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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Exploring dynamic embeddedness: a network analysis of the global pharmaceutical industry 1991-2012</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Elio Shijaku</string-name>
          <email>elio.shijaku@uab.cat</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Martin Larraza-Kintana</string-name>
          <email>martin.larraza@unavarra.es</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ainhoa Urtasun-Alonso</string-name>
          <email>ainhoa.urtasun@unavarra.es</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Dept. de Empresa, Universitat Autònoma de Barcelona</institution>
          ,
          <addr-line>Catalonia</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Dept. de Gestión de Empresas, Universidad Pública de Navarra</institution>
          ,
          <addr-line>Pamplona, Navarre</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>We analyze the global pharmaceutical industry network using a unique database that covers strategic transactions (i.e. alliance, financing and acquisition collaborations) for the top 90 global pharmaceutical firms and their ego-network partnerships totaling 4735 members during 1991-2012. The network evolution is traced via a novel method based on the concept of dynamicity that quantifies individual network members (i.e. actors) contribution to the longitudinal period. Specifically, we observe dynamic embeddedness defined for key network centrality measures, and capture the impact of the 2007-2008 global financial crises and the subsequent global and Eurozone recession effects on the strategic transaction flows between the industry's key players as well as their partners. Results suggest the feasibility of dynamicity as a dynamic network indicator as well as the importance of constellation strategic transactions in the study of large network perturbations.</p>
      </abstract>
      <kwd-group>
        <kwd>longitudinal social network</kwd>
        <kwd>strategic transaction</kwd>
        <kwd>dynamicity</kwd>
        <kwd>dynamic embeddedness</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Organizations are inherently embedded actors of social networks, whose
structures evolve dynamically, and as a result of each actor’s involvement
offer important clues on organizational strategic behavior. Inside a dynamic
network, organizations exist as highly mobile entities with their relationships
and positional structures continuously changing in time. As such,
understanding organizational behavior involves first and foremost capturing
organizational dynamics often done by analyzing the longitudinal context where
network dynamics is observed. While most literature on longitudinal
networks focuses on a more holistic evolution of their structure [
        <xref ref-type="bibr" rid="ref11 ref2 ref4">2, 4, 11</xref>
        ], more
recent studies have highlighted the contribution of each actor to the overall
network dynamics [
        <xref ref-type="bibr" rid="ref1 ref6">1, 6</xref>
        ]. This actor-level approach embodied by the concept
of dynamicity, relies on the assumption that capturing organization’s
dynamic behavior in a given network should be based on a combined analysis of
both static and dynamic network topologies [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Additionally, dynamicity
enables researchers to study the effect of specific critical events (i.e.
perturbations) that greatly alter the structure of the panel network.
      </p>
      <p>
        However, quantifying actor involvement and contribution in
longitudinal networks, and modeling its behavior against specific perturbations has
been limited, with research confined to the effect that organizational crisis
has had on organizational communication networks [
        <xref ref-type="bibr" rid="ref13 ref6">6, 13</xref>
        ]. These few
available longitudinal network studies on actor contribution have analyzed
network dynamic evolution relying on embeddedness, a well-known concept in
social network analysis, long considered a highly strategic resource with
important impacts on firm’s performance [
        <xref ref-type="bibr" rid="ref5 ref8">5, 8</xref>
        ]. On this matter, network
literature has often relied on centrality-based embeddedness to provide a
dynamic image of social network evolution [
        <xref ref-type="bibr" rid="ref14 ref9">9, 14</xref>
        ].
      </p>
      <p>
        Furthermore, the majority of research on embeddedness has
approached the concept from a dyadic (i.e. a group consisting of only two
actors) perspective, bypassing multiple types of firm interaction. Even those
studies that focus on the so-called constellation (i.e. interactions between
more than two actors) perspective [
        <xref ref-type="bibr" rid="ref3 ref7">3, 7</xref>
        ], miss out at the relevance of actors
engaging in constellation ties of multiple kind, by considering only a single
type of collaboration. Additionally, embeddedness’ studies have focused
heavily on strategic alliance collaborations, a choice well-grounded by the
interorganizational collaborations in any given industry, but that often fails
to embrace the full picture of strategic interactions’ multitude.
