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        <article-title>A Prototype Method for Future Event Prediction Based on Future Reference Sentence Extraction</article-title>
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      <fpage>42</fpage>
      <lpage>49</lpage>
      <abstract>
        <p>This paper presents our study on future prediction support method based on state-of-the-art natural language processing and pattern extraction techniques. We propose two practical applications of the method. The first is supporting future prediction in human users. The second is automatic future prediction based on provided data. We conduct experiments on the developed prototype method and evaluate its effectiveness. In the development of the method we assumed that sentences from official sources such as newspapers that refer to future events could be useful for future prediction. By using sophisticated patterns combining morphemes and semantic roles, we successfully extracted future reference sentences and effectively used them in future prediction performed both by human users as well as by the fully automatic prototype method. In the experiments we tested the method on a number of future prediction questions from official Future Prediction Competence Test, performed yearly in Japan. Both, the results of the support application as well as the automatic method were higher then the results of original test participants. Moreover, the prototype fully automatic method greatly outperformed all human users. This suggests that the method can be expected to not only reduce the response time and the amount of information needed for prediction in humans, but also perform the prediction automatically on a level comparable and exceeding an average human.</p>
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      <title>-</title>
      <p>One of the main tasks in the field of Artificial Intelligence
(AI) is providing means for understanding of the reality
around us and predicting possible outcomes of certain
decisions. The understanding is often restricted to analysis of
specific general meaning of, e.g., a particular instance of
language behavior (sentences, documents, etc.). For example, in
subfields of AI such as Natural Language Processing (NLP),
or Sentiment Analysis, speaker attitudes and emotions
expressed in a sentence are in the focus of analysis. A different
kind of task from the field of NLP, which we focus on in this
research, is predicting trends of future events on the basis of
provided limited information.</p>
      <p>In everyday life people often apply their knowledge and
experience about past events as well as their own general
knowledge to predict future events. In such everyday
predictions people often use widely available resources
(newspapers, Internet). Especially people who bare significant
social responsibility, such as politicians, managers, strategists,
planing specialists, or policy developers in large companies
are in need of tools that would support them in their
predictions and decision making, since the company’s results and
profits depend on how accurate their competence in future
trend prediction is.</p>
      <p>The goal of this study is to provide a tool, that would help
in such predictions. In particular, we aim at creating a
system that would perform such predictions automatically. To
achieve this we focus on sentences referring to the future as
potentially useful in predicting future unfolding of events.</p>
      <p>When humans consider future events, they usually process
the information from various domains to join it in one
reasoning. For example, when a company finds out that a decision
they need to take depends on two events/factors, ‘X’ and ‘Y’
(although in real life the number of factors is much larger),
they can prepare four strategic decisions A, B, C or D for
their company management, depending on the predictions on
what would happen in the future when they select:
1. Strategic decision ‘A’ when both events ‘X’ and ‘Y’ take place.
2. Strategic decision ‘B’ when the event ‘X’ takes place but the
event ‘Y’ does not.
3. Strategic decision ‘C’ when the event ‘Y’ takes place but the
event ‘X’ does not.
4. Strategic decision ‘D’ when both events ‘X’ and ‘Y’ do not take
place.</p>
      <p>When people select their actions from a range of possible
options, usually they consider and combine a wide spectrum
of information, including one’s and also other people’s
experiences and expertise regarding the events. Obtaining such
information for future predictions is a challenging task
requiring much time and labor with a lot of information to process
and deep foresight ability for making the decision.</p>
      <p>When predicting future events such as X and Y, for
example, “Will consumers do shopping with augmented reality
(AR) in two years time?” we can think of the following
possibilities: (1) More than half of consumers will shop with
AR; (2) Several percent of consumers will shop with AR; (3)
The way of shopping will not change comparing to current
situation. This way we can reduce the problem of future
prediction to predicting which of the limited number of potential
answers (two or more) has higher probability of occurring.
