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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Personality Mining from Biographical Data with the “Adjectival Marker ” Technique</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Shivani Poddar</string-name>
          <email>shivani.poddar92@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>VenuMadhav Kattagoni</string-name>
          <email>venumadhav.kattagoni@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Navjyoti Singh</string-name>
          <email>singh.navjyoti@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Center for Exact Humanities</institution>
          ,
          <addr-line>IIIT Hyderabad</addr-line>
        </aff>
      </contrib-group>
      <fpage>39</fpage>
      <lpage>47</lpage>
      <abstract>
        <p>The last decade has witnessed significant work in personality mining from lexical cues in social media data. Not much work has yet been undertaken in extracting these lexical cues from biographical data populating social media. Most of this work involves a large crowd of researchers leveraging dictionary-based approaches such as LIWC (which primarily focus on function words). By means of this paper we intend to introduce a novel method of personality mining from social media data called “Adjectival-marker Technique”. This method involves extracting lexical features from descriptive texts (e.g. biographical data) to train a learning model, so as to predict the respective personality traits of the subject. Conceptually, it draws heavily from the last 78 years of work in lexical psychology and the Big Five personality test. However, it is not only a computational variant of the primordial theories of lexical psychology, but is also competent in conferring a substantial accuracy of personality prediction, matching that obtained by psychometric tests. In this study, we propose a variant of the Lexical Hypothesis from psychology. This modified hypothesis is validated by the computational results of personality prediction achieved by the Adjectival Marker Technique discussed below. The paper also discusses some insights illustrating the coherence of people's judgments about the subject's personality (virtual personality). The average accuracy (i.e. matching that achieved by psychometric tests for Big 5) for prediction approximated to Extraversion - 82.82% Agreeableness - 89.62%, Conscientiousness 92.48% and Imaginativeness/Intellect - 81.67%.</p>
      </abstract>
      <kwd-group>
        <kwd>Social Computing</kwd>
        <kwd>Psychology</kwd>
        <kwd>User Personality Determination</kwd>
        <kwd>Natural Language Processing</kwd>
        <kwd>Machine Learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1.1. Motivation</title>
      <p>
        Social Media has become the most abundantly used means
of communicating and propagating information online.
Most information here is extensively descriptive of the
users who channel themselves through it. It is not only the
user who gives away information about himself
        <xref ref-type="bibr" rid="ref11">(Goldbeck
et al, 2011)</xref>
        , but also his peers (Staiano et al, 2012). This
paper mainly unravels how the latter approach is nearly an
absolutely accurate predictor of certain personality traits.
The judgements of not only peers but of people who know
us remotely over time can be an important window into
solving the labyrinth of our personalities. The future of
social media will witness individuals choosing workplaces,
friends, books, movies, products etc, in synchrony with
their own personalities. The tomorrow of the advertising
industry will witness a transformation from “spammers” to
“personalized suggestors”. This has also been cited in
various discussions wherein advertisers are advised to study
personalities instead of demographics (documented in the
paper personalized persuasion,
        <xref ref-type="bibr" rid="ref16">(Jacob, 2012)</xref>
        ). The
aforementioned applications are just a tip of the iceberg.
Relationships have been discovered between personality and
psychological disorders, job performance
        <xref ref-type="bibr" rid="ref8">(Digman et al,
1990)</xref>
        and satisfaction
        <xref ref-type="bibr" rid="ref19">(John et al, 1990)</xref>
        , and even
romantic success. An extremely dynamic field of study which also
benefits from the research in the area of Human Computer
Interaction (HCI) is interface design. Many interface
designing projects revolve around modelling interfaces based
on people's personality oriented preferences. This study,
thus, aims to contribute to bridge this gap between
biographical data and personality research. We also attempt
to expedite the process of personality prediction, making it
more automated instead of relying heavily on psychometric
tests written by the subject.