      </p>
      <p>We fill these shortcomings by focusing on longitudinal networks
generated from strategic transactions, a conceptualization of interorganizational
collaborations engaged by a firm with its network partners including
strategic alliances, acquisitions and financing collaborations, analyzed under both a
dyadic and constellation lens. By doing so, we contribute not only to the
literature of alliance collaborations but enhance the currently undernourished
network literature on acquisition and financing collaborations as well which
play an important role in the dynamics of strategic organizational behavior.</p>
      <p>Our study addresses the above gaps by developing and testing a
theoretical framework that links the concepts of dynamicity, embeddedness and
strategic transactions. By doing so, we uncover the dynamic evolution of the
global pharmaceutical industry chosen for its intensive collaboration
environment. Given the novel nature of dynamicity as a concept, we attempt to
examine some fundamental questions that develop a theory-based
understanding of dynamicity and its relationship with embeddedness, as well as
analyze the impact that strategic transactions have on such structure: How
does dynamicity of centrality measures evolve in a longitudinal network?
What is the role of strategic transactions in the evolution of such dynamicity?
How does actor´s dynamicity behave in the presence of exogenous events
that critically alter the network structure?</p>
      <p>
        Specifically, we expand the actor-level approach on dynamic networks
by introducing the concept of dynamic embeddedness, defined as the
individual actor’s central position variability in a longitudinal network setting
compared to its central position variability in a aggregated network. For the
purpose of this paper, our focus is exclusively on the dynamicity of structural
embeddedness and particularly on the dynamicity of key network centrality
measures such as degree, betweenness and closeness. Specifically, we build
on a dynamicity model [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] by exploring the critical impact that large
exogenous perturbations, such as the 2007-2008 financial crisis, the subsequent
2008-2009 global recession and the more local Eurozone recession of
20112013 have on longitudinal networks between top-level actors and their ties
in the global pharmaceutical industry.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Data and measures</title>
      <p>We conduct our analysis on a longitudinal dataset (t = 22 years, 1991-2012)
comprising the strategic transactions of 90 leading firms from the
pharmaceutical industry in Western Europe, United States, Asia, Africa and Australia.
The sample is selected by identifying those firms that appear at least once in
the top 50 of the Pharmaceutical Executive Magazine yearly editions for the
period 2002-2013. We then use the Pharma and Medtech Business
Intelligence database to collect all the strategic transactions that involved the
firms in question from 1991 to 2012. During this period, the 90 firms of the
sample engaged in alliance, financing and acquisition collaborations with
4645 other firms and institutions creating a total of 12055 strategic
transactions.</p>
      <p>Due to our selection process, we consider two types of firms, the core firms
comprised of the top 90 pharmaceuticals and the periphery firms including
the rest of the actors, with a total population of 4735 firms whose full list is
available from the authors. The obtained longitudinal data for both core and
periphery firms presents missing actors, since some firms are acquired by
others, or simply are not active for any particular year. Our analysis also
includes financial data obtained from COMPUSTAT and DATASTREAM
databases, supplying missing data when possible using company annual reports.
Since the financial data concerns firms from different countries, we convert
all currencies to USD with an exchange rate based on the particular year the
data is retrieved.</p>
      <p>
        We model each year over the sample period as a separate social
network and analyze each network based on a similar approach for the
global banking network analysis [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]: (i) the core network, referring to the ties
between the top 90 actors; and (ii) the full network comprising all available
data from a total of 4735 actors. In our analysis, we consider a weighted
undirected tie approach, defined as an N x N “weight” matrix, whose generic
entry wij = wji &gt; 0 measures the interaction intensity between any two actors
(zero if no link exists between actor i and j). Following this framework and
using the software R, we build 22 symmetric 90 x 90 matrices to track the
evolution of the core network and 22 symmetric 4735 x 4735 matrices to
track the evolution of the full network for the period 1991-2012.
Additionally, for dynamicity calculation purposes, we build two matrices which include
the aggregated strategic transactions of the entire 22 years period for both
types of network.
