Rasa: 2.3.4 Release

Bugfixes

• #8014: Setting model_confidence=cosine in DIETClassifier, ResponseSelector and TEDPolicy is deprecated and will no longer be available. This was introduced in Rasa Open Source version 2.3.0 but post-release experiments suggest that using cosine similarity as model's confidences can change the ranking of predicted labels which is wrong.

model_confidence=inner is deprecated and is replaced by model_confidence=linear_norm as the former produced an unbounded range of confidences which broke the logic of assistants in various other places.

We encourage you to try model_confidence=linear_norm which will produce a linearly normalized version of dot product similarities with each value in the range [0,1]. This can be done with the following config: yaml - name: DIETClassifier model_confidence: linear_norm constrain_similarities: True This should ease up [tuning fallback thresholds](./fallback-handoff.mdx#fallbacks) as confidences for wrong predictions are better distributed across the range [0, 1].

If you trained a model with model_confidence=cosine or model_confidence=inner setting using previous versions of Rasa Open Source, please re-train by either removing the model_confidence option from the configuration or setting it to linear_norm.

model_confidence=cosine is removed from the configuration generated by [auto-configuration](model-configuration.mdx#suggested-config).