Introduction
Using data from dogesr (Merelo-Guervós 2022), we will, in this
vignette, analyze the change of the social network before and after the
Serrata (Puga and Trefler 2014),
revealed as a watershed event in the analysis performed in (Merelo 2023)
Set up
The main events that led to the Serrata happened during the
government of the doge Pietro Gradenigo. Let’s check the effect of that
event in the social netWe will then create two networks, one including
that doge, the next one with all the others
library(dogesr)
library(igraph)
pre.serrata <- marriage.graph.slice(to="Pietro Gradenigo")
post.serrata <- marriage.graph.slice(from="Marino Zorzi")
Social networks pre and post-Serrata
This will call the function that creates, from raw data, the
igraph data structure with which we can work. We still need
to simplify them to be able to work with it.
weightify <- function( a.graph ) {
other.graph <- a.graph
E(other.graph)$weight <- 1
other.graph <- simplify(other.graph, edge.attr.comb=list(weight="sum"))
return(other.graph)
}
pre.serrata <- weightify(pre.serrata)
post.serrata <- weightify(post.serrata)
V(pre.serrata)$EV <- unname(unlist(eigen_centrality(pre.serrata)$vector))
V(post.serrata)$EV <- unname(unlist(eigen_centrality(post.serrata)$vector))
plot(pre.serrata,vertex.size=V(pre.serrata)$EV, layout=layout_nicely, vertex.label.cex=0.7)
plot(post.serrata,vertex.size=V(post.serrata)$EV, layout=layout_nicely, vertex.label.cex=0.7)
The pre-Serrata graph is on the top, the post-serrata on the bottom.
Before the Serrata, there were small (up to 4-5) sets of connected
components, the biggest one the “star” around the Tiepolo family (which
was an important part of the early XIV century rebellion); however, the
Serrata had the effect of connecting the network, mainly because there
were many more doges per generation (as explained in (Merelo 2023)), but also because marrying became
an tactical move to increase the reach of the social network.
It should be noted, however, that doges’ marriages were but a small
part of the complete Venetian social network; however, it is an
important sample that, besides, shows who arrived to the summit of power
(or servitude to the state, depending on how you look at it).
Social networks pre and post-Serrata
This will call the function that creates, from raw data, the
igraphdata structure with which we can work. We still need to simplify them to be able to work with it.The pre-Serrata graph is on the top, the post-serrata on the bottom. Before the Serrata, there were small (up to 4-5) sets of connected components, the biggest one the “star” around the Tiepolo family (which was an important part of the early XIV century rebellion); however, the Serrata had the effect of connecting the network, mainly because there were many more doges per generation (as explained in (Merelo 2023)), but also because marrying became an tactical move to increase the reach of the social network.
It should be noted, however, that doges’ marriages were but a small part of the complete Venetian social network; however, it is an important sample that, besides, shows who arrived to the summit of power (or servitude to the state, depending on how you look at it).