      </p>
      <p>
        Network indicators. The network measures of our analysis include
three centrality variables (degree, betweenness and closeness centrality) and
the dynamicity variable representing the variability of the structural positions
of an actor in all short-interval networks compared to its structural position
in the aggregated network [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] as shown in equation 1:
      </p>
      <p>m</p>
      <sec id="sec-2-1">
        <title>DDAi</title>
        <p>
          t
where DDAi is the degree of dynamicity shown by ith actor, OVAN is the
observed value (i.e. degree centrality) for the aggregated network, OVt is
the observed value (i.e. degree centrality) for tth yearly network for the ith
actor, m is the number of yearly networks considered in the analysis, and
t,t 1 is a constant valued according to whether the actor is present or
missing in the current and previous short-interval network. The presence of this
constant is of crucial important to properly count for actors that disappear
from the network due to simple inactivity or possible lack of presence due to
network dynamics. The possible combination values that t,t 1 can take are
For the first short-interval network (i.e. i,0 for t = 0) of our analysis, the
value of the constant depends on the presence or absence of each actor (i.e.
either 0 or 1) at that particular period. The dynamicity model [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]
differentiates between two types of dynamicity measures, the dynamicity of an actor
represented by equation 1 and the average dynamicity shown by an actor of
the tth short-interval network represented by equation 2:
wt
t,t 1
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>OVAN OVt wt</title>
        <p>where DDN t is the average degree of dynamicity shown by an actor of the
tth short-interval network meaning the contribution of each actor to the
short-interval network´s dynamicity, and wt is the total number of actors in
the tth short-interval (i.e. yearly) network. Therefore, our analytical approach
is based on three variables: degree dynamicity, betweenness dynamicity and
DDN t
t
(2)
closeness dynamicity constructed by substituting each obtained centrality
value to equations 1 and 2.</p>
        <p>Industry indicators. In order to analyze the effect of exogenous
critical events such as financial crises and recessions on the global
pharmaceutical industry, we construct two main effect variables: (i) global crisis
representing the combined effect of the 2007-2008 financial crisis and the global
recession of 2008-2009 that followed as a direct consequence, and
constructed as a dummy variable that takes the value of 1 for the years
20072009 and zero for the rest, and (ii) local crisis representing the exogenous
effect of the Eurozone recession during 2011-2013, and constructed as a
dummy variable that takes the value of 1 for the years 2011-2012 and zero
for the rest.</p>
        <p>Control indicators. We use several actor-specific measures such as
strategic transaction frequency, R&amp;D intensity, profitability, headquarters
(HQ) location and financial leverage age and size. Strategic transaction
frequency represents the relative frequency in percentage with which firms
engage in strategic transactions. In the analysis, we differentiate between
the frequency in percentage of firms engaging in alliance, financing and
acquisition collaborations. R&amp;D intensity represents the firm’s R&amp;D
expenditure scaled by total sales while profitability is measured for each firm by
computing the ratio of net income to total assets (ROA). We define financial
leverage as the debt-to-total assets ratio including both short- and long-term
debt and control for the age of the firms, operationalized as the foundation
year minus the year considered in the 2002-2012 panel analysis, and size
operationalized as the natural logarithm of company’s employees. Finally,
since our data consists of multinational firms and knowing that the majority
of the top 90 firms are US- or EU-based, we control for headquarters (HQ)
location based on two separate dummy variables representing whether firms
are U.S. or EU-based.</p>
        <p>Model approach. By using a two-step approach to our analysis, first
we assess the stability of dynamicity distributions in selected years to
capture statistical differences throughout our data using Kolmogorov-Smirnov
(henceforth, KS) tests for both core and full networks, second by controlling
for firm-specific effects, we investigate the effect that the global crisis
(including the 2007-2008 financial crisis and the great 2008-2009 recession),
and the local crisis referring to the Eurozone recession, observed for
20112012, have on degree, betweenness and closeness dynamicity. For our
second step, we run a panel regression model based on random effects
(henceforth, RE) with robust estimations based on the model seen below:</p>
        <p>Yit k X it i uit it , i 1,..., 90, t 1,...,10,
where Yit is firm´s dynamic embeddedness considered as a dependent
variable, X it is a vector of firm and industry-specific independent variables
including global and local crises, age, size, profitability, financial leverage, R&amp;D
intensity, transaction frequency and firm location, i is the unknown intercept
for each firm, uit is the between-firm error, it is the within-firm error, k is
the coefficient for each k independent variable, i is the number of firms (90
in total) and t is period of time considered (10 years in total or +/- 5 years
window before and after the offset of the 2007-2008 financial crisis).
