| name | pra-dsm |
| description | Quantify structural coupling between project tasks through shared resources and risks using the PRA package's Design Structure Matrices. Use when a user provides a resource–task matrix (and optionally a risk–resource matrix) and wants to see which task pairs are coupled and therefore tend to fail together.
|
When to use
The user has a binary matrix mapping resources to tasks (and optionally risks to
resources) and wants to identify coupled task pairs — the structural pathways
through which disruptions and risks propagate.
MCP tools
parent_dsm_tool(matrix_json) — the Parent DSM, derived from the
resource–task matrix S (rows = resources, columns = tasks) as
P = Sᵀ S. Off-diagonal P[j,k] counts resources shared between tasks j and
k. matrix_json is a JSON 2-D array, e.g.
[[1,0,1,0],[0,1,0,1],[1,0,1,1]].
grandparent_dsm_tool(s_matrix_json, r_matrix_json) — the Grandparent
DSM, which adds a risk layer via the risk–resource matrix R. Off-diagonal
G[j,k] counts risks shared between tasks j and k through the resource chain.
s_matrix_json: resource–task matrix S (resources × tasks).
r_matrix_json: risk–resource matrix R (risks × resources).
Interpreting results
Task pairs with high off-diagonal values are strongly coupled: in the Parent DSM
through shared resources, in the Grandparent DSM through shared risk exposure.
These pairs are prime candidates for contingency buffering or resource
decoupling, and pair naturally with a Monte Carlo correlation structure
(pra-monte-carlo).
Related (R-only)
For distribution-level propagation along the causal chain from risks to total
project cost, the package also provides probabilistic networks (prob_net,
prob_net_sim, prob_net_learn, prob_net_update). These are available from
an R session but are not exposed as MCP tools.
References
- Steward (1981), Systems Analysis and Management.
- Browning (2001), Applying the DSM to System Decomposition and Integration.
- Govan and Damnjanovic (2016, 2020), resource-based / structural-network
measures for project risk.