI (Shogi
AI). Shogi is the best subject for studying the relationship
between AI and humans because of the following three
reasons - (1) it is a game with fixed rules, played in a static
environment and can therefore be studied as a case
separated from the complicated and dynamic environment of
society, (2) professional Shogi players are considered one of
the representative examples of the human intellect and (3)
superiority dispute between AI and humans is already
settled with Shogi AI far surpassing Shogi players.</p>
      <p>In this study, the “case study” method as a qualitative
research is adopted. Case study is an effective method for
exploratory research allowing us to ask “how” and ”why”
of high-context phenomena beyond the control of the
researcher (Yin, 1994)[4]. It is also suitable for exploratory
research of unique cases. The case study approach can be
conducted adhering three principles of data collection to
handle qualitative data as a scientific research approach
proposed, vis-à-vis data correctness such as (1) use of
multiple sources, (2) use of face-to-face interview, (3)
maintenance of a chain of evidence by Yin (1994).</p>
      <p>This case study is based on an interview with Issei
Yamamoto1, the developer of major Shogi AI Ponanza, his
public lectures, books and other related disclosed materials.
Additionally, we requested Seiya Tomita (3-dan player in
the Encouragement Meeting) of the Japan Shogi
Association to accompany us during Issei Yamamoto’s interview
and lectures. Before and after the events, we benefitted
from his expert knowledge on the thinking process
involved in Shogi. We also used interview videos and books
by Shogi players Yoshiharu Habu and Amahiko Satoh as
reference materials for the analysis.</p>
      <sec id="sec-3-1">
        <title>Case Study of Shogi AI Ponanza2</title>
        <p>(1) Overview of Ponanza
Ponanza is a Shogi program that Issei Yamamoto started
developing while he was studying in the University of
Tokyo. As Shogi AI, it defeated a professional Shogi player
for the first time on March 30, 2013. On May 20, 2017, it
became the first Shogi AI to beat an active Shogi “Meijin”
which is the most prestigious title of Shogi in Japan.</p>
        <p>
          Yamamoto explained that as in the case of human
intellectual activities, Shogi AI too requires two functions
– exploration and evaluation. Exploration, here, refers to
the ability to predict and correctly emulate (make a guess
without adding one’s subjective views or judgement) the
future3. To anticipate the future, the computer explores a
2007
2013
2015
large number of situations on the board, calculates all
possible moves from those situations and predicts how the
game is likely to unfold. In the case of humans, this is
called “reading” which means exploring
          <xref ref-type="bibr" rid="ref5">(Yamamoto, 2017,
Ch. 1, Sec. 3, Para.8)</xref>
          . However, because it is difficult to
completely explore all of the large number of situations
due to resource constraints, computers determine the next
move while marking out some highlights. This process of
marking highlights is referred to as evaluation. In other
words, the area of exploration is gradually reduced as
needed to effectively use the limited resources (Ibid., Ch. 1,
Sec. 3, Para.10-12). Yamamoto said that humans program
the “exploration” part, which was a main function, and
specified how the exploration was to be conducted, while
the computer learns to “evaluate” by itself through the
introduction of machine learning (Ibid., Ch. 1, Sec. 14,
Para.1).