The predicting thus can be formulated as selecting the correct
answer, even if the answer is not yet specified at the time of
prediction.</p>
      <p>Previous studies have shown that data mining using
simple statistics can support such predictions regarding future
outcomes of events. However, to achieve that, one needs to
process numerous numeric data, which requires professional
skills, and the expertise to explain the numbers in a
comprehensible manner.</p>
      <p>There have also been studies on predicting future outcomes
of events with the use of NLP techniques. Some of them
have proposed applying causality information and past events
[Radinsky et al. 2012], which assume that when the event
A happens, the event B will usually follow. However, such
methods usually are limited to general events from the range
of widely perceived common sense (e.g., “what will
happened when an apple falls on ones head”). Others applied
methods based on keyword extraction with their occurrence
frequencies in a timeline using past events, temporal
expressions and event-related keywords [Kanazawa et al. 2011].</p>
      <p>As for a different research, [Nakajima et al. 2016] have
proposed a method for automatic extraction of future
reference sentences using combined morphological and semantic
(morphosemantic) information and suggested that future
reference sentences could be applied in supporting predictions
about future events, since they usually contain various related
background information, which is also used as the source of
knowledge for prediction.</p>
      <p>In this research we propose a prototype method which
applies such future reference sentences in the process of future
prediction. In the experiments we compare the performance
of laypeople and the proposed automated approach and
discuss its effectiveness.</p>
      <p>The outline of this paper is as follows. In Section 2 we
describe previous research related to the prediction of future
events. Section 3 describes the proposed method applying
automatic extraction of references to future events and the
experiments evaluating the method. Section 4 describes the
experiment to verify the effectiveness of future reference
sentences applied to real-world future prediction events. Section
5 describes the prototype method for automated prediction of
event unfolding. Finally, section 6 contains conclusions and
our plans for improvement of the prototype method and
possible applications of the proposed method in future tasks.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Previous Research</title>
      <p>There has been a number of studies in linguistically expressed
future reference detection.</p>
      <p>For example, [Baeza-Yates 2005] investigated half a
million of sentences containing future events extracted from one
day of Google News (http://news.google.com/), and found
out that scheduled events occur with high probability and with
correlation between the occurrence of an event and its time
proximity. Therefore the information about upcoming events
is of a high importance for predicting future outcomes.</p>
      <p>[Jatowt et al. 2009] also focused on news articles, and used
a rate of incidence of reconstructed news articles over time
to forecast recurring events, which they used for supporting
human user analysis of occurring future phenomena.</p>
      <p>[Kanhabua et al. 2011] in their investigation of
newspaper articles, found out that one-third of all sentences contains
some reference to the future.</p>
      <p>[Kanazawa et al. 2010] extracted implications for future
information from the Web using explicit information, such as
time expressions.</p>
      <p>When it comes to predicting the probability of an event to
occur in the future, [Jatowt and Au Yeung 2011] have
proposed a clustering algorithm for detecting future phenomena
based on the information extracted from text corpus, and
proposed a method of calculating the probability of an event to
happen in the future.</p>
      <p>Also, [Kanazawa et al. 2011] extracted unreferenced
future time expressions from a large collection of text, and
proposed a method for estimating the validity of the prediction
by searching for a real-world event corresponding to the one
predicted automatically.</p>
      <p>[Aramaki et al. 2011] used SVM-based classifier on
Twitter to perform classification of information related to
influenza and tried to predict the spread of the disease by using
a truth validation method.</p>
      <p>[Kanazawa et al. 2011] proposed a method for estimation
of validity of the prediction by automatically calculating
cosine similarity between predicted relevant news and searching
for the events that actually occurred.</p>
      <p>[Radinsky et al. 2012] proposed the Pundit system for
prediction of future events in news based on causal reasoning
derived from a similarity measure calculated using different
ontologies.</p>
      <p>[Jatowt et al. 2013] studied relations between future news
in English, Polish and Japanese by using keywords queried
on the Web.</p>
      <p>Recently, [Zhang et al. 2016] performed a variation
analysis of the evolution of technology for techniques to learn
causality relations from past events for the extraction of
features that cause future changes.</p>
      <p>The above findings have lead us to the idea that by using
expressions referring to the future included in newspaper
articles it could be possible to support human users in the
process of future prediction as one of the activities people
perform everyday. Moreover, by applying appropriate
reasoning algorithm, it could be possible to automatize the process
and create a system capable of automatic future prediction.
