Item analysis

Question statistics

Attempts · 6Questions with data · 5

Question	n	Difficulty p	Discrimination r_pb	Verdict
What is the main role of the softmax operation in the Bahdanau attention mechanism? r_pb=-0.15 < 0.15 — does not separate strong from weak	6	0.83	-0.15	low discrimination
What is the main advantage of using Byte-Pair Encoding (BPE) for tokenization in Transformers?	6	0.50	0.78	OK
Why does the LSTM's cell state update help prevent vanishing gradients for long-term dependencies?	6	0.67	0.75	OK
Why does the Transformer decoder use a causal mask during training?	6	0.83	0.53	OK
Why is it essential to scale the dot products by 1/√d in the Transformer's self-attention?	6	0.50	0.41	OK

Rejection rule (from 5 attempts): a question is flagged when its difficulty p falls outside 0.30–0.85 (share answering correctly) or its point-biserial discrimination drops below 0.15 (correlation with the rest of the attempt score). Retiring and regenerating flagged questions runs offline: uv run python -m app.quality … --regenerate.