PDAG cseparation

[kenneth-lee-ch]

I am trying the Cseparation in PDAG object, would you please explain why I would the following error? Is it because I specified the NodeSet incorrectly?

import pyAgrum as gum
p = gum.PDAG()
p.addNodes(10)
p.addArc(0,1)
p.addArc(1,2)
p.cSeparation(set([0]), set([2]), set([1]))

[kenneth-lee-ch]

I tried both function Dseparation and Cseparation as follows based on my guess that they both take the same arguments. The one with d-separation went through, but not for c-separation.

[phwuil]

You are right, thanks ! PDAG.cSeparation was not properly wrapped. It will be in the next release !

[kenneth-lee-ch]

@phwuil Thanks for looking into this. Should I just install pyagrum-nightly to get the latest version?

[phwuil]

Tag 1.8.0 is close. :-)

So tomorrow (in more than 12 hours), you should have either 1.8.0 or 1.7.1.9-nigthly that contains this commit.

[kenneth-lee-ch]

@phwuil I tried the following. Would you mind explaining why the output is true while having an edge between 0 and 1? Is there a way to check for separation for each DAG that is represented by the PDAG assuming two directions "->" and "<-" are encoded in every undirected edge ?

import pyAgrum as gum

p = gum.PDAG()
p.addNodes(10)
p.addEdge(0,1)
p.cSeparation([0], [1], [2])

[phwuil]

Hi @kenneth-lee-ch , believe it or not, we did not try cSeparation on such simple graphs and indeed there was a bug. It's a bit awkward.
It is fixed and should be in nightly in less than 12 hours.

[kenneth-lee-ch]

Thanks @phwuil. I updated with the latest version but I've found the following, how is 2 separated from 3?

import pyAgrum as gum

p = gum.PDAG()
p.addNodes(4)
p.addEdge(0,1)
p.addArc(1,2)
p.addArc(3,2)
p.cSeparation(2, 3, [])

One more example below, how can you possibly conclude 0 is separated from 2 in this case if I have an edge between 0 and 1? I thought it should be applying d-separation in every possible DAG representation from the PDAG that has no cycles.

import pyAgrum as gum

p = gum.PDAG()
p.addNodes(4)
p.addEdge(0,1)
p.addArc(1,2)
p.addArc(3,2)
p.cSeparation(0, 2, [])

[phwuil]

We definitely didn't do the right test suite for PDAG::cSeparation (there are about 30 tests for PDAG though ...) :-(

Thanks for taking the role of beta-testers!
(fixed in the next nightly)

[phwuil]

Bugfixes are included in 1.8.1