      </p>
    </sec>
    <sec id="sec-2">
      <title>1.2. The Big Five Personality Model</title>
      <p>
        There have been several personality models (The Big
Three, The Big Five, The Alternative Five, etc.) that claim
to encapsulate the traits that need to be summoned so as
to effectively predict user personalities from social media
data. However, out of all these models, the most robust
and tested model, which has been consistent for the last
few decades, is the Big Five (Big5) model
        <xref ref-type="bibr" rid="ref13">(Goldberg et
al, 1992)</xref>
        . This personality model, being one of the most
supported in lexical psychology research, stood out as
being most resilient to carry out research of biographical
social media resources
        <xref ref-type="bibr" rid="ref34">(Saucier et al, 1996)</xref>
        . Another one
of the instrumental personality theories that has spawned
the landscape of personality models is the set proposed
by Carl Jung (Myers-Briggs Type Indicator (MBTI),
Socionics, Kiersey et al, 1921). Following the paucity of
data (for evaluating our model) available for personality
determination via reliable psychometric tests for the Big 5
model, we decided to refer to a publicly published research
dataset,1 that abundantly provided us with the MBTI
personalities for people. So as to bridge this gap between the
MBTI (for personalities which needed to be used for
evaluation) and Big 5 (the personalities which were being
predicted by our model), (Capraro et al (2002), Furnham et al
(1996), McCrae et al (1989)) we used correlations shown
in Tables 1 and 2. Thus, one of the major motivations of
this paper is also to draw the most effective traits (namely:
Extraversion, Agreeableness, Conscientiousness and
Imaginativeness) from the intersection of these two instrumental
1The dataset can be found at http://www.celebritytypes.com.
paradigms of personality qualifiers. Hence, in scope of this
study, the traits we predict are Extraversion, Agreeableness,
Conscientiousness and Imaginativeness/Intellect.
      </p>
    </sec>
    <sec id="sec-3">
      <title>1.3. Motivation for using Biographical Data</title>
      <p>
        This research builds on the confluence of two major
domains, the primordial theories of the lexical hypothesis and
the recent computational techniques of data modeling.
Allport's personality trait names
        <xref ref-type="bibr" rid="ref1">(Allport et al, 1936)</xref>
        lead to
the creation of Goldberg's adjective marker
        <xref ref-type="bibr" rid="ref13">(Goldberg et
al, 1992)</xref>
        and have ignited various studies.
        <xref ref-type="bibr" rid="ref12">Goldberg et al
(1990</xref>
        ), Digman et al (1990), John et al (1990),
        <xref ref-type="bibr" rid="ref30">Ostendoff
et al (1990</xref>
        ) built on the same foundation. All of these
converge at a single point that cites a “descriptive”, “adjectival”
lexicon to be the key into a person's personality. Social
media today is littered with biographical or descriptive content
of its over 1.4 billion users. Tapping this reservoir of
content by the principles and techniques discussed below, the
paper aims at unveiling a substantial part of this personality
descriptive content.
      </p>
    </sec>
    <sec id="sec-4">
      <title>1.4. Proposed modification in the “Lexical Hypothesis of Psychology”</title>
      <p>The theories of psychology were influenced by various
revolutionary concepts, for instance, “trait” - a theoretical
construct which describes a basic dimension of a person's
personality (Allport, 1937). The idea of trait gave birth to the
“Lexical Hypothesis of Psychology”. The initial direction
of this paper was solely governed by this exact hypothesis
(worked upon by Klages, 1926/1932; Cattell, 1943;
Norman, 1963; Goldberg, 1982)</p>
      <p>“Those individual differences that are most
salient and socially relevant in people's lives will
eventually become encoded into their language;
the more important such a difference, the more
likely is it to become expressed as a single</p>
      <p>
        word.”
The Lexical Hypothesis has been used in its entirety in
author's personality prediction systems, like the one for Greek
Language described by Kermanidis et al, (2012). Motivated
by the same inspiration, we too expected to extract author's
personality traits from the text they wrote. This involved
mobilizing huge datasets of web blogs and essays and
extracting “names” from them to determine the author's
personalities. However, by the course of our study, we found
out that this was not as effective as the initial hypothesis
proposed (Goldberg et al, 1982). The average accuracy of
the initial experimentation was less than 50%, which was
as good as a randomly predicted personality set.
