Analysing the map

Once you have a map, you may want to examine it for themes and patterns. This is easiest if you examine portions of the map, or 'sub-maps', one at a time. As Barbrook-Johnson and Penn (2021) explain, network analysis can be combined with subjective information to answer a range of questions, as indicated in the table below.

Way to start Starting point options How to build Interpretation How to do it with PRSM
Stakeholder-suggested factors Intervention or controllable factors Downstream factors and edges What is the intervention or controllable factor affecting? Unexpected indirect effects? Select the intervention factor and choose ‘Show only Factors downstream’
For multiple factors create a union or intersection of multiple downstream submaps How are multiple interventions complementing or clashing with each other? Select all the interventions and choose ‘Show only Factors downstream’
Paths between intervention factors and outcome factors, including ego networks of factors on paths What does the intervention rely on to achieve its goals? What wider context might affect it? Select all the factors on the path(s) between the intervention(s) and the outcomes(s), and choose ‘Show only Factors 1 link away’ (or 2 or 3 links away)
Important or outcome factors Upstream factors and edges What is influencing the thing we care about? Constraints? Control? Buffered or buffeted? Select the intervention factor and choose ‘Show only Factors upstream’
For multiple factors create a union or intersection of ego networks. Or, pull out paths between outcomes. What trade-offs or synergies might there be between achieving the things we care about? Select all the interventions and choose ‘Show only Factors upstream’

Ego networks

 

What is influencing the thing we care about, what does it influence and how do those things interact? Select the factor and choose ‘Show only Factors 1 link away’ (or 2 or 3 links away)
Union or intersection of upstream factors and edges What factors influence multiple outcomes? Identify potential levers in the system, co-benefits, synergies, or risks. Select all the outcome factors and choose ‘Show only Factors upstream’
Vulnerable to change factors Up and/or downstream factors and edges What might mitigate change in this factor? What impact might change have? Select one or more factors and choose ‘Show only Factors 1 link away’ (or 2 or 3 links away)
Union/intersection multiple downstream sub maps Are there compound risks, how might interventions interact with external change? Select factors and choose ‘Show only Factors downstream’
System-suggested factors Influential (i.e. many outgoing connections) Downstream factors and edges What is this influential thing affecting? Vulnerability or lever? First, set ‘Size Factors to: Outputs’ to see which factors have many outgoing connections. Then select an influential factor and choose ‘Show only Factors downstream’.
Central to the map (i.e. well-connected, or bridging) Downstream and/or upstream factors and edges What is influencing this central factor? What influence does it have? Bottleneck, bridge, transmitter? First, set ‘Size Factors to: Centrality’ to see which factors are central. Then select a central factor and choose ‘Show only Factors upstream’.
Ego networks What does this factor bridge or connect? First, set ‘Size Factors to: Centrality’ to see which factors are central. Then select a central factor and choose ‘Show only Factors 1 link away’.
Influenced (i.e. many incoming connections) Upstream factors and edges What is influencing this highly influenced factor? Buffered or buffeted? First, set ‘Size Factors to: Inputs’ to see which factors have many incoming connections. Then select a factor and choose ‘Show only Factors upstream'.
Unusual network property Any of the above Does this factor play an important but counter-intuitive role in the system?  Set ‘Size Factors to: Leverage’ to see which factors have either many incoming but few outgoing connections or few outgoing but many incoming connections.

With thanks to Alex Penn and Pete Barbrook-Johnson for the original of this table, adapted from

Barbrook-Johnson, P., & Penn, A. (2021). Participatory systems mapping for complex energy policy evaluation. Evaluation, 27(1), 57–79.