{"model":"channel_choice_v1","approach":"s_learner (pooled repurchase v4 + epd v2 with source feature varied)","use_case":"Pre-funding GSE channel routing: predicts the expected-loss differential of delivering the same loan to Fannie Mae (FNM_SFP) vs Freddie Mac (FRE).","underlying_models":{"repurchase":{"model_version":"repurchase_v3.0.0","vintages_trained_on":["2020","2021","2022","2023"],"test_auc":0.8110518679364755},"epd":{"model_version":"epd_v1.0.0","vintages_trained_on":["2020","2021","2022","2023"],"test_auc":0.8216526919477698}},"loss_assumptions":{"loss_per_repurchase_usd":200000.0,"loss_per_epd_usd":10000.0,"immaterial_differential_usd":20.0,"note":"Defaults; override per-request via loss_per_repurchase_usd / loss_per_epd_usd fields on the payload."},"expected_inputs":{"numeric":["borrower_fico","co_borrower_fico","original_ltv","original_cltv","dti","mi_percent","original_upb","original_interest_rate","original_loan_term_months","number_of_units","number_of_borrowers","max_dq_status_1_6","dq_months_1_6","ever_60dq_1_6","ever_90dq_1_6","ever_modified_1_6","upb_decline_pct_1_6","obs_months_1_6"],"categorical":["source","loan_purpose","channel","property_type","occupancy","first_time_homebuyer","product_type","property_valuation_method","origination_year","origination_month","property_state","seller_name"]},"output_fields":["fannie.{repurchase_probability, epd_probability, expected_repurchase_loss_usd, expected_epd_loss_usd, expected_total_loss_usd}","freddie.{...same...}","expected_loss_differential_usd (positive = Freddie is cheaper)","recommended_channel (FNM_SFP / FRE / EITHER)","rationale"]}