Thus, we propose a modification of the Lexical
Hypothesis in psychology which suggests that the personality of a
person is predicted based on cumulative judgements of
various authors about him/her. These judgements are
indicative of the respective traits of the person described along
the lines of the Big5 personality Model. The “Adjectival
Marker ” Technique helps us unravel these judgements, and
is derived from the adjectival markers of Big5 personality
traits as discussed by Goldberg &amp;
        <xref ref-type="bibr" rid="ref34">Saucier (1996)</xref>
        . Thus, the
modified Lexical Hypothesis of Psychology proposed and
verified in this paper is as follows:
      </p>
      <p>“Those individual differences that are most
salient and socially relevant in people's lives will
eventually (over time) become encoded into their
language as well as that of people who describe
them (via the knowledge they have of them, these
people could be peers, associates, friends, family
members, followers etc.); the more important
such a difference, the more likely is it to become
expressed as a single word”.</p>
      <p>The “Adjectival Marker Technique” introduced in this
paper is most accurate when it is used to analyze the
personality of the subject who the social media resource is
descriptive of and not the author himself. We also inferred an
interesting observation that suggested that the views of different
people describing the subject are coherent amongst
themselves and also with the results of the psychometric tests.
The average accuracy of the traits, based on the proposed
hypothesis, for a series of data spread temporally and
spatially (as compared to the results obtained by psychometric
tests) in social media came out as discussed below.</p>
    </sec>
    <sec id="sec-5">
      <title>1.5. Structure of the Paper</title>
      <p>We begin by presenting a brief background on the Lexical
Psychology theories of personality determination and
related work on personality in conjuction with social media
in Section 2. We then present our dataset in Section 3 &amp; 4
and methodology for analyzing, quantifying and modelling
biographical data content for 574 personalities in Section
5. The study proceeds on to describe the adjectival features
used along with the machine learning techniques for
classification and demonstrate significant improvements that the
model was able to achieve over baseline classification on
each personality factor. In subsequent sections, the paper
presents the results in Section 6 and analysis of the study,
and discusses the methods we incorporated which were
instrumental in escalating the accuracy of the model for each
of the traits discussed earlier in Section 7. We finally wrap
up the paper with brief discussions about the future work,
sparked by this study in Section 8.</p>
      <p>2.</p>
      <sec id="sec-5-1">
        <title>Related Work</title>
        <p>The last few years have witnessed a considerable
escalation in studies which are directed at mining user
personalities from social media data. Those which are related to
this work can be mined in mainly 2 sections. (i) Studies
which are based on lexical cues to mine author's
personality, (ii) Studies which have used social media based features
to study the personality of the user.</p>
        <p>
          The former section includes work by Tausczik and
Pennebaker (2010) wherein they mined author personality via
LIWC (Linguistic Inquiry and word count) approaches.
Another such study used linguistic features such as
function words, deictics, appraisal expressions and modal verbs
to classify 2 of the Big Five traits namely neuroticism and
extraversion
          <xref ref-type="bibr" rid="ref2">(Argamon et al, 2005)</xref>
          .
          <xref ref-type="bibr" rid="ref29">Oberlander &amp; Nowson
(2006)</xref>
          classified extraversion, stability, agreeableness and
conscientiousness of blog authors' using n-grams as
features and Naive Bayes algorithms.
          <xref ref-type="bibr" rid="ref25 ref26">Mairesse et al, (2007</xref>
          )
reported a long list of correlations between Big5 personality
traits. They obtained those correlations from psychological
factor analysis on a corpus of Essays and audio cues
          <xref ref-type="bibr" rid="ref31">(Pennebaker &amp; King 1999)</xref>
          to develop a supervised system for
personality recognition.
          <xref ref-type="bibr" rid="ref24">Luyckx et al, (2008</xref>
          ) built a corpus
for stylometry and personality prediction from text in Dutch
using n-grams of Part-Of-Speech (POS) and chunks as
features. They used the MBTI schema in place of the Big5
(it includes 4 binary personality traits, see
          <xref ref-type="bibr" rid="ref4">Briggs &amp; Myers
(1980)</xref>
          ). Along the same lines,
          <xref ref-type="bibr" rid="ref15">Iacobelli et al, (2011</xref>
          ) used
as features, word n-grams extracted from a large corpus of
blogs, testing different extraction settings, such as the
presence/absence of stop words or inverse document frequency.
They found that bi-grams, treated as Boolean features and
keeping stop words, gave substantial results using Support
Vector Machines (SVM) as learning algorithm.