        </p>
        <p>It can be said that the difficulty in evaluating Shogi lies
in the fact that no optimum method of calculation has been
found for computers yet because of the game’s complexity
and depth4. Ponanza needed a function to express the
adjustments between the more than one hundred million
parameters as “evaluation parameters” in order to represent
the complexity of Shogi, based on three-piece relationships,
including the king5, and the turns6. Yamamoto said that the
initial version of Ponanza improved Shogi AI to a level
where it could play moves similar to about 45% of the
professional Shogi players7. This was done by enabling the
computer to adjust the values after using machine learning
to acquire the game records of over 50,000 Shogi players
as training data. Machine learning based parameter
adjustments by computers are faster and more accurate than
manual parameter adjustments by humans. Therefore,
Yamamoto decided to thoroughly train (adjust parameters)
the computer for the parameter function and devoted
himself to describing through a program how the computer
should be trained to evaluate.</p>
        <p>Then, on March 30, 2013, the computer defeated an
professional Shogi player for the first time. The match was
played against Shinichi Satoh, 4-dan, in the 2nd Den-o Sen
(Electronic King Championship). The Ponanza at that time
was able to explore 40 million situations in one second.</p>
        <p>Furthermore, Yamamoto introduced reinforcement
learning, which is unsupervised learning, in 2014, after
working on supervised learning where Ponanza learned
from game records of Shogi players8. In this method, the
computer makes speculative searches even if the
environment is unfamiliar and learns through feedbacks received
about the results. Repeated feedbacks strengthen the
computer’s evaluation function. To be specific, it makes six to
eight moves based on a probable situation, analyzes
whether they led to victories and finetunes evaluation
parameters. Yamamoto says that he accumulates about eight
billion such situations and has eventually analyzed nearly
one trillion situations. This process results in determining
new Ponanza-style tactics, which refers to sequences that
do not exist in games played between humans.</p>
        <p>(2) Developer’s Perspective
As Ponanza’s performance improves, it is becoming more
and more difficult to be explained. Yamamoto compared
its mystery to “Black magic9.” This term is accepted as a
slang in the machine learning world too and refers to an
umbrella term for any technique whose origin and reason
for effectiveness is unknown.</p>
        <p>When making improvements in Ponanza, every time
Yamamoto thought of a new improvement, he would
initiate about 3,000 automatic matches between the Ponanza on
which the improvement was applied and an older version.
The improvement would be implemented if the new
Ponanza won 52% or more matches. However, Yamamoto
says that he had no clue about the workings of the
improvements that proved effective. In concrete terms, he
says that he does not understand the real reason why the
values fed in the program work or why a certain
combination of values is effective. Yamamoto adds that he cannot
analyze Ponanza’s effectiveness because he does not know
why it wins or loses a match, as the program’s Shogi
strength surpasses that of its developer Yamamoto.</p>
        <p>As a concrete example of the black magic, Yamamoto
gives the example of idle parallelization. In this method,
multiple cores of the CPU separately carry out the same
processing and the effective methods that each core
accidently discovers are shared with the entire system.
Interestingly, even experts find it difficult to explain why
randomly shared methods work well. They say that their best
possible explanation is that “an experiment turned out well.”</p>
        <p>To sum up, Yamamoto says that he is unable to provide
an accurate explanation of why Ponanza is strong and adds
that he can only make it stronger through experimentation
and experience.</p>
        <p>(3) Shogi Players’ Perspective
In the 2nd Den-o Sen, held in April and May 2017,
Ponanza became the first Shogi AI to defeat an active Meijin.</p>
        <p>Yamamoto mentioned in the 53rd turn of the first game
as an example of symbolic moves by Shogi AI. In this,
Shogi AI made an exceptional move to build defense by
giving up a piece to the Meijin who had no attacking
pieces. This was against Shogi theory, in which players are
expected to move across the board without giving up
pieces to the attacking player.</p>
        <p>
          The opponent, Satoh Meijin, too felt surprised that such
a move was possible when he saw this happen. He said he
was unable to understand the meaning of the move because
he held preconceived notions such as sacrificing a pawn
when the opponent has two pieces that are effective. He
said that he was unable to anticipate the move.
          <xref ref-type="bibr" rid="ref2">(Satoh
Meijin, NHK, July 31, 2017)</xref>
          . Moreover, Yoshiharu Habu
explained “humans found it difficult to imagine a situation
where a player would use a piece that is neither attacking
nor defending, and even give up a pawn to the opponent
who does not have one”.
          <xref ref-type="bibr" rid="ref2">(Habu, NHK 2017)</xref>
          .
        </p>
        <p>
          Satoh Meijin says that this showed that there could be
best moves in Shogi that humans do not see any reason for
(that humans find difficult to understand).
          <xref ref-type="bibr" rid="ref2">(Satoh Meijin,
NHK 2017)</xref>
          .
        </p>
        <p>Shogi AI has already surpassed Shogi players. The
dispute of superiority between humans and AI has been
settled as far as Shogi is concerned. However, humans,
including Shogi players, have not abandoned Shogi. Shogi
players are beginning to find ways to learn from Shogi AI
as part of their research on the game. Tomita, who
frequently participates in study groups with Shogi players,
says that the Shogi players he knows are placing
importance on learning positioning judgement from Shogi AI.