A method like that could have a number of applications in
various fields, such as in corporate management, trend
foresight, and preventive measures, etc. Also, as indicated by
previous research, when applied in real time analysis of
Social Networking Services (SNS), such as Twitter or Facebook,
it could also be helpful in disaster prevention or handling of
disease outbreaks.</p>
      <p>As for practical applications used in future trend
prediction, Stanford Temporal Tagger1 converts natural language
input such as “next Wednesday at 3pm” into particular
calendar based schedule such as “2016-02-17 T 15:00” depending
on the assumed current reference time. Similar is possible</p>
      <sec id="sec-2-1">
        <title>1https://nlp.stanford.edu/software/sutime.html</title>
        <p>with HidelTime2 [Stro¨tgen and Gertz] is as well.</p>
        <p>Methods like above, using time referring information, such
as “year”, “hour”, or more general “tomorrow”, etc., has been
applied before in extracting future information and retrieving
relevant documents. It has also been indicated that it is useful
to predict future outcomes by using information occurring in
present documents. A main difference with our research is
the fact that we focused not only on the explicit simple and
obvious patterns, such as time expressions, but on more
sophisticated expressions, combining both morphological and
semantic information, and automatically extracted such
morphosemantic sentence patterns.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Automatic Extraction of Future Reference</title>
    </sec>
    <sec id="sec-4">
      <title>Sentences</title>
      <p>In this section, we describe the method for extraction of future
reference sentences from news corpora.</p>
      <p>Future reference sentences include both explicit as well as
implicit expressions referring to the future. Explicit
expressions include e.g., future temporal expressions, or words and
phrases referring to the future (e.g. will , is expected to ,
plan to , etc.).</p>
      <p>However, many important sentences do not contain such
explicit expressions, but the information regarding future
outcomes is implicit. See the example below regarding the future
of America’s army troops dispatch to Afghanistan.
“He rejoiced to hear that President Obama had reemphasized the
need to focus on the War on Terror in Afghanistan, increasing the
likelihood of an early withdrawal of U.S. troops from Iraq.”
The sentence does not contain any future referring
expressions. Moreover, the sentence is in past tense (“rejoiced”,
“had reemphasized”), and therefore it is not possible to
specify that the sentence refers to the future by using standard
methods. Yet, the sentence clearly presents potential future
outcomes (“withdrawal of U.S. troops from Iraq”) with the
use of implicit information.</p>
      <p>The method proposed here deals with both explicit as well
as implicit information, such as above. It consists of two
stages. Firstly, the sentences are represented in a
morphosemantic structure [Levin and Rappaport Hovav 1998]
(combination of semantic role labeling and morphological
information). Secondly, frequent combinations of such patterns are
automatically extracted from training data and used in
classification.
3.1</p>
      <sec id="sec-4-1">
        <title>Morphosemantic Patterns</title>
        <p>In the first stage of the method, all sentences are represented
in morphosemantic structure (MS) for further extraction of
morphosemantic patterns (MoPs).</p>
        <p>The idea of MS has been described widely in linguistics
and structural linguistics. [Levin and Rappaport Hovav 1998]
distinguish morphosemantics as one of the basic type of
morphological operations on words, modifying the Lexical
Conceptual Structure (LCS) of a word.</p>
        <p>MoPs have been applied in analysis of an Indonesian
suffix –kan [Kroeger 2007], improving links between WordNet
Example I: Romanized Japanese (RJ): Ashita kare wa kanojo
ni tegami o okuru daro¯. / Glosses: Tomorrow he TOP her DIR
letter OBJ send will (TOP: topic particle, DIR: directional particle,
OBJ: object particle.) / English translation (E): He will [most
probably] send her a letter tomorrow.</p>
        <p>No. Surface</p>
        <p>Label
synsets [Fellbaum et al. 2009], or analysis of a Croatian
lexicon [Raffaelli 2013].</p>
        <p>Below we describe the process of morphosemantic
representation of sentences we applied in this research.</p>
        <p>At first, the sentences from the datasets (Japanese
newspaper corpora) are analyzed using semantic role labeling
(SRL), which provides labels for words and phrases
according to their role in sentence context.</p>
        <p>For SRL in Japanese we used ASA, a system which
provides semantic roles for words and generalizes their
semantic representation using an originally developed thesaurus
[Takeuchi et al. 2010]. An example of SRL provided by ASA
is represented in Table 1.</p>
        <p>However, not all words are semantically labeled by ASA.
