Misc. fixes for Pytorch QA examples: (#16958)

1. Fixes evaluation errors popping up when you train/eval on squad v2 (one was newly encountered and one that was previously reported Running SQuAD 1.0 sample command raises IndexError #15401 but not completely fixed).
2. Removes boolean arguments that don't use store_true. Please, don't use these: *ANY non-empty string is being converted to True in this case and this clearly is not the desired behavior (and it creates a LOT of confusion).
3. All no-trainer test scripts are now saving metric values in the same way (with the right prefix eval_), which is consistent with the trainer-based versions.
4. Adds forgotten model.eval() in the no-trainer versions. This improved some results, but not everything (see the discussion in the end). Please, see the F1 scores and the discussion below.
This commit is contained in:
Leonid Boytsov
2022-04-27 12:51:39 +00:00
committed by GitHub
parent 49d5bcb0f3
commit c82e017aa9
6 changed files with 105 additions and 16 deletions

View File

@@ -158,7 +158,7 @@ def postprocess_qa_predictions(
"end_logit": end_logits[end_index],
}
)
if version_2_with_negative:
if version_2_with_negative and min_null_prediction is not None:
# Add the minimum null prediction
prelim_predictions.append(min_null_prediction)
null_score = min_null_prediction["score"]
@@ -167,7 +167,11 @@ def postprocess_qa_predictions(
predictions = sorted(prelim_predictions, key=lambda x: x["score"], reverse=True)[:n_best_size]
# Add back the minimum null prediction if it was removed because of its low score.
if version_2_with_negative and not any(p["offsets"] == (0, 0) for p in predictions):
if (
version_2_with_negative
and min_null_prediction is not None
and not any(p["offsets"] == (0, 0) for p in predictions)
):
predictions.append(min_null_prediction)
# Use the offsets to gather the answer text in the original context.
@@ -350,9 +354,12 @@ def postprocess_qa_predictions_with_beam_search(
start_index >= len(offset_mapping)
or end_index >= len(offset_mapping)
or offset_mapping[start_index] is None
or len(offset_mapping[start_index]) < 2
or offset_mapping[end_index] is None
or len(offset_mapping[end_index]) < 2
):
continue
# Don't consider answers with a length negative or > max_answer_length.
if end_index < start_index or end_index - start_index + 1 > max_answer_length:
continue
@@ -381,7 +388,9 @@ def postprocess_qa_predictions_with_beam_search(
# In the very rare edge case we have not a single non-null prediction, we create a fake prediction to avoid
# failure.
if len(predictions) == 0:
predictions.insert(0, {"text": "", "start_logit": -1e-6, "end_logit": -1e-6, "score": -2e-6})
# Without predictions min_null_score is going to be None and None will cause an exception later
min_null_score = -2e-6
predictions.insert(0, {"text": "", "start_logit": -1e-6, "end_logit": -1e-6, "score": min_null_score})
# Compute the softmax of all scores (we do it with numpy to stay independent from torch/tf in this file, using
# the LogSumExp trick).