metalearner
Estimate conditional average treatment effects (CATE) using S-, T-, X-, R-, or DR-learners. Compare learner outputs to detect bias and validate causal assumptions for binary treatments.
Instructions
Meta-learner framework for CATE: S-, T-, X-, R-, DR-Learner. Validation: certified parity evidence. Assumptions: Unconfoundedness: Y(d) perp D | X; Overlap: 0 < P(D=1 | X) < 1; For R-Learner / DR-Learner: orthogonality between treatment residual and outcome residual. Pre-conditions: binary treatment (0/1); covariates numeric; categoricals encoded; enough treated AND control to train separate outcome models (T/X/DR-Learner). Failure modes: Large divergence across learner types -> Use sp.compare_metalearners to identify which learner is biased; DR-Learner is safest under model misspecification; S-Learner estimates near zero regardless of true effect -> S-Learner regularization smooths treatment coefficient toward zero; use T/X/DR instead; X-Learner fails when treated group is very small -> X-Learner needs well-identified control-outcome model; fall back to T-Learner or weighted T-Learner. Alternatives: sp.causal_forest, sp.dml, sp.tmle, sp.bcf. Typical minimum N: 500.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| y | Yes | Outcome variable column name or outcome array. | |
| treat | Yes | Binary treatment column (0/1) | |
| detail | No | Payload depth: 'minimal' (~150 tokens) for sub-step calls where only the point estimate is needed; 'standard' (~1K tokens) for diagnostics + coefficient table; 'agent' (~2K tokens, default) adds violations / next_steps / suggested_functions so the LLM can plan its next call without another round-trip. | agent |
| learner | No | Learner type | dr |
| as_handle | No | If true, cache the fitted result on the server and return result_id + result_uri alongside the JSON payload so a subsequent tools/call can chain without re-running. | |
| data_path | Yes | Absolute path or URL to a data file. Supported: .csv / .tsv / .txt (delimited), .parquet / .pq, .feather / .arrow, .xlsx / .xls, .dta (Stata), .json / .jsonl. Schemes: file://, s3://, gs://, https://. | |
| result_id | No | Optional handle to a previously-fitted result (returned by an earlier call when as_handle=true). Tools that operate on a fitted object accept this in place of re-supplying data_path + columns. | |
| covariates | Yes | Covariate matrix, DataFrame, or column names. | |
| data_columns | No | Optional column projection. Parquet/Feather/Stata loaders honour this for fast partial reads. | |
| data_sample_n | No | Optional uniform random subsample size (seed=0, deterministic) — useful on huge panels. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||