The omitted words include, e.g., grammatical particles, or
function words not having a direct influence on the
semantic structure of the sentence, but in practice contributing to
the overall meaning. For those remaining words we used a
morphological analyzer MeCab3 in combination with ASA to
provide morphological information, such as “Proper Noun”,
or “Verb”. Moreover, as a post-processing procedure we
added a set of linguistic rules for specifying compound words
in cases where only morphological information was provided.</p>
        <p>Finally, for cases where the labels provided by ASA were
too specific (see Table 1), we normalized and simplified the
labels according to the following label priorities.</p>
        <p>1. Semantic role (Agent, Patient, Object, etc.)
2. Semantic meaning (State change, etc.)
3. Category (Dog ! Living animal ! Animated object)
4. In case ASA does not provide any of the above
labels, perform compound word clustering for parts
of speech (e.g., “International Joint Conference on
Artificial Intelligence” ! Adjective Adjective
Noun Preposition Adjective Noun !
Proper Noun)
4.1 If a compound word can be specified, output the
part-ofspeech cluster.
4.2 If it is not a compound word, output part-of-speech for
each word.</p>
        <p>Below is an example of a sentence represented in the
above morphosemantic structure.</p>
        <p>Romanized Japanese: Nihon unagi ga zetsumetsu kigushu
ni shitei sare, kanzen yo¯shoku ni yoru unagi no ryo¯san ni
2http://dbs.ifi.uni-heidelberg.de/index.php?id=129</p>
        <sec id="sec-4-1-1">
          <title>3http://taku910.github.io/mecab/</title>
          <p>kitai ga takamatte iru.</p>
          <p>English: As Japanese eel has been specified as an
endangered species, the expectations grow towards mass
production of eel in full aquaculture.</p>
          <p>SRL: [Object][Agent][State
change][Action][Noun][State change][Object][State change]
3.2</p>
        </sec>
      </sec>
      <sec id="sec-4-2">
        <title>Future Reference Pattern Extraction</title>
        <p>From sentences represented in morphosemantic structure we
extract frequent MoPs, by firstly, generating ordered
nonrepeated combinations from all sentence elements. In every
n-element sentence there is k-number of combination groups,
such as that 1 k n. Next, all non-subsequent elements
are separated with a wildcard (“*”, asterisk). Pattern lists
extracted this way from training sets are then used in
classification of test and validation sets.</p>
        <p>For all patterns generated this way their occurrences O are
calculated, and frequent (O 2) patterns are retained. Next,
the occurrences are used to calculate pattern weight. Two
features are important in weight calculation: pattern length k
(number of elements it contains) and its occurrence O (how
many times it occurs in the dataset) Thus in the experiments
we modified the weight by
awarding length (LA),
awarding length and occurrence (LOA),
awarding none (normalized weight, NW).</p>
        <p>The generated list of frequent patterns can be also further
modified. When two collections of sentences of opposite
features (such as “future-related vs. non-future-related”) are
compared, the list will contain patterns that appear uniquely
in only one of the sides (e.g., uniquely positive patterns and
uniquely negative patterns) or in both (ambiguous patterns).
Thus we also modified pattern lists by
using all patterns (ALL),
erasing all ambiguous patterns (AMB),
erasing only those ambiguous patterns which appear in
the same number in both sides (zero patterns 0P, since
their normalized weight is equal zero).</p>
        <p>Moreover, a list of patterns will contain both the sophisticated
patterns (with disjointed elements) as well as more common
n-grams. Therefore the system can be trained on a model
using
patterns (PAT), or
only n-grams (NGR).</p>
        <p>All combinations of the above modifications are tested in
the experiments.</p>
        <p>Examples of extracted MoPs of FRS and non-FRS with
their occurrences were shown in Table2.</p>
      </sec>
      <sec id="sec-4-3">
        <title>Future Reference Sentence Extraction with</title>
      </sec>
      <sec id="sec-4-4">
        <title>Morphosemantic Patterns</title>
        <p>From three newspaper corpora4 we collected and annotated
a dataset containing equal number of (1) sentences referring
to future events and (2) other (describing past, or present
events). We conducted an evaluation experiment with
training dataset containing 130 sentences each, furthermore as the
test data we used randomly extracted additional 170 sentences
from the news corpora.</p>
        <p>The test datasets were applied in a text classification task
with 10-fold cross validation. Each classified test sentence
was given a score calculated as a sum of weights of patterns
extracted from training data and found in the input sentence.