          <xref ref-type="bibr" rid="ref23">Kermanidis
(2012)</xref>
          followed
          <xref ref-type="bibr" rid="ref25 ref26">Mairesse et al, (2007</xref>
          ) and developed a
supervised system for POS tagging in Modern Greek, based
on low level linguistic features, such as Part-of-Speech tags,
and psychological features, like words associated to
psychological states like in LIWC.
          <xref ref-type="bibr" rid="ref23">Kermanidis (2012)</xref>
          also
somewhat operated along the lines of Lexical Hypothesis
by mining author personalities via KMeans clustering
algorithms.
        </p>
        <p>
          Personality Analysis in Social Media Analysis is a recently
observed phenomenon. Herein, some substantial work was
done by Goldbeck et al, (2011) wherein the authors
predicted the personality of 279 users from Facebook, using
either linguistic or social network specific features.
          <xref ref-type="bibr" rid="ref32">Quercia
et al, (2011</xref>
          ) used network features to predict the personality
of 335 Twitter users, using M5 rules as learning algorithm.
Various means of evaluation have been used by the above
researchers, ranging from accuracy to AUC (Area Under
the Curve) values so as to establish relative accuracies of
models against each other. The above have been discussed
and captured very effectively by
          <xref ref-type="bibr" rid="ref7">Celli et al, (2013</xref>
          ). One
important observation which comes to surface while
analyzing relevant literature is that, none of the studies so far have
exploited the primordial lexical hypothesis and 'adjectival
traits' suggested by Saucier et al, (1996). Our work
presented in this paper carves a very different niche for itself
by computing this very approach of personality adjectives,
compressing the last 80 years of psychological research in
the lexical front and merging it with the latest
computational techniques. This confluence has yielded encouraging
results, predicting traits matching those predicted by a
psychometric test.
        </p>
      </sec>
      <sec id="sec-5-2">
        <title>Datasets</title>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>3.1. Biographical Data Mobilization</title>
      <p>The data collected as a part of this study was by means of a
Python-based crawler. We first used a simple web crawler
to get a list of web-pages with the name of the respective
“person” as the argument keyword to the crawler. These
web pages were then filtered based on their meta-tags. To
boost true positives, we only considered the pages which
specified their content as “biographical” in the meta-tag
descriptors. This resulted in mobilization of few Wikipedia
resources, blog mentions and majorly some very
descriptive biographical websites. We then manually cleaned the
noisy data to assure entity disambiguation and irrelevant
mentions. The same has been illustrated by means of
Figure 1.</p>
    </sec>
    <sec id="sec-7">
      <title>3.2. Personality Traits Data</title>
      <p>
        The Jungian Personality functions of 574 personalities were
extracted from the resource for eventual evaluation.2 Since
this was one of the most authentic reserves we found
consisting of personality listings (so as to evaluate the ones our
model predicts) we found it the most effective to be used
for evaluating our own model. The “Adjectival Markers”
that the paper is based on (as described below) are a proven
indicator to reflect the Big5 traits of personality. Thus, to
evaluate our computed predictive model via personalities
for the respective subjects by an exclusively listed source,
we scaled the Jungian Typology type to the closest traits of
the Big5 using correlation factors as shown in Table 2
        <xref ref-type="bibr" rid="ref10 ref14 ref27 ref5">(Hall
et al. 2009, Capraro et al. 2002, Furnham et al. 1996,
McCrae et al. 1989)</xref>
        . Table 1 shows the supporting notations
of the personality systems.
      </p>
      <sec id="sec-7-1">
        <title>Big5/ Global5</title>
      </sec>
      <sec id="sec-7-2">
        <title>Jung/MBTI/Kiersey</title>
      </sec>
      <sec id="sec-7-3">
        <title>Strength of</title>
        <p>Correlation</p>
      </sec>
      <sec id="sec-7-4">
        <title>High Very Low High</title>
      </sec>
      <sec id="sec-7-5">
        <title>Extraversion</title>
        <p>Emotional Stability
Conscientiousness
Accommodation /
Agreeableness</p>
        <p>Intellect</p>
      </sec>
      <sec id="sec-7-6">
        <title>Introvert/Extrovert Feeling/Thinking Judging/Percieving</title>
      </sec>
      <sec id="sec-7-7">
        <title>Feeling/Thinking</title>
        <p>Sensing/Intuition</p>
      </sec>
      <sec id="sec-7-8">
        <title>Medium Medium-High</title>
        <p>As illustrated, 4 final personality traits were scaled (each
of which had medium to high correlation with the MBTI
2http://www.celebritytypes.com, wherein extensive cognitive
functions have been used to derive the psychology of the given
personalities.</p>
        <p>Semi-Correlating Descriptions
Jung/MBTI/Kiersey Global 5</p>
      </sec>
      <sec id="sec-7-9">
        <title>INFP</title>
        <p>
          INTP
INFJ
INTJ
ISTJ
ISFJ
ISTP
ISFP
ENFP
ENTP
ENFJ
ENTJ
ESTJ
ESFJ
ESTP
ESFP
The adjectives mined from the biographical data were
refined to extract the adjectival markers i.e. specific
adjectives descriptive of the subject of the biographical data.
