Network density and coalition development

In an article on youth violence prevention coalitions, Bess (2015) investigated the ways that the coalition impacted the broader youth violence prevention (YVP) system.  The researcher analyzed three different network properties: density, hierarchy/centralization, and homophily.  For the sake of clarity, I will be discussing how the network density aspects of the study related to coalition capacity building.

As Figure 1 shows, Bess (2015) conceptualized the broad YVP Intervention System (Network A) as being comprised of two subsystems (Networks B and C).  The official YVP coalition members made up Network B and the other organizations that worked on YVP issues but were not official members comprised Network C.

Research question and hypotheses

How does the density of the YVP Intervention System network change over the five year time period?  In this study, density represents collaboration, with higher levels of network density corresponding to higher levels of collaboration.  Previous research on coalition building has shown that collaboration increases as the coalition forms, and then decreases as the coalition stabilizes and moves into implementation.  Based on that research, Bess (2015) hypothesized that network density would increase during beginning years of the study (coalition formation) and then would decline.

Sample population

The sample included 99 organizations (both public and private non-profits) that participated in YVP work in a mid-sized southeastern city (Bess, 2015).  The sample varied from year to year as organizations came and went.  There were 99 today organizations that participated in at least one year of the study.

Data collection

Investigators collected the data through yearly in-person interviews with organization members who were most familiar with the group’s YVP work (Bess, 2015).  To construct the networks, researchers gave participants a list of the active YVP organizations and asked the participants to identify the organizations they had collaborated with on YVP activities.

Network Structure

The nodes in the networks were the YVP organizations (Bess, 2015).  Official coalition members made up Network B and YVP organizations that were not in the coalition comprised Network C.  Networks B and C combined to form Network A.  The network links were the collaborative relationships between nodes.  A link was formed when agency A listed agency B as an organization with which they collaborated.  The networks were directed because reciprocity was not assumed.

Results

Bess (2015) noted that density is often a function of network size, as larger networks tend to have lower density.  Because the network size varied over the course of the study, analysis focused on overall patterns in increases and decreases instead of discrete values.  As hypothesized, network density increased in the initial years of all three networks and then declined in the later years. Specifically, density peaked in year two and then declined to similar or lower levels as the baseline year.  

These results supported components of coalition development theory (Bess, 2015).  Coalition development theory states that collaboration is highest when coalitions are forming, and then decreases once the coalition has built the necessary capacity for work.  In this context, lower levels of collaboration represent coalition efficiency, not dissolution.  

Network density measures are critical for this type of analysis because they present a picture of of the overall functioning of the network as opposed to information on the nodal level.

Reference

Bess, K. D. (2015). Reframing coalitions as systems interventions: A network study exploring the contribution of a youth violence prevention coalition to broader system capacity. American Journal of Community Psychology, 55, 381-395. doi: 10.1007/s10464-015-9715-1