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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>An Analysis of Novelty Dynamics in News Media Coverage</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Ronaldo Cristiano Prati</string-name>
          <email>ronaldo.prati@ufabc.edu.br</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Walter Teixeira Lima Junior</string-name>
          <email>contato@walterlima.net</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Univerisdade Federal do Amapa</institution>
          ,
          <addr-line>Macapa, Amapa</addr-line>
          ,
          <country country="BR">Brazil</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Universidade Federal do ABC, Santo Andre</institution>
          ,
          <addr-line>Sa~o Paulo</addr-line>
          ,
          <country country="BR">Brazil</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2016</year>
      </pub-date>
      <abstract>
        <p>Computer Science has a ected almost all elds of human knowledge, contributing to scienti c advances in many branches of Natural and Social Sciences. Journalism is one of the elds that is bene ting of the advance of computer science. Among the journalistic concepts that can be analyzed computationally is News Value. Novelty is one of the most important news value. A possible approach to get novelty elements in a story considers word frequency, through of the capacity to collect and analyze massive amounts of data. In this paper, we use the News Coverage Index dataset (NCI), maintained by the Pew Research Center, to analyze the novelty dynamics of news coverage, using the novelty signatures proposed by [12]. As a de nition of novelty, we used the rst appearance of a new lead newsmaker. Results show a good t of the model to the dataset. Furthermore, an analysis by media sector and broad topic shows interesting insights for the analysis of media coverage.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The Computational Science has a ected almost all
elds of human knowledge, contributing to scienti c
advances in many branches of Natural and Social
Sciences. For instance, the capacity to collect and analyze
massive amounts of data has transformed intensely
elds such as biology and physics [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>
        In Social Science, despite the di culties to formalize
computationally many scienti c subjects of the human
behavior, \a computational social science is
emerging that leverages the capacity to collect and
analyze data with an unprecedented breadth and depth
and scale" [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Unfortunately, most of the advances
in this area have been progressing at a much slower
pace. However, substantial barriers that might limit
progress are being overcome in recent years. The
emergence of a powerful new eld of data analysis of Social
Science has also in uenced the research on a branch of
it, Journalism. Journalism is an important social
practice. Therefore, to nd non-trivial information on
content produced by journalism, it is necessary to count
with the support of the current stage of technologies
to advance in analytical techniques \Computation can
advance journalism by drawing on innovations in topic
detection, video analysis, personalization, aggregation,
visualization, and sense making [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>
        Among the journalistic concepts that can be
analyzed computationally is News Value. News value as
a concept was thought by Johan Galtung and Mari
Holmboe Ruge's seminal publication in the Journal of
Peace Research. In 1965, the paper suggested a range
of attributes that establish news values in discursive
elements contained in newspapers and broadcast news.
Galtung and Ruge established the news values
elements as Frequency; Threshold; Unambiguity;
Meaningfulness; Consonance; Unexpectedness; Continuity;
Composition; Reference to Elite Nations; Reference to
Elite People; Reference to Persons; and Reference to
Something Negative [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. These factors have been the
base to compose the structure of the theory of
newsworthiness. The theory is based on the psychology of
individual perception and explain which factors in
uence newsworthiness of an event [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
      <p>
        News values are studied considering a range of
attributes contained in discursive elements. It is also
possible to verify the news value through a range
of \more speci c cognitive constraints that de ne
news values (Novelty, Regency, Presupposition,
Consonance, Relevance, Deviance and Negativity,
Proximity) [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The news value named Novelty can be
analyzed by words such as reveal or revelation. These
words announce semantically `unexpected aspects of
an event News stories are frequently about
happenings that surprise us, that are unusual or rare' [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
      </p>
      <p>
        The novelty can be understood by concepts as out
of the ordinary, least expected, or not predicted, news
values relating to the novelty, newness or
unexpectedness of an event/happening [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The quality of being
interesting enough to the public (newsworthiness) is
also based on if a journalistic fact is out of the
ordinary, it will have a greater e ect than something that
is an everyday occurrence (unexpectedness). The
unexpectedness power of attraction is in the factor that
\there is new information that has been uncovered
and evaluations of importance can make the eliteness
of a source explicit" [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. This means that readers
or viewers can know facts or di erent people or
unusual to their quotidian, however, \this is the old
manbites-dog syndrome which needs little more
explanation" [
        <xref ref-type="bibr" rid="ref2 ref9">9, 2</xref>
        ]. When a fact or term rst come up, the
human attention is captured, but \the fact that the
novelty of a story tends to fade with time and thus
the attention that people pay for it. This can be due
to either habituation or competition from other new
stories" [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>
        As previously observed, novelty is also elaborated
\mainly through using evaluative language, references
to surprise/expectations and comparisons" [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. This
way of perception of novelty on the construction of
journalistic contents is based on analyzes produced by
reading the news. However, it is possible to get
novelty elements in the story considering word frequency,
through the capacity to collect and analyze massive
amounts of data. Over the years, there is a massive
increase in the availability of journalistic data and
creation of new tools to extract the value from data that
are helping to understand our lives, organizations, and
societies.
