Determine in-degree for each node in a model

Calculate the in-degree of each node based on external transfer events ("extTrans") in the model's schedules events.

Usage

indegree(model)

Arguments

model

A SimInf_model object containing the event schedule.

Value

An integer vector where each element corresponds to a node, containing the count of unique source nodes sending individuals to it.

Details

The in-degree is defined as the number of unique source nodes that have sent individuals to the target node at least once. This metric measures the connectivity of the network, indicating how many different neighbors directly supply individuals to a specific node.

See also

outdegree for calculating the number of unique destination nodes a node sends individuals to. events_SIR for example event data used in network analysis. SimInf_events for details on the structure of scheduled events.

Examples

## Create an 'SIR' model with example data.
model <- SIR(
  u0 = u0_SIR(),
  tspan = 1:1460,
  events = events_SIR(),
  beta = 0.16,
  gamma = 0.077
)

## Calculate the in-degree for each node.
deg <- indegree(model)

## View the in-degree for the first 6 nodes.
head(deg)
#> [1] 64 63 62 61 64 57

## Plot the distribution of in-degrees across all nodes.  This
## shows how many source nodes typically send individuals to a given
## node.
hist(
  deg,
  main = "Distribution of In-Degree (Unique Sources)",
  xlab = "Number of Unique Source Nodes"
)