Brokerage & Structural Holes

Structural Holes

• Basic idea: Lack of ties among alters may benefit ego

• Benefits • Autonomy

• Control flow

• Information nexus

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Structural holes vs. Closure

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Control Benefits of Structural HolesQuickTime™ and a

TIFF (LZW) decompressorare needed to see this picture.

Access to Information & Success

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Changes Made

•Cross-staffed new internal projects •white papers, knowledge base development

•Established cross-selling sales goals •Managers accountable for selling projects with both kinds of expertise

•New communication vehicles •project tracking db; weekly email update

•Personnel changes

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9 months later

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Entrepreneurial Network

•sparse, flat structure •independent relations,sustained by manager

•structural holes, low redundancy provides info & control benefits

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Entrepreneurial Network

• Associated with successful managers• and Machiavellian politicians :-)

• Places heavy cognitive load on the manager

• Enemy of a friend needs to be your friend…

• Stress relief either through institutionalization and rules or through embracing an egalitarian network

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Fragility of Structural Holes

• Side nodes are marginalized• Marginalization breeds discontent• Requires aggressive maintenance

• Up to use of force

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Support Network

•dense, flat structure •self-sustaining interdependentrelations

•few holes, high redundancy creates social support

• self-sustaining ties, development ofan internal culture

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Support Network

• “Organic structure” spreads the load over larger number of people

• Increased coordination costs

• Reduced managerial ability• (but reduced need for management)

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Ingroup/Outgroup

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

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Political Ties in the Caucasus

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Burt’s Measures of Structural Holes

• Effective Size• Constraint

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Effective Size

• Number of non-redundant ties in an ego network• How many actors is ego connected with

that are not connected to each other?

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Political Ties in the Caucasus

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Political Ties in the Caucasus

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Political Ties in the Caucasus

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Effective Size

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Effective Size in Binary Data

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Embassy Network

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Constraint

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Embassy Network

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Brokerage Roles

• Broker is the middle node of a directed triad

• What if nodes belong to different organizations?

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Brokerage Roles

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Brokerage within organization

• Organizations can be divided into clusters

• Any way of partitioning that produces interpretable results for a given network• n-cliques, n-clans, k-plex

• Find nodes that bridge gaps between partitions

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Real data…

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Counting Role Structures

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Role Profiles

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In embassy network

• Partitioned using 2-clans 1 2 3 4 5 6 Coord Gate Rep Cons Liais Total ------------------------------------------------------------- 2 Khalfan_Khamis_Mohamed | 0 0 0 0 0 0 | 4 Ahmed_the_German | 0 0 0 0 0 0 | 6 Wadih_al_Hage | 6 7 7 4 0 24 | 8 Ali_Mohammed | 0 0 0 0 0 0 | 10 Mohammed_Salim | 0 0 0 0 0 0 | 12 al-Fawwaz | 0 0 0 0 0 0 | 14 abouhalima | 0 0 0 0 0 0 | 1 Mohammed_Rashed_Daoud_al-O | 0 0 0 7 0 7 | 3 Mohammed_Sadiq_Odeh | 0 0 1 0 0 1 | 5 Fazul_Abdullah_Mohammed | 0 0 0 0 0 0 | 7 Usama_Bin_Ladin | 0 3 3 2 6 14 | 9 Ahmed_Khalfan_Ghailani | 0 0 0 0 0 0 | 11 al-Fadl | 0 0 0 0 0 0 | 13 Jihad_Mohammed_Ali_(Azzam) | 0 0 0 0 0 0 | 15 Abdullah_Ahmed_Abdullah_(Saleh) | 1 3 0 0 1 5 | 16 Abdal_Rahman | 0 0 0 0 0 0 | --------------------------------------------------------------

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E-I Index

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E-I Index