      </p>
      <p>In this paper, we used a recent model of novelty
dynamics to analyze news coverage. The main idea
is to analyze whether di erent news sources present
di erent novelty dynamics. This paper is organized
as follows: Section 2 presents novelty signatures that
emerge in some dynamical processes. Section 3
describes the data set used in our study. Section 4
presents the results of applying the novelty signatures
to the NCI dataset, and Section 5 concludes the paper.</p>
    </sec>
    <sec id="sec-2">
      <title>Novelty in dynamical processes</title>
      <p>
        Tria et. al [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] have recently analyzed novelty as new
events occurring in a dynamical process evolving over
time. Given a sequence of events, a novelty occurs
whenever a new element rst appears in a sequence.
They have analyzed four di erent data sets: books
from Gutenberg project Corpus, annotations in the
social bookmarking platform Delicious, songs and singers
at Last FM streaming portal and, entries appearance
in English Wikipedia. The novelties in these data are,
respectively, the occurrence of new words in books, the
use of new annotation tags in the bookmarks, the
inclusion of a new artist/song in a play list the user had
never listen to and the rst edition of a page in the
collaborative encyclopedia.
      </p>
      <p>
        They were able to model novelty as a simple
mathematical model based on random draws sampling with
replacement of an Urn [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] that increases when a novel
item is observed. The model predicts statistical laws
for the rate at which novelties happen (Heaps' law [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ])
and for the probability distribution on the space
explored (Zipf's law [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]), as well as signatures of the
process by which one novelty sets the stage for another.
      </p>
      <p>The rst signature is based on quantifying the rate
at which novelties occur in a temporally ordered
sequence of elements of length N by analyzing the
growth of the number D(N ) of distinct elements in
this sequence. This relation would imply in a Heap's
law, which states that the rate at which novelties
occur decreases over time as t , where is the coe cient
of a power law distribution of D(N ) over N tted over
the data.</p>
      <p>The second signature is related to the frequency
of occurrence of di erent elements in the data. The
frequency-rank distribution would follow an
approximate Zip an distribution (Zipf's law). In this
distribution, the frequency of any element is inversely
proportional to its rank in the frequency table, i.e., the
frequency F (R) of an element at rank R is
proportional to R , where is the coe cient of a power
law distribution of F (R) over R tted over the data.</p>
      <p>
        It is well known that and are inversely
correlated [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. The larger the coe cient, the higher
the frequency of appearance of new elements in the
sequence, thus there is a high propensity for novelty.
On the other hand, the larger the coe cient, the
higher the occurrence of the most frequent elements in
the sequence. The key result reported in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] is that
in the four data sets analyzed, the model was able to
capture the novelty behavior in the data. An
interesting research question is then whether News delivery
also shows these novelty signatures. This paper is an
initial attempt towards such analysis.
      </p>
    </sec>
    <sec id="sec-3">
      <title>News Coverage Index dataset</title>
      <p>In our analysis, we used the data gathered by the Pew
Research Center1. Every week, this institution
produced the News Coverage Index (NCI) by identifying
and annotating the main subjects covered by the U.S.
mainstream media. The dataset used this research is
the most updated dataset (2013), published by Pew
Research Center. Until this moment, no other similar
dataset that can be used to update the data or serve
to comparison.</p>
      <p>
        The NCI captured and analyzed 52 news
outlets in real time to determine what was
being covered and what was not in the U.S.
news media. The analysis was conducted
weekly, Monday - Sunday. The key variables
included source, story date, big story, broad
story topic, placement, format, geographic
focus, story word count, duration of
broadcast story and lead newsmaker. The outlets
studied came from print, network TV, cable,
online, and radio. They included evening and
morning network news, several hours of
daytime and prime time cable news each day,
newspapers from around the country, the top
online news sites, and radio, including
headlines, the long form programs and talk [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>By focusing on the topic of the story, the index
measures by what percentage of the analyzed news hole is
about that topic. Data were collected from January
2007 to May 2012. Table 1 presents the number of
news stories collected per year. Note that the year
2012 has a few stories because the collection period
ranges from January to May, rather than January to
December.
