Add documentation for neural-net based methods to Methodology

[ppstacy]

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#413 add documentation for neural-net based methods.

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[jeongyoonlee]

Hi — noting the current status of neural-net method documentation:

• DragonNet (causalml.inference.tf.dragonnet): Has docstrings and an example notebook at examples/dragonnet_example.ipynb.
• CEVAE (causalml.inference.torch.cevae): Has docstrings and an example notebook at examples/cevae_example.ipynb.

The main gap is that the Methodology section of the docs site doesn't cover these methods — the math and intuition are only in the docstrings and example notebooks.

If anyone would like to contribute a methodology writeup for DragonNet or CEVAE (similar to the existing sections for meta-learners and uplift trees), PRs are welcome. The docs source is in docs/.

[jbbqqf]

Hi! Triaging older issues — this one can probably be closed.

The neural-net methods now have docstrings + example notebooks in tree:

• DragonNet: causalml/inference/tf/dragonnet.py + examples/dragonnet_example.ipynb
• CEVAE: causalml/inference/torch/cevae/ + examples/cevae_example.ipynb

The Methodology page on Read the Docs (https://causalml.readthedocs.io/en/latest/methodology.html) lists the relevant references; if a specific NN-method paragraph is still missing there, a small follow-up doc PR would be the cleanest next step. Otherwise this one looks like it can be closed.

(Disclosure: I drafted this comment with help from Claude Code while triaging stale issues; the references above were verified manually against the current master branch.)