The results were calculated with Precision, Recall and
balanced F-score. We compared fourteen classifier versions. The
results indicated that the highest overall performance was
obtained by the version using pattern list containing all patterns
(including ambiguous patterns and n-grams). We looked at
top scores within the threshold, checked which version got
the highest break-even point (BEP) of Precision and Recall,
and calculated statistical significance of the results.</p>
        <p>Finally, we compared the proposed method to [Jatowt et
al. 2013], who extracted future reference sentences with 10
words explicitly referring to the future, such as “will” or “is
likely to”, etc. In comparison, the proposed method obtained
better results even when only 10 most frequent MoPs were
used (see Table 3 for details).</p>
        <p>Moreover, we verified the performance of the fully
optimized model. We retrained the best model using all sentences
from the initial training dataset and verified the performance
by classifying the new validation set. The final overall
performance was represented in Figure 1. Finally, the obtained
BEP was 0.76.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Future Prediction Support Experiment</title>
      <p>The validity of the method described in previous section
needs to be tested twofold. Firstly, by verifying the capability
of the method to provide a support for human users
performing a task of prediction of how a future event will unfold.
Secondly, by testing a fully automated process of prediction.</p>
      <p>In this section we present a validation experiment for the
effectiveness of using Future Reference Sentences in the task
of supporting human users in predictions regarding future
events.
4.1</p>
      <sec id="sec-5-1">
        <title>Experiment Setup</title>
        <p>In the experiment for supporting future trend prediction we
used the fully optimized model of FRS trained on MoPs
described in section 3.3. The model was applied to extract new
FRS concerning a specific topic, from the available
newspaper data. Such sentences were further called future
prediction support sentences (FPSS). Future prediction task was
performed by a group of thirty laypeople5, who were told to
read the FPSS and reply to questions asking them to predict
the future in 1–2 years from now, or from the starting point of
prediction.</p>
        <p>The questions were taken from the Future Prediction
Competence Test (FPCT, japanese: Senken-ryoku Kentei),
released by the Language Responsibility Assurance
Association(LRAA, japanese: Genron Sekinin Hosho¯ Kyo¯kai)6, a
nonprofit organization focused on supporting people of
increased public responsibility (managers, politicians) and
people responsible of making decisions influencing civic life. In
particular, the organization helps preparing public speeches
and responsibility bound presentations, by training
individuals in predicting possible outcomes of future events. A part
of this training consists of taking part in the FPCT.</p>
        <p>The FPCT is an examination that measures prediction
abilities in humans regarding specific events that are to happen
in 1–2 years in the future. It has been initiated in 2006 and
from that time it has been performed six times. The test
consists of various questions, including multiple choice questions
(e.g., “Will US Army contingent in Afghanistan increase or
decrease during next year?”), essay questions (e.g., “Describe
economic situation of a country after next two years”), and
questions that must be answered using numbers (e.g., “What
will be the exchange rate of Japanese Yen to US Dollar after
two years”), and they are scored after those particular events
have come to light.</p>
        <p>The questions for the experiment were selected from the
4th of the past six FPCTs, as it had the largest total number of
questions, and respondents, which would assure the highest
possible objectivity of the evaluation. Implemented in 2009,
the 4th FPCT contained questions regarding predictions for
2010 and 2011, and the scoring was performed in 2011.
Respondents were to choose to answer at least 15 questions from
a total of 25 questions in six areas, namely, politics,
economics, international events, science and technology, society,
525 males and 5 females, age groups from university students
studying computer science (28 user samples) to their fifties (2 user
samples).</p>
        <p>6http://genseki.a.la9.jp/kentei.html</p>
        <p>Question 3: Predict the stationing status
of US troops in Afghanistan at the end of
June 2011.
