The DAG is not a DAG!

[samanemami]

Subject of the issue

I tried to estimate the DAG structure with a tree search but I have repeated nodes with various connections!

Your environment

• pgmpy version: 0.1.19
• Python version: 3.6.5, 3.9, 3.10.0
• Operating System: Windows and Linux

Steps to reproduce

est = TreeSearch(values, root_node='B')
model = est.estimate(estimator_type='chow-liu')

Expected behaviour

The edges should be unique and directed not multiple

Actual behaviour

Having duplicated nodes with various edges

[ankurankan]

@samanemami Thanks for creating the issue. Would it be possible for you to share some of your data or give more details on what it looks like? I am not able to reproduce your issue using a different dataset.

In [1]: from pgmpy.utils import get_example_model

In [2]: model = get_example_model('alarm')
d
In [3]: data = model.simulate()
Generating for node: BP: 100%|██████████████████████████████████████████| 37/37 [00:00<00:00, 600.00it/s]

In [4]: from pgmpy.estimators import TreeSearch

In [6]: est = TreeSearch(data, root_node='HISTORY')

In [7]: est.estimate(estimator_type='chow-liu')
Building tree: 100%|████████████████████████████████████████████████| 666/666.0 [00:00<00:00, 756.91it/s]
Out[7]: <pgmpy.base.DAG.DAG at 0x7f3456214850>

In [8]: dag = est.estimate(estimator_type='chow-liu')
Building tree: 100%|████████████████████████████████████████████████| 666/666.0 [00:00<00:00, 769.44it/s]

# Nodes are exactly the same as in data.
In [12]: set(list(dag.nodes())) == set(list(data.columns))
Out[12]: True

# There are no repeated edges.
In [15]: len(list(dag.edges())) == len(set(list(dag.edges())))
Out[15]: True

In [29]: dag.to_daft('circular', pgm_params={'grid_unit': 10})
Out[29]: <daft.PGM at 0x7f3446375a60>

# Network plot attached below
In [30]: _.render()

[samanemami]

Hi @ankurankan

Thank you for your kind reply and the shared experiment.
I reproduced everything from scratch and I found that the DAG had overwritten on the previous and caused the issue.

Thank you again for your amazing repository and support.