In concrete terms, this means that Shogi players can
improve their game by comparing their evaluation results
with those of Shogi AI and refining their positioning
judgement for each situation on the board.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Discussion</title>
      <p>It can be said that human understanding for the logic
behind Shogi AI’s strength has transformed through the
following three stages. In the first stage, players thought that
the logic behind Shogi’s strength lies within professional
Shogi players and they sought to know how Shogi AI
replicates the moves made by professional Shogi players. The
focal point was whether the sources of strength that they
expressed in their own language could be translated into
machine language. In the second stage, the logic of
strength moved from professional Shogi players to Shogi
AI. The developer of Bonanza discovered a method of
considering the positioning of three pieces, rather than two, to
determine the best move. At that time, it could be said that
the translation was realized. The developer worked actively
on the logic of strength which had now moved to Shogi AI
and attempted to adjust parameters. In the third stage, the
logic of strength was internalized in Shogi AI and came to
be considered as something humans are unable to see.
Shogi AI became capable of adjusting the logic of strength
by itself through reinforcement learning. It was no longer
clear why Shogi AI performed the way it did, and the
developer’s adjustments came to be considered as black
magic.</p>
      <p>The internalization of the logic of strength in Shogi AI
meant that Shogi AI is superior to human Shogi players. At
the same time, this also increased initiatives among
professional Shogi players to learn from Shogi AI. To learn from
Shogi AI and improve their own game, professional Shogi
players must translate the logic of Shogi AI’s strength back
into their own language. It will be important once again for
professional Shogi players to be able to understand and
explain why their Shogi AI opponent makes certain moves.</p>
      <p>Shogi players are tasked with learning and explaining
why something worked, although they do not understand it.
This gives rise to the problem of how humans deal with a
phenomenon and gain an understanding of it as far as the
relationship between humans and AI is concerned. By
generalizing the example of Shogi AI, we find that humans are
capable of taking two kinds of approaches. One is to treat
AI as a physical phenomenon and the other is to deal with
it as an extension to humans.</p>
      <p>The first approach of treating AI as a physical
phenomenon would mean that we just need to confirm that a certain
result is produced under certain conditions, even though
we do not understand the logic behind it. At this stage, it
will be possible to apply AI using the phenomenon.
Moreover, the current relationship between AI and humans can
be interpreted as similar to the relationship between the
steam engine and humans, before thermodynamics was
discovered. Humans learned from the steam engines,
which was produced from experience; investigated the
causal relationship in its working principle and built the
thermodynamics theory, thereby gaining a systematic
understanding. This requires an investigation of the “cause”
of a phenomena without depending on language. It can be
said that from the third stage, where the logic of strength is
internalized in Shogi AI, humans try to deepen their
understanding in order to return to the second stage where they
can intervene in its contents. However, the difficulty of
determining the cause has become extremely increased and
it is a big challenge for humans.</p>
      <p>
        On the other hand, in the approach where AI is
considered an extension of humans, humans advance their
understanding of the results presented by AI while building a
model and seek “reasons” as a foundation for
understanding. This corresponds with acknowledging as given the
third stage, in which the logic of strength is beyond human
comprehension. As is evident from the comments of Shogi
players, such as humans find it difficult to imagine a
situation where a player would use a piece that is neither
attacking, nor defending, and even give up a pawn to the
opponent who does not have one
        <xref ref-type="bibr" rid="ref1 ref2">(Habu and NHK, 2017)</xref>
        , they
interpret AI as a person and try to learn from it. In such a
case, humans and society, not AI, ask the foundation as to
“why” AI is able to produce certain results. That is why,
contextual and language-based “reasons” should be
expected by humans and society. The challenge here is to
produce a logic to justify the foundation just like logical
reasoning rather than discovering a working principle or
“cause.”
      </p>
      <p>
        Various experiments in social psychology have shown
that humans rationalize their actions using “reason” that
are different from the “cause.” For example, consumers
were asked to explain the “reason” for selecting the most
high-quality nylon stockings from among identical
products. Although a larger number of the consumers selected
stockings kept on the right side, they mentioned the
difference in the quality of the stockings while explaining their
reason and not the positioning
        <xref ref-type="bibr" rid="ref3">(Nisbett and Wilson, 1977)</xref>
        .