These adjectival markers were used as features in the final
LASSO logistic regression model. The adjectival markers
extracted are based on the work of
          <xref ref-type="bibr" rid="ref34">Saucier &amp; Goldberg,
(1996)</xref>
          . Table 3 provides the factor loadings of few of the
435 adjectives
          <xref ref-type="bibr" rid="ref34">(Saucier et al, 1996)</xref>
          on each of the five
factors as discussed in their work. The order reflects the
relative size (variance) of the factors (e.g. Factor II is the
highest), and the sign reflects the relative size of the item subsets
at each pole of the factor (e.g. the negative pole of Factor
IV has more items). We have, as a part of our study,
condensed this table to solely indicate whether or not the trait
is descriptive of a particular trait, so as to achieve a binary
matrix for them (for the respective 4 of the Big 5 traits
mentioned above). The binary equivalent for Table 3 is shown
in Table 4.
        </p>
        <sec id="sec-7-9-1">
          <title>Biographical Data</title>
          <p>Biographical data was mined for 574 personalities from
online resources as discussed in the former Section 3.1. This
data was divided into 2 categories. Testing data and
Training data. Users with no substantial data (&gt;100 words were
discarded for the analysis as of now). The data mining
undertaken for acquiring these datasets is spread across
various social media resources including Wikipedia articles,
blog posts, social Q &amp; A sites and community media sites
(sharing biographical book excerpts, for building datasets
of word count &gt;10,000)</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>4.1. Training Data</title>
      <p>The training data set, used to mine adjectival markers,
comprised of biographic data content of 283 personalities. The
word count of the dataset ranged from 500 - 10,000 words.
The ratio of the number of adjectives to the total number of
words in the dataset ranged from 0 to 0.005.</p>
      <p>This data content was mined by means of a Python-based
web crawler, which parsed biographic websites, Wikipedia,
and social media mentions.</p>
    </sec>
    <sec id="sec-9">
      <title>4.2. Biographical Testing Data</title>
      <p>The testing dataset comprised of biographic data content
of a different set of 291 personalities than the ones used
for training. These were mined from the social media
reserves like Wikimedia articles, blog posts about the
respective personalities, social Q&amp; A sites etc. The word count
and the number of adjectives to the total number of words
ratio ranged from 100 10,000 words and 0.0001 to 0.003
respectively.</p>
      <sec id="sec-9-1">
        <title>Adjectives*</title>
      </sec>
      <sec id="sec-9-2">
        <title>Sympathetic Kind Sensitive Rude</title>
        <p>Adventurous</p>
        <p>
          II
The training data (283 users) was mined for
adjectival markers according to Saucier's adjectival marker list
          <xref ref-type="bibr" rid="ref34">(Saucier et al, 1996)</xref>
          . Personality traits and their adjectival
markers were represented as a sparse User-Trait Adjective
Matrix for each of the 4 adjectival traits to be predicted. The
entries of the respective Trait (say T) matrix were set to 1 if
there existed an adjectival marker in the user's descriptive
biographical data and 0 if the respective adjectival marker
was not there. Thus, each personality trait was contained
in a matrix wherein the Row of the matrix M, consisted
of adjectival-features and the corresponding column entry
consisted of the User-trait. The matrix entity Mij was a
binary number which was 1 if the adjectival marker in the ith
row indicated the presence of the trait T in the personality
of the subject contained in the jth column of the Matrix M.
