Change VertexSize in a big graph

Question

I am trying to understand when VertexSize property works on the graph. I experimented with a small number of nodes (about 100) and try to change the size of only 5 vertices out of 100 and it worked. However, when you take a graph with a large number of nodes (for example 1000 nodes and 2000 edges - RandomGraph[{1000,2000}] and try to change the size of 10 vertices, VertexSize does not seem to work. I even tried with affixing the property to the vertex by using Property but could not get to work.

So, after how many nodes does VertexSize does not work? Is there a way to get around this?

Answer 1

The following work in version 9:

RandomGraph[{1000, 2000}, 
 VertexSize -> Join[{_ -> Scaled[.01]}, Thread[Range[10] -> Scaled[.04]]]]

RandomGraph[{1000, 2000}, 
 VertexSize -> Join[{_ -> 3}, Thread[Range[10] -> 10]]]

Update: For versions 11+ , as shown in halmir's answer, explicit setting of GraphStyle or VertexShapeFunction options gives the desired result. In particular, using the option GraphStyle with any value, e.g.

GraphStyle -> {}
GraphStyle- > "BasicBlue"
GraphStyle-> blah

with the same VertexSize settings as in the examples above gives

Answer 2

You could specify VertexShapeFunction or set GraphStyle -> "Default"

RandomGraph[{1000, 2000}, VertexSize -> 6, VertexShapeFunction -> "Circle"]

RandomGraph[{1000, 2000}, VertexSize -> 5, GraphStyle -> "Default" ]