Although AI does not automatically justify its actions by
itself, its actions can be seen as an extension of human
behavior if we consider it as a subject for seeking “reason”
after the action is performed.
      </p>
      <p>
        Moreover, when we consider AI as an extension of
humans, we can also anticipate the approach the other side
takes when thinking. The Organizational Knowledge
Creation Theory holds that knowledge is created, shared in the
organization and accumulated through the repeated process
of four phases of the SECI model: Socialization, where
people create or integrate tacit knowledge by sharing
experience; Externalization, where people express tacit
knowledge in clear concepts to convert it into explicit
knowledge; Combination, where people combine concepts
to build a knowledge structure; and Internalization, where
people embody explicit knowledge into tacit knowledge
        <xref ref-type="bibr" rid="ref4">(Nonaka and Takeuchi, 1995)</xref>
        . During externalization in
the SECI model, tacit knowledge is converted into explicit
knowledge through dialogue between individuals. The
concept of dialogue between two humans may be extended
to imagine an interaction between AI and humans where
the latter learns from the former. As an extension to that, it
might be effective to try to provide an explanation to this
highly persuasive phenomenon from the acts of personified
AI, using human abilities for intuition and logic. This
could lead to new research questions, such as what the
meaning of a dialogue with AI is or whether there is a
difference between people who can learn from AI and those
who cannot.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Conclusion</title>
      <p>In this study, we analyzed the case of Shogi AI to explore
how humans comprehend the performance of AI that
produces results that surpass humans. There are various
important social issues about AI that need to be handled.
These include who is responsible for the moral obligations
with respect to the results produced independently by AI
and how to handle social biases that are already a part of
the training data. However, these issues are based on the
premise of using AI as a tool governed by humans. This
study sheds light on the approaches of treating AI as a
physical phenomenon and an extension of humans, and
shows that these approaches give rise to problems of a
different kind. In particular, when we treat AI as an extension
of humans, it will be important to consider how AI and
humans create knowledge and how humans can learn from
AI. AI is producing better results than humans in various
fields. In the future, interaction with AI can be expected to
improve human’s ability to investigate “causes” and
develop “reasons.”</p>
      <sec id="sec-5-1">
        <title>Acknowledgements</title>
        <p>In this study, we learned immensely from Issei Yamamoto,
the developer of Shogi AI Ponanza, about his experiences
and knowledge through the interview with him. We also
received a wealth of information about the perspectives of
Shogi players from Seiya Tomita, a member of the Japan
Shogi Association. We are grateful to both for their
invaluable support. Funding from the Telecommunication
Advanced Foundation, Ritsumeikan University, Japan
Marketing Academy, and JSPS KAKENHI Grant Number
JP18K12878 is gratefully acknowledged.</p>
      </sec>
      <sec id="sec-5-2">
        <title>Endnotes</title>
        <p>
          1 Issei Yamamoto, Developer of Shogi Program “Ponanza”,
Specialty Appointed Associate Professor at Aichi Gakuin University,
Research Associate at Research Center for Advanced Science and
Technology of Tokyo University, Lead Engineer at HEROZ, He
started developing Shogi program Ponanza while he was a
student in the Faculty of Engineering, University of Tokyo. The
program became the first Shogi AI to defeat an active
professional Shogi player in a public match in the Shogi Den-o Sen event
held in 2013. In the 2017 Shogi Den-o Sen, it defeated an active
professional “Meijin” for the first time.
2 This case study is based on Issei Yamamoto’s lecture (held at
Tokyo Metropolitan University Akihabara Campus) on September
22, 2017, a private interview with him on the same day and his
book.
3 Yamamoto, 2017, Ch. 1, Sec. 3, Para. 5
4 For instance, making computer-based calculations about the
quality of a situation is considered more difficult and tough to
handle in Shogi than in Chess. In chess, the presence or absence
of pieces on the board is directly related to how good or bad the
phase is and can be represented more easily in the form of logic.
However, in Shogi, the positioning of the pieces determines the
quality of the situation and is therefore difficult to represent in the
form of logic.