The codebook includes variable names, de nitions,
applicable procedures and changes that were made to
certain variables. For each story, it was annotated
the date, source, broadcast start time (morning, noon,
afternoon, evening and night, or not broadcast),
duration in seconds, word counts, placement prominence,
story format, big story, geographic focus (local, US
national, US international, non-US international), broad
1Formerly Project for Excellence in Journalism (PEJ).
story topic, media sector (cable TV, network TV,
newspaper, online and radio), and lead newsmaker.
The number of outlets and individual programs vary
considerably within each media sector, as do the
number of stories and size of the audience.</p>
      <p>The index is a good source for analyzing, through
time, how stories emerge and sink. Other
possibilities include how the character or narrative focuses of
the story change and how much of the broad topic's
categories get more coverage, when compared to the
others. However, the index does not provide
information for additional possible questions, such as tone,
sourcing or other matters.</p>
      <p>The key variable chosen in this study was \lead
newsmaker", a variable that \determines the person
whose actions or statements constitute the main
subject matter of the story". In the NCI, the derivation
of the \lead newsmaker' variable used a methodology
that examined the outlets daily by the coding team.
The researchers establish as a de nition: variable lead
newsmaker determines the person whose actions or
statements constitute the main subject matter of the
story discussed with at least 50% of the story (in time
or space).</p>
      <p>Therefore, in our analysis, a news story is agged as
a novelty whenever the rst appearance of a new lead
newsmaker occurs, considering an ordered sequence of
histories by date in the NCI. Obviously, this approach
does not completely capture all the aspect of novelty
in news coverage. It is perfectly possible (and indeed
very common) that some new factor is being published
by some lead newsmaker who appeared before.
However, this approach does capture some aspect of
novelty, in a sense that di erent subjects are being noticed
in the media. Furthermore, the approach sheds some
interesting insights, as discussed next.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Results and Discussion</title>
      <p>
        In this section we present the results of the novelty
signatures as proposed by [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] to the NCI dataset. As
the main variable used in this study was lead
newsmaker, we removed from the dataset all stories where
the lead maker was not identi ed, resulting in a total
of 135,205 entries in the dataset.
      </p>
      <p>
        Figure 1 shows the two novelty signatures for all
stories in the NCI dataset, for the Heaps' law and Zipf's
law, respectively. The graphs show a very good t (the
blue line in the graphs), indicating that the dynamic
of novelties also follows the model proposed in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] for
the NCI dataset.
      </p>
      <p>This is an interesting result per se, but we can move
beyond that by conditioning the analysis by some news
groups. Figure 2 does this, where we have split the
analysis by the media sector (newspaper, online, radio,
101
102
103
104
105
0
10000
Analysis by Media Sector</p>
      <p>MediaSector</p>
      <p>CableTV β=0.76
NetworkTVβ=0.85
ROandlinioe ββ==00..8830
Newspaper β=0.83
40000
MediaSector</p>
      <p>CableTV α=1.07
NetworkTVα=0.98
ROandlinioe αα==00..9927
Newspaper α=0.89
104
103
broadcast TV and cable TV). Figure 2(a) shows how
novel lead newsmakers appears in the news sequence,
for each media sector collected by the NCI. The
interpretation of these results is, the steeper the line, the
more novelty the media sector has (according to the
de nition of novelty used in this paper). Surprisingly,
newspapers is the media</p>
      <p>sector with the larger ratio of lead newsmakers per
story, followed by online portals, radio, network TV
and cable TV. Figure 2(b) shows an orthogonal
insight for this result, which shows the rank distribution
of lead newsmakers for each sector. As Heaps' law
and Zipfs' law are inverse correlated, the
interpretation of these results are, the steeper the line, the more
a media sector concentrates the coverage in a few lead
makers. Cable TV repeats lead newsmakers more
often than other sectors, and (proportionally) uses fewer
leads newsmaker than the other media sectors.
Newspapers, on the other hand, proportionally use the top
ranked lead news makers less often, and have a larger
number of histories with di erent lead makers.</p>
      <p>We can speculate that the higher frequency of novel
lead newsmakers in newspaper media is due to that
this media needs competitiveness in relation to other
media (digital and electronic), which are characterized
by dissemination of news in real time. As the
newspaper is a diary media, it always needs to have
something di erent to present than what was published on
the previous day on TV, radio and, Internet. Despite
being late in relation to events in one day (it
generally publishes stories from the eve), the newspaper still
continues to be a source for other rival media because
it intends always having something new in their pages.
