| metric | value |
|---|---|
| area under ROC curve | 0.76 |
| area under precision-recall curve | 0.12 |
| accuracy | 0.52 |
| precision | 0.05 |
| recall | 0.83 |
| f1 score | 0.10 |
| mean log loss | 0.95 |
| gini coefficient | 0.51 |
| brier skill score | 0.04 |
enrolled in chip
Built from the latest training run on 2026-09-30 17:45 UTC, not from a released model set. The released documentation is at https://matter.indigo.engineering/docs/.
Overview
This model predicts enrollment in the Children’s Health Insurance Program (CHIP), which provides coverage to children in families that earn too much to qualify for Medicaid but cannot afford private insurance.
Trained on survey data, it uses household composition signals, economic indicators, and neighborhood demographics to identify likely CHIP households.
Organizations can use these scores for outreach around children’s health coverage and family benefits access.
- approach: boosted tree classifier
- training rows: 16,076
- last updated: 2026-09-02 16:37:30
Validation
Lift Chart

Each bar shows how much more common the outcome is within a score decile than in the population overall. Bars taller than the dashed line (lift of 1) mean the model’s top-ranked groups concentrate the outcome; a steady decline from decile 1 to 10 indicates the model is ranking effectively.
Calibration Plot

Bars of similar height within each decile indicate well-calibrated predictions. Systematic differences reveal where the model over- or under-predicts.
Cumulative Gains

The further the model curve bows above the diagonal, the better the model concentrates the outcome in its top-ranked predictions.
Decile Analysis Table
| decile | count | mean actual | mean predicted | mae | lift |
|---|---|---|---|---|---|
| 10 | 399 | 0.11 | 0.11 | 0.004 | 3.38 |
| 9 | 398 | 0.07 | 0.04 | 0.02 | 2.00 |
| 8 | 398 | 0.05 | 0.03 | 0.02 | 1.39 |
| 7 | 398 | 0.03 | 0.02 | 0.004 | 0.85 |
| 6 | 399 | 0.02 | 0.02 | 0.0008 | 0.69 |
| 5 | 398 | 0.02 | 0.02 | 0.003 | 0.54 |
| 4 | 398 | 0.01 | 0.02 | 0.007 | 0.38 |
| 3 | 398 | 0.02 | 0.02 | 0.004 | 0.46 |
| 2 | 398 | 0.002 | 0.02 | 0.02 | 0.08 |
| 1 | 399 | 0.008 | 0.02 | 0.009 | 0.23 |
Architecture
This model is a boosted-tree classifier trained with BigQuery ML.
Hyperparameter configuration
- max iterations: 20
- learn rate: 0.1813
- l1 regularization: 1.497e-09
- l2 regularization: 4.699
- min relative progress: 0.01
- early stop: TRUE
- input label columns: benefits_enrolled_in_chip
- data split method: AUTO_SPLIT
- max tree depth: 3
- subsample: 1
- min split loss: 0
- num trials: 12
- max parallel trials: 4
- hparam tuning objectives: ROC_AUC
- enable global explain: TRUE
- category encoding method: LABEL_ENCODING
- booster type: GBTREE
- num parallel tree: 1
- tree method: AUTO
- min tree child weight: 1
- instance weight column: sample_weight
- xgboost version: 0.9
- auto class weights: FALSE
Features
Importance

Interaction terms are split evenly between the features they combine.
Sourcing
Revelio Labs
- current position salary
State voter files (via TargetSmart)
- age
- registered democrat
- registered republican
TargetSmart
- abortion issue motivation score
- child tax credit support score
- children present score
- college graduate score
- double negative gop score
- harris support score
- income rank
- midterm general turnout score
- paid leave support score
- partisan score
- progressive tax support score
- race: aapi
- race: black
- race: white
- working class score
U.S. Census American Community Survey
- block group % aapi
- block group % some college
Verisk (via TargetSmart)
- mobile home
- net worth
- residence tenure
- residence year built
Implementation
Prediction distribution

| statistic | value |
|---|---|
| mean | 0.06 |
| std dev | 0.07 |
| min | 0.02 |
| 25th | 0.02 |
| median | 0.03 |
| 75th | 0.09 |
| max | 1 |
Segments
| segment | lowest score | highest score | share of records |
|---|---|---|---|
| Most likely | 0.17 | 1 | 5.7% |
| Somewhat likely | 0.14 | 0.16 | 5.7% |
| Least likely | 0.02 | 0.13 | 88.6% |
External validity
Our model indicates that 6% of people with scored records have a child enrolled in CHIP. CMS Medicaid/CHIP Enrollment and Census ACS 2023 place household CHIP enrollment at roughly 2–3% of U.S. adults.