          <xref ref-type="bibr" rid="ref5">(Yamamoto, 2017, Ch.1, Sec.10)</xref>
          .
5 Yamamoto, 2017, Ch. 5, Sec. 1
6 Retrieved February 20th,2018, “Ponanza Document (2010)
http://www.computershogi.org/wcsc20/appeal/Ponanza/Ponanza.pdf”
7 Yamamoto, 2017, Ch. 1, Sec. 12, Para. 7
8 Yamamoto, 2017, Ch. 1, Sec. 13
9 This refers to the magic used by witches to make mysterious
medicines in the world of fairy tales and fantasy.
          <xref ref-type="bibr" rid="ref5">(Yamamoto,
2017, Ch. 2, Sec. 1, Para. 2)</xref>
        </p>
      </sec>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          <string-name>
            <surname>Frey</surname>
            ,
            <given-names>C. B.</given-names>
          </string-name>
          , and
          <string-name>
            <surname>Osborne</surname>
            ,
            <given-names>M. A.</given-names>
          </string-name>
          <year>2017</year>
          .
          <article-title>The future of employment: how susceptible are jobs to computerisation?</article-title>
          .
          <source>Technological Forecasting and Social Change</source>
          ,
          <volume>114</volume>
          :
          <fpage>254</fpage>
          -
          <lpage>280</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          <string-name>
            <surname>Habu Y.</surname>
          </string-name>
          and NHK Special Coverage Groupe
          <year>2017</year>
          .
          <article-title>The core of artificial intelligence:</article-title>
          <string-name>
            <surname>NHK Shuppan Ichinose</surname>
            <given-names>M.</given-names>
          </string-name>
          <year>2006</year>
          .
          <article-title>Labyrinth of causes and reasons: Philosophy of 'Why': Keisoshobou Mayer-Schö nberger, V., and</article-title>
          K. Cukier
          <year>2013</year>
          .
          <article-title>Big data: A revolution that will transform how we live, work, and think:Houghton Mifflin Harcourt</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          <string-name>
            <surname>Nisbett</surname>
            ,
            <given-names>R. E.</given-names>
          </string-name>
          and
          <string-name>
            <surname>Timothy</surname>
            <given-names>D. W.</given-names>
          </string-name>
          <year>1977</year>
          .
          <article-title>Telling more than we can know: Verbal reports on mental processes</article-title>
          ,
          <source>Psychological Review</source>
          <volume>84</volume>
          (
          <issue>3</issue>
          ):
          <fpage>231</fpage>
          -
          <lpage>259</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          <string-name>
            <surname>Nonaka</surname>
            ,
            <given-names>I. and H. Takeuchi 1995. The</given-names>
          </string-name>
          <string-name>
            <surname>Knowledge-Creating Company</surname>
          </string-name>
          :New York: Oxford University Press.
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          <string-name>
            <surname>Yamamoto</surname>
            <given-names>I.</given-names>
          </string-name>
          <year>2017</year>
          .
          <article-title>How did AI exceed Shogi Meijin?: The essence of Machine learning, Deep leaning and Reinforcement learning by the developer of AI Ponanza which is the strongest Shogi AI:Diamond [Kindle version] Retrieved from Amazon</article-title>
          .com Yin,
          <string-name>
            <surname>R. K.</surname>
          </string-name>
          <year>1994</year>
          . Case Study Research,
          <string-name>
            <given-names>Y Sage</given-names>
            <surname>Publications</surname>
          </string-name>
          , Inc.
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          <string-name>
            <given-names>Yoda Y.</given-names>
            ,
            <surname>Mizukoshi</surname>
          </string-name>
          <string-name>
            <given-names>K.</given-names>
            and
            <surname>Honjo</surname>
          </string-name>
          <string-name>
            <surname>S.</surname>
          </string-name>
          <year>2016</year>
          .
          <article-title>A Consideration of the "Result" and "Reason" in the Exploration Process of the User Needs utilizing AI : From Cases of Amazon. com and Google :The Ritsumeikan business review</article-title>
          ,
          <volume>55</volume>
          (
          <issue>3</issue>
          ):
          <fpage>22</fpage>
          -
          <lpage>47</lpage>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>