On the other hand, TVs have a rotating audience, and
focus on a narrow range of topics. Thus, the presented
histories focus in a few lead newsmakers. Radios an
online media are somehow in between these two
extremes.</p>
      <p>To gain some insight in the online versus o ine
scenario, we break down the analysis in online versus
ofine media, as shown in Figure 3. The interpretation
of the graphs is the same as of 2. Figure 3(a) shows
that online sector introduce more lead makers in their
stories, and Figure 3(b) indicate that the same lead
maker appears less often in online media. As can be
seen from the graphs, online media have stronger
novelty signatures. Therefore, online media have a bias
towards introducing more di erent lead newsmakers,
and a lower tendency to echo the same leading maker
in future stories.</p>
      <p>A possible reason for this is that online outlets have
a high propensity to show new stories due to the di
erence in media consumption from the target audience.
In general, the audience for online news sources is of
younger people (as discussed in the previous section).
These users have a less tendency to in-depth stories,
foComparison of online versus non−online media
Analysis by Broad Story Topic
102
f)(
R
101
0
20000
10000
cusing in the headlines. They also are more connected,
and access the news more often, thus the necessity of
novelty in the news stories.</p>
      <p>We did a similar analysis, but conditioning on the
ve most frequent broad story topics. The broad story
topic variable identi es which of the broad topic
categories is addressed by a story. NCI has 32 broad
story categories, but most of them have low
frequencies. These low frequencies di cult an analysis, due
to a lack of data. Figure 5 shows these results. The
interpretation of the graphs is the same as of 2, except
for the fact that instead of media sectors, we have
topics in these graphs. Figure 4(a) shows how novel lead
newsmakers appear in the news sequence, for each of
the ve most frequent topics collected by the NCI. In
these gures, one traditional attribute of news value,
Negativity (any reference that is negative), emerges as
through Crime broad story topic. Crime is the topic
with the largest rate of novel lead makers, followed
by economy/economics, US foreign a airs, government
agencies/legislatures and campaigns/elections/politics
with the lowest rate. Figure 4(b) indicates that the
most frequent lead makers appear proportionally less
often in the news than the most frequent lead makers
in campaigns/elections/politics. Furthermore, crime is
the sector with the largest proportion of lead makers
to appear in fewer histories.</p>
      <p>A similar analysis was performed by start time of
the program, as shown in Figure 6. The
interpretation of the graphs is the same as of 2, except for the
fact that instead of media sectors, we have the
program start time in these graphs. Figure 5(a) shows
that, in general, morning programs introduce more
often new lead makers, while night programs have few
novelty lead makers. On the other hand, Figure 5(b)
shows that night program cites more often the more
noticed lead makers than morning programs. We
believe this also is related to the target audience, which
in the evening/night has a higher prevalence of elderly
people, which is more interested in-depth coverage.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Concluding Remarks</title>
      <p>
        In this paper, we examine the dynamic of novelties in
the NCI dataset. We used the lead newsmaker as the
main variable to de ne the concept of novelty in our
framework. We veri ed a very good t of these data
to the two novelty signatures discussed in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
      </p>
      <p>We obtained interesting and insightful insights
when conditioning the analysis do media sector and
broad story topic. Regarding media sector, we
veried that newspapers is the sector with largest novelty,
in terms of the introduction of new lead
newsmakers. Furthermore, online media have a largest novelty,
when compared to non-line media. In terms of story
topic, crime is the sector with more novelty, also in
terms of lead newsmakers.
6000
)(4000
ND
(a) Heap's Law
101
102R</p>
      <p>We believe these patterns somehow tend to follow
the interest of the public in order to get her attention.
Thus, there is the necessity to provide news on topics
to better reach a target audience, tailoring the
audience. An interesting future work is to analyze whether
these patterns would be similar in the next years,
because the online young audience became a generation
more mature. Would the behavior be the same, and
the sectors have to adapt to the news consumption
patterns of this generation or they will change their
tastes, showing a similar behavior or their previous
generation as accessing the in-depth stories?</p>
      <p>This research has two obvious limitations. First,
our adopted de nition of novelty does not capture all
aspects of novelty, as new information can be
published about lead Newsmakers which already appeared
in the sequence. However, we believe this de nition do
capture some aspects of novelty, and were able to
provide some interesting insights on the topic.
Furthermore, the data set has a bias towards the U.S.A. media
coverage. An interesting further research direction is
to broaden this research to di erent sources.</p>
    </sec>
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