To predict the binary score of a given personality feature,
we then performed a LASSO logistic regression
(Tibshirani et al., 1996, Meier et al., 2008) analysis in Weka
          <xref ref-type="bibr" rid="ref14">(Hall
et al., 2009)</xref>
          . A variety of regression algorithms were tested,
each with a 10-fold cross-validation with 10 iterations. The
best result out of all algorithms was using a binary classifier
with Lasso regression (with 10 fold cross validation).
Using the LASSO Technique ensured that there was no
overfitting because of extra adjectival features for certain
traits.
        </p>
        <p>Since there was only single source where traits of
major personalities are classified (i.e. celebritytypes.com) we
used it to evaluate our model. We used the remaining 291
personalities for evaluation of the model. The testing
biographical data was mined for adjectival trait markers and
their respective traits were predicted. The results of this
evaluation have been discussed elaborately in the next
section. Figure 2, which can be found above, is also illustrative
of the procedure define above.</p>
        <sec id="sec-9-2-1">
          <title>Results</title>
          <p>
            The results by the above illustrated method are elaborated
in this section. The average accuracies compared to the
personalities obtained via psychometric tests (discussed in
more detail in the following section) for considered four of
the Big 5 traits were: Extraversion - 82.82% Agreeableness
- 89.62%, Conscientiousness - 92.48% and
Imaginativeness/Intellect - 81.67%. These readings do not necessarily
demonstrate the prediction accuracy of the innate
personality of a person but match that predicted by the psychometric
tests with the given accuracies. They are also in league with
few other techniques predicting the same for instance, the
work of
            <xref ref-type="bibr" rid="ref15">Iacobelli et al, (2011</xref>
            ) attempted to decipher the
personalities of bloggers has an average personality
prediction accuracy of around 62.5%.
          </p>
          <p>Thus, this paper proposes a technique which illustrates
mainfold elevation in the overall accuracy of personality
prediction (as indicated by psychometric tests) via social
media.</p>
        </sec>
        <sec id="sec-9-2-2">
          <title>Discussion</title>
          <p>The results obtained illustrate that this method is
competent for predicting the personalities of a person in
coherence with other people's judgments about him/her. It gives
substantial accuracies in the prediction of a person's
personality matching with those obtained via psychometric tests.
As an essential part of this study, we have also attempted to
capture the variation in accuracy with the change in
various factors, namely, word count of the corpus, and the
ratio of the number of adjectives to the total number of
words.3 These are mainly intended to explore a threshold
for word count and the adjective distribution (for the given
3Please note that the accuracies discussed here are the
accuracy of the prediction as evaluated by the results via psychometric
tests for Big 5 and should not be confused with accuracies used for
predicting the baseline of the universal personality of a person.
technique) in the document set so as to get substantial
results from the Adjectival Marker Technique. The following
deductions can be made respective to each trait:
7.1.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-10">
      <title>Collective Observations</title>
      <p>Few collective observations can be drawn from the
gathered data. As indicated in Figure 4, the accuracy in
predicting the traits increases with an increase in the data word
count. We also compared the accuracy results in predicting
the respective traits on the basis of varying distribution of
adjectives in the training dataset (Figure 5). The accuracy
in predicting the traits is relatively low when the ratio of the
AC/TWC is low and increases with a subsequent increase
in the AC/TWC ratio.
7.2.</p>
    </sec>
    <sec id="sec-11">
      <title>Agreeableness</title>
      <p>The accuracy in predicting Agreeableness is relatively low
(73.33%) for data with word count &lt; 5000 words, and
escalates up to 99.11% for big data reserves (&gt;20,000
words). We also compared the accuracy results of
predicting “Agreeableness” on the basis of varying distribution of
adjectives in the training dataset.</p>
      <p>The prediction of the “Agreeableness” trait is relatively low
when the ratio of the adjectival count versus total word
count is low. It illustrates an accuracy of 84.00% when the
ratio is less than 0.001, improving to 94.18% when the
ratio is between 0.001-0.002. Finally it escalates to 95.62%
when increased to be greater than 0.003 (Figure 5). As
expected there is a consistent increase in accuracy with
increase in word count and the ratio AC/TWC.
7.3.</p>
    </sec>
    <sec id="sec-12">
      <title>Conscientiousness</title>
      <p>The accuracy in predicting Conscientiousness varies from
86.66% when the word count of the data reserves is less
than 5000 words, and subsequently increases with the
increase in the number of words as shown in Figure 4.
