I have a dataframe of paper IDs and author names like so:
library(tidyverse)
df <- tribble(
~id, ~name,
1, "a",
1, "b",
2, "b",
2, "c",
3, "b",
3, "c"
)
The interpretation is that authors a and b wrote paper 1 together, while authors b and c wrote papers 2 and 3 together.
I would like to plot this using e.g. ggraph like so:
a - b = c
That is, I would like to to have authors as nodes and number of papers co-authored as edge weights.
You can define the adjacency matrix with base R. Try this:
# create a 2-mode sociomatrix
mat <- t(table(df))
# create adjacency matrix as product of the 2-mode sociomatrix
adj.mat <- mat %*% t(mat)
# if you want the diagonal to be 0 use : diag(adj.mat) <- 0. This can also be done directly
# with igraph
# define your network
library(igraph)
net <- graph_from_adjacency_matrix(adj.mat, mode = "undirected", weighted = TRUE,
diag = FALSE)
V(net)$name # vertices (nodes) name
E(net) # edges
E(net)$weight # edges weight
# example of plot
library(ggraph)
ggraph(net, layout = "igraph", algorithm = "kk") +
geom_edge_link(aes(width = weight)) +
geom_node_point(size = 8, colour = "steelblue") +
geom_node_text(aes(label = name)) +
ggforce::theme_no_axes()
# output