(A) The U.S. troops will be still present and
further reinforced comparing to October
2009.
(B) The U.S. troops will be still present on
similar level comparing to October 2009.
(C) The U.S. troops will be still present but
in decreased number comparing to October
2009.
(D) The U.S. troops will be completely</p>
        <p>withdrawn.</p>
        <p>Answer:
[ 1st candidate:
/ 3rd candidate
and leisure. The test contained a large number of multiple
choice questions and several questions requiring predicting
specific numbers. There was also a small number of
questions requiring a written explanation of the reasoning for the
prediction. When participating in the test, respondents can
browse any and all available materials, and are free to seek
opinions of others in answering the question, but the
submission deadline was fixed and set at December 31st, 2009 (end
of the year). The scoring is set at 90 total points on prediction
questions and 30 total points for descriptive questions, with a
total of 120 points.</p>
        <p>In the future prediction support experiment the developed
method extracts FPSS related to a given question and
provides assistance for human users on which answer to choose
during the test. Therefore for its evaluation we limited the
questions to multiple-choice questions. Questions with two
or more (multiple) possible answers were selected from the
4th FPCT and applied as questions for the experiment. One
of the questions was represented in Figure 2.
In this section we describe the process of data preparation for
the experiment. Firstly, a total of 7 multiple-choice questions
were selected from the 4th FPCT. Next, for each question we
extracted a number of FPSSs from news corpus to be read by
participants. Differently to the original settings of the Future
Prediction Competence Test, where the participants could
refer to any information and had the whole year to prepare their
answers, participants of our experiment were to only use the
provided FPSSs answer the questions at the time in the
experiment.</p>
        <p>The FPSSs for each question is collected in the following
steps. At first we extracted from the Mainichi Newspaper’s
entire 2009 year all sentences related to the questions on the
basis of topic keywords (Table 4), selected as nouns that
appeared in the original questions or answering options. We
also manually expanded search query by adding semantically
related keywords.</p>
        <p>The sentences were represented in morphosemantic
structure, analyzed using our fully optimized model, and sorted in
a descending order of resemblance to FRS. Next, we retained
only those FPSS which scores were over 0.0 and presented
the highest 30 of them to the subjects in chronological order
(date the sentence appeared in a newspaper), so the subjects
had a better image of how the events unfolded, which would
make the prediction more natural.</p>
        <p>The limit of thirty sentences was set so the subjects did
not become tired of the task. However, we kept the rest of
the sentences in case the subjects insisted on further reading.
In situations where the list of initial sentences extracted with
topic keywords was less than thirty, we presented to the
subjects all sentences which had a probability of being FRS.</p>
        <p>The questions were answered directly after reading only
the FPSS. Additionally, the laypeople were asked to report
the ID number of the FPSS they referred to in their answer
(or the FPSS considered as the most informative or useful).</p>
        <p>We evaluated their answers based on the original scoring
schema. In particular, each of the questions 1, 2, and 7 were
allocated up to 3 points. Moreover, in questions 2–5 the
laypeople were allowed to make up to three candidate choice
answers: primary, secondary and tertiary candidate, assigned
3, 2 points and 1 point, respectively.
4.3</p>
      </sec>
      <sec id="sec-5-2">
        <title>Experiment Results and Discussion</title>
        <p>The results of experiment were summarized in Table 5.</p>
        <p>In the performed experiment, the average score of the
experiment participants was 38.10% (see Table 5). In
comparison, in the original FPCT, the average score percentage of
the test participants was 33.44%. Therefore the results of our
experiment participants were slightly higher.</p>
        <p>One issue with the performed experiment was that the
questions for the prediction task were in fact past events
for the laypeople. Therefore, although the questions were
very specific, meaning it was not likely that the participants
knew or remembered the events, there was always a chance
that some of the experiment participants might have already
known the unfolding of the events in question and use this
knowledge in their advantage. Therefore just in case, we also
warned the experiment participants that in answering, they
should use only the knowledge provided in the FPSS.</p>
        <p>Although participants of our experiment obtained higher
scores than the participants of original test, the
improvement was not large. However, as the major contribution of
our method for future prediction support the following can
be considered. Even if we acknowledge that the
improvement was not sufficient, and that our subjects performed
similarly to original participants, our subjects made their
decisions based only on about thirty specifically extracted FPSSs
and were given only a short time for decision, whereas the
original participants had over one year term for preparing the
answer, unlimited access to all available data and receiving to
help from any other people including experts.</p>
        <p>It indicates that accurately extracted future reference
sentences are useful in prediction of future event unfolding for
people who have no knowledge regarding those future events.