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Results</title>
      <p>We describe the dynamics of the global pharmaceutical industry using four
key estimates: (i) tracking dynamic embeddedness evolution based on
average dynamicity estimate plots, (ii) monitoring the stability variation of actors’
dynamic embeddedness based on KS-tests, (iii) constructing the top five firm
rankings based on yearly network average dynamicity estimates, and (iv)
understanding the global and local crises causative effect on dynamic
embeddedness based on panel regression estimates. Results (i) – (iii) concern
the total panel period 1991-2012 while results (iv) concern the panel period
2002-2012.</p>
      <p>
        We track dynamic embeddedness evolution by plotting the
crosssectional averages of dynamic indicators during 1991-2012 as seen in Figure
1. Both panels show that dynamicity values present relative stability before
2007 for degree centrality but vary substantially for betweenness and
closeness centrality throughout the study period. Specifically, for the core
network, degree and betweenness dynamicity drop respectively 20 percent and
17 percent while closeness dynamicity is almost halved by 40 percent during
the global crisis. The more local Eurozone crisis of 2011-2013 (of which we
analyze only one year due to sample structure) shows a similar pattern with
both networks’ dynamicity severely reduced. An exception is closeness
centrality, whose dynamicity shows an upward trend for the core network, with
signs of a more clustering-oriented tendency.
We monitor the stability of both core and full networks by comparing the
dynamicity distribution in the first year of each decade including last
available year’s data (1991, 2001 and 2012) with subsequent years in the same
decades, a procedure seen in global banking network analysis [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] and
whose results are given in Table 2.
      </p>
      <p>Table 2. Empirical distribution stability for dynamic embeddedness
Looking at the main effects of the regression analysis, we observe the
negative effect of the global crisis on dynamicity indicators except degree
dynamicity, for which the effect is not significant, meaning that the combined
effect of the 2007-2008 crisis and the subsequent global recession of
20082009 have not significantly affected the number of strategic transactions
originating from each of the core network members. Moreover, we find
strong statistical significance for the negative effect that the local Eurozone
crisis has had on firms’ dynamic embeddedness. Additionally, the type of
strategic transaction is found to influence dynamic embeddedness. This
effect is understandable considering the relatively high distribution of alliance
transactions in the sample (about 75 percent). However, the positive and
significant effect of acquisition transactions on degree dynamicity is
interesting considering that both acquisition and financing transactions show similar
distributions in the sample (about 12.5 percent each). Finally, the observed
low R-squared is not necessarily a drawback for the chosen model
particularly if we consider that the results present statistically significant predictors
and the regressors are used in a panel setting.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Discussion and concluding remarks</title>
      <p>With respect to the analyses’ objective, the results on firm´s dynamic
embeddedness suggest that prior to the global crises the global pharmaceutical
industry has been relatively stable, with firms’ centrality reflecting their
market position. Specifically, the top pharmaceutical firms that rank high in
terms of sales have a noticeable central position in both core and full
networks as observed in the firm rankings. Dynamically speaking, the global
pharmaceutical industry has reduced its activity to even lower levels than the
beginning of our sampling data, year 1991. While the reduction varies for
specific centrality measures, its effect is more prominent after 2007, which
coincides with the offset of the 2007-2008 financial crises. The regression
results confirm this by showing significant dynamicity reduction during both
crises. Furthermore, the regression results indicate that the Eurozone
recession has had a far deeper negative effect on global pharmaceutical industry
than the global recession.</p>
      <p>This study also highlights the importance of acquisition transactions in
the expansion of the firms’ importance as central hubs. Specifically, the
significant effect of acquisitions on degree dynamicity demonstrates the impact
that different strategic transactions have on centrality indicators and further
reinforces the reasoning behind our choice to study the centrality measures
evolution via the dynamicity concept. However, this also raises questions as
to why comparable effects of strategic transaction types (i.e. acquisitions and
financings) respond differently to centrality-based dynamicity.</p>
      <p>Our study’s limitations could potentially provide interesting areas of
future research. First, we should be careful when generalizing our results
about the global pharmaceutical industry, knowing that not all firms in both
core and periphery networks are dedicated to pharmaceuticals but come
from other adjacent industries such as biotechnology and chemicals. Second,
dynamicity measure calculation is based on a novel design which takes into
account missing actors during network evolution using a specific constant
which should be subject to further research for proper values’ assignment.
Finally, the dynamicity measure could be used for other centrality measures
(i.e Eigenvector, Bonacich Power) or be included in the analysis of network
measures such as actor’s structural similarity, structural holes and brokerage
elasticity.</p>
      <p>Acknowledgments. The authors wish to acknowledge the financial support
provided by the Spanish Ministry of Science and Education under projects
ECO2010-21393-C04-01 and ECO2013-48496-C4-4-R.</p>
    </sec>
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