Pretrained Model Vignettes

Click Here for three vignettes on using Causal Forests for Causal Inference
Author

George I. Hagstrom

Published

May 11, 2026

Hello class,

I have uploaded a google colab notebook that goes through three fine-tuning examples related to your homework assignment. Your homework assignment is essentially to pick one of these examples, modify it according to the instructions, and then run it and observe the results. The examples involve both training/fine-tuning a network, and also exploring how to optimize hyperparameters using ‘optuna’. The three examples are:

  1. Using an LSTM to perform financial sentiment analysis using both trained and Bert embeddings
  2. Fine-tuning ModernBERT to do the same, exploring how to only fine-tune part of the network
  3. Fine-tuning an open-weight LLM called Qwen 2.5 using QLoRA. We also look at varying the perturbation rank and the parts of the network targeted.

Code is available here: Pretrained Vignette

Note that this is somewhat of a living document. At the moment some of the initial code is not “executed”. There will be videos depending on how much is covered in the class meetup today.