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name: scienceclaw-benchmark-for39 description: "Use when a task asks to predict whether students answer held-out diagnostic multiple-choice questions correctly, from a large student-by-question correctness matrix and a small per-student budget of adaptively chosen revealed answers (about 10), delivered as a 0/1 prediction per target cell and judged by accuracy; Eedi / NeurIPS 2020 Education Challenge Task 4 adaptive testing with item response theory (FoR39 of the companion ScienceClaw-Eval benchmark)." metadata: { "openclaw": { "emoji": "📊" } }

Adaptive testing and student answer prediction

Task

• Input: a training matrix answers (n_train, Q) (1 correct, 0 incorrect, -1 not answered; optional question subjects and student metadata); for the students to predict, can_query (n, Q) bool (cells that may be revealed) and targets (n, Q) bool (cells to predict). A querying tool declared by the task reveals a student's answers to chosen question ids, up to a per-student budget (10 in the companion benchmark).
• Deliverable: int array (n, Q) with 0 or 1 on every target cell and -1 elsewhere.
• Quality: accuracy over all target answers (the organiser averages over 10 query/target masks), higher is better. Reference: predict each question's most common training correctness.

Routes

• Two-parameter IRT with scilib.adaptive: fit_item_curves(answers) (marginal-likelihood EM, seconds for thousands of students), ability_posterior, predict_proba(model, revealed), select_queries(model, can_query, revealed, k, budget, method="batch"|"bald"), predict(model, revealed, targets), merge_revealed. model may be the training matrix itself (the fit is cached per process). Typed operators: irt_item_response_fit, irt_adaptive_question_selection, irt_correctness_prediction.
• Pattern: split the budget into a few rounds. Round 1 select_queries(answers, can_query, [], k1); query; round 2 select_queries(answers, can_query, [rev1], k2); query; finally predict(answers, [rev1, rev2], targets). Selection is deterministic and the list for k is a prefix of the list for a larger k.
• Before spending real queries, simulate the procedure on held-out training students (hide a random 20 percent of their answered cells as targets, query from the rest) to compare random, BALD and batch selection with the majority reference.

Pitfalls

• Treat the budget as counting distinct revealed cells over the whole solve, including exploratory or later-discarded calls. Fix the number and size of rounds before querying: changing k or the round plan changes the cells later rounds ask for and can exceed the budget.
• Only answered, non-target questions are queryable; never try to read target answers or labels of the students being predicted, and fit item curves on the training matrix only.
• Each query call returns the revealed array for its own cells only (-1 not revealed, 0 incorrect, 1 correct). Keep every array and pass the list; do not pass revealed_values (chosen option 1-4), which is a different encoding.
• Per-student evidence is only about 10 answers, so accuracy gains over the majority reference are modest and noisy on a few dozen students; report the gain together with its sample size.