We also varied the adjective distribution with the word
count so as to obtain respective accuracies for the same
model. It varies from an accuracy of 88.00% when the
ratio is less than 0.001, improving to 93.60% when the ratio is
between 0.001-0.002, and finally to 95.44% when increased
to be greater than 0.003 (Figure 5). As expected there is a
consistent increase in accuracy with increase in word count
and the ratio AC/TWC.</p>
    </sec>
    <sec id="sec-13">
      <title>7.4. Imaginative</title>
      <p>The accuracy in predicting Imaginativeness varies from
93.33% at wordcount lower than 5000 words, and goes upto
99.88% for big data reserves (Figure 4).</p>
      <p>The peaks observed in the variation of accuracy for
“Imaginative” trait over the distribution of adjectives (AC/TWC)
range from 85.71% accuracy for AC/TWC = 0.001, 90.69%
accuracy for AC/TWC = 0.002 and finally 98.42% for
AC/TWC &gt;= 0.003 (Figure 5).</p>
    </sec>
    <sec id="sec-14">
      <title>7.5. Extraversion</title>
      <p>The accuracy varies from 97.70% for word count &lt; 5000
words and subsequently increases to 99.88% as shown in
Figure 4.</p>
      <p>The accuracy of this trait varied from 85.71% for AC/TWC
= 0.001 and went on to increase upto 99.68% for AC/TWC
= 0.002 and then 99.70% for AC/TWC &gt;= 0.003.
The correlations for each of word count with
accuracy and AC/TWC with accuracy for each of the above
mentioned coefficient implies that for “Adjectival Markers”
these are highly correlated to one another. This can also be
validated by the graph in Figure 6.</p>
      <sec id="sec-14-1">
        <title>Conclusion &amp; Future Work</title>
        <p>
          By means of this study we propose a simpler yet
effective method to facilitate personality extraction of people
in social media. In order to achieve this we have also
reworked some perennial theories of Lexical Psychology and
modified them with the newer concepts of machine
learning models. This technique brings about a wave of novelty
in the wide spread lexical concepts and techniques used to
achieve user personality understanding in biographical data
reserves. It is a significant contribution in the field of
Computer Human interaction, since it is not just based on the
modern model training techniques of artificial intelligence,
but also finds solid ground in the foundational theories of
human psychology. One major drawback of this study is
that, it is (as of now) most optimized and accurate when
tested on bigger data samples. This research is thus
intended to pave way for extrapolating itself to smaller data
reserves and microblogs. We intend to apply the same
technique on not just adjectives but various other parts of speech
(POS) in the near future. There are various studies which
discuss the role of a person's personality in the development
of diseases
          <xref ref-type="bibr" rid="ref9">(Friedman et al, 1987)</xref>
          . Thus, another goal that
this research aims to achieve is that in the very near
future it would be able facilitate personality analysis for a
wide range of people with varied handicaps which render
them incapable of self-analysis in order to effectively
predict their personalities. Statistics say that 11% of children
4-17 years of age (6.4 million)
          <xref ref-type="bibr" rid="ref9">(Friedman et al, 1987)</xref>
          in the
United States itself have been diagnosed with
AttentionDeficit / Hyperactivity disorder (the number increasing by
3% this year). With valuable feedback from friends and
family this model can help designing better technology for
them and various other such people. Building upon this
research and extending it to cover other POS would enable us
to predict personalities from scanty as well as large datasets
with good accuracy. The vision of this research is to train
our next generation computers to not only understand
people in terms of their choices, but the innate personalities
which lead them to make those choices (leading to smart
suggestive advertising systems etc). The future work of this
research will also include combining this technique with
pre-existing ones (e.g. LIWC, etc.) so as to increase the
personality prediction accuracy to match that achieved by
psychometric tests. We also intend to work on a lexical
personality ontology, which analyzes the relationship of
personality (both direct and indirect) with the various parts of
speech (POS) i.e. extending it from being solely adjectival
markers to various other POS. We would soon be
graduating from solely Big5 trait prediction to evolving various
mental states which can be predicted from the abundant
lexical resources available online. Thus graduating the singly
dimensioned Big5 model to a multi-dimensional graphical
ontology tree of a person.
        </p>
      </sec>
    </sec>
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