Hence, supporting future prediction with FPSS for specific
topics can be considered at least as efficient as collecting
available information by oneself for one year time.
5</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Prototype Method for Automatic Future</title>
    </sec>
    <sec id="sec-7">
      <title>Prediction</title>
      <p>In this section, we describe and validate a prototype method
for prediction of future event unfolding. In the validation
experiment we aim to perform the previous task – described in
Section 4 – fully automatically.</p>
      <sec id="sec-7-1">
        <title>5.1 Method Description</title>
        <p>We developed the prototype method for automatic future
prediction to analyze the questions from the Future Prediction
Competence Test used in previous experiment. Although the
method can be adapted to analyze any content, in this research
we limited its functionality to the existing data to make the
evaluation possible and as objective as possible.</p>
        <p>The method consists of following steps.
1. Building an optimized model for Future Reference
Sentence (FRS) extraction (Section 3.3),
2. Extracting topic keywords from questions about future
unfolding of events (Section 4.2),
3. Applying the FRS extraction model and the topic
keywords to extract FRS related to question from a limited
corpus data,
4. Train a new event-topic-specific model on the extracted
topic-related FRS, using the method for Automatic
Extraction of Future Reference Sentences (Section 3),
5. Analyze answers to the each Question and choose the
one with highest score as the correct answer.</p>
      </sec>
      <sec id="sec-7-2">
        <title>5.2 Experiment Setup and Data Preparation</title>
        <p>We evaluated the performance of the prototype method for
automatic a future prediction. Originally, the evaluation task
was that laypeople were to read the automatically extracted
Future Prediction Support Sentences (FPSS) related to
Questions from the Future Prediction Competence Test (FPCT)
and to select those answers to the questions they considered
as correct using only the provided FPSS.</p>
        <p>The method for automatic prediction takes the human out
of the loop in the prediction task. Therefore in practice the
method would account for automatically reading through the
limited corpus and provide automatic inference regarding
answers to the FPCT questions based only on the automatically
learned information.</p>
        <p>In the evaluation, as the reference corpus for the method for
learning we applied the same newspaper corpus as in Section
3.3, but limited to one year, namely 2009, which presumably
contained news articles related to the questions.</p>
        <p>For each of the questions we used the extracted topic
keywords (Table 4) with the fully optimized model (Section 3.3)
to extract FRS related to each question. Next, the newly
obtained FRS were used as training data to train a new model
for each question. Finally, the newly created topic-oriented
FRS-based model was used to analyze the answers for each
question (see example in Figure 2) and the answer with the
highest score was selected as the correct one.</p>
        <p>Moreover, in order to analyze the influence of FRS on the
accuracy rate of correct answers, we developed two versions
of the prototype method.</p>
        <p>Ver. 1: Using for training thirsty or less FRS (condition
similar to the one under which experiment participants
performed the future prediction task in the future
prediction support experiment, explained in Section 4),
Ver. 2: Using for training all FRSs which scored over 0.98
(condition experimentally selected as optimal for
FRS, explained in Section 3.3).</p>
      </sec>
      <sec id="sec-7-3">
        <title>5.3 Experiment Results</title>
        <p>To put the developed prototype method in the same standpoint
as human participants, in evaluation of the prototype method
we adopted the same weighted scoring schema as in the
future prediction support experiment (Section 4.2). Namely, for
questions 1, 2, and 7 if the prototype method answered
correctly, it obtained 3 points for each question. Furthermore,
for questions 2–5 if the correct answer was selected by the
prototype method as either first, second or third candidate, it
was assigned 3, 2 points or 1 point, respectively.</p>
        <p>The results of the prototype method for each question were
shown in Table 6. An example of scoring of answers for two
questions (Q1-1 and Q3), for both versions of the prototype
method were represented in Table 7. For each question the
answer with the highest score is selected as the correct one.</p>
        <p>The version of the method using thirty FRS, obtained the
accuracy rate of correct answers 57.14%. It is an
improvement of over 20 percentage-points over the results obtained
by human participants.</p>
        <p>Additionally, although the the scores assigned by the
prototype method to each answer were different for both versions
of the method, there was no difference in final ratio of correct
answers between the version using thirty FRS or less, and all
FRS with over 0.98 of FRS-resemblance score (see Table 6).
