[igraph] Question about degree.distribution

[Narges Zarabi]

Hi,

I have directed network (attached file), and I use igraph in R to plot the cumulative degree distribution for total/in/out degrees (the plot is in log-log scale). What I don't understand is, why the total degree distribution is not changing (lets say for degrees around 100), while both in and out degree distributions are decreasing? Shouldn't the "in" and "out"degree  distribution sum up to the total degree distribution? is there any normalization function causing this? I would really appreciate any help to understand the graph. Many thanks

g <- read.graph("network.txt" , format ="edgelist", directed = T)

dd<-degree.distribution(g, mode="total", cumulative =T)

plot(dd, log="xy", xlab="degree", ylab="cumulative frequency", main = "degree distribution (total/in/out)")

ddin <- degree.distribution(g, mode="in",cumulative = T)

points(ddin,col=2, pch=2)

ddout <- degree.distribution(g, mode="out",cumulative = T)

points(ddout, col=3, pch=3)

legend(1, 0.2, c("total degree","in degree","out degree"), col=1:3, pch=1:3, ncol=1, yjust=0, lty=0)

Regards,

Narcis

network.txt
Description: Text document