Considering that the number of FRS used in training did not
influence the results, it could be more efficient to use the
version of the method using fewer number of sentences.
5.4</p>
      </sec>
      <sec id="sec-7-4">
        <title>Discussion</title>
        <p>In this experiment, we automatized the task of reading future
reference sentences and responding to future prediction
questions. The experiment results showed an improvement of over
20 percentage points of the developed prototype method over
human participants who took part in the prediction support
experiment. Moreover, the result was 23.7 percentage-point
higher than for average results of participants of the original
4th FPCT. In fact, with Accuracy on the level of 57.14% it
was very close to the highest results obtained by participants
of original test (61.11%) and our future prediction support
experiment (61.9%). Therefore we can clearly say that the
prototype method was nearly as good in predicting the
unfolding of future events as the best humans, and it was almost
twice as good as an average human, both using all available
resources and preparing their answer for a year, and using our
support method and making the prediction at the time of the
experiment. The final results were compared in Table 8. In
addition, when the correct answer was allowed till the third
candidate, the 5 out of 7 questions could be considered
correct, which gives a 71.43% of Accuracy, being over twice as
high as an average and over 10 percentage points higher the
best scoring human. Furthermore, if the tendencies of
correct answer rates for each question is compared between the
prototype method, and the future prediction support
experiment, the tendencies of correct and incorrect answers were
very similar, meaning, the inference resembles, and exceeds
human performance.</p>
        <p>The result was more than satisfactory, although we
acknowledge that there were many limitations imposed by the
controlled character of the experiment. Therefore we need to
convey additional experiments on other real world events to
obtain a clearer image of the capabilities of our method, most
desirably on events that in reality will unfold in future from
the time of the prediction.
6</p>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>Conclusions and Future Works</title>
      <p>In this paper we conducted two experiments to determine
whether Future Reference Sentences (FRS) are effective in
supporting future trend prediction by (1) laypeople and (2)
by a prototype fully automatic method. We applied questions
from the official Future Prediction Competence Test (FPCT)
and, using topic keywords from those questions, gathered
newspaper articles from the entire applicable year. Then we
extracted topic-related FRS from those articles, to be used in
predicting the unfolding of the events.</p>
      <p>In the results we obtained a small improvement over the
original FPCT. The original test allowed preparing answers
for over a year and using any available information. On the
other hand, participants of our experiment answered the
questions immediately after reading the provided support material
score average
Q-2 Q-3
3.00 1.00
1.36 2.36</p>
      <p>Q-4
0.00
0.27
which consisted of only thirty (or less) automatically selected
sentences. The time spent and the amount of information to
be processed for answering the future related questions was
greatly reduced with our support method. This indicates that
FRS are useful in supporting the prediction of future events.</p>
      <p>However, the most interesting discovery was made in the
experiments with the proposed prototype fully automatic
method for prediction of future unfolding of event, which
results showed that our prototype method exceeded even the
best humans in the prediction task and the average human
over two times. This provides a strong suggestion that full
automation of future prediction is possible.</p>
      <p>In the future, we plan to use this method with other
corpora to conduct experiments on real-world problems,
including various lengths of the term of prediction to specify to what
extent the method is applicable in future prediction. Also,
carrying out a chronological analysis of FRS and the addition
of sentiment analysis could lead to the discovery of additional
new knowledge. We also plan to take part in the next FPCT.</p>
    </sec>
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