| metric | value |
|---|---|
| area under ROC curve | 0.76 |
| area under precision-recall curve | 0.15 |
| accuracy | 0.55 |
| precision | 0.11 |
| recall | 0.88 |
| f1 score | 0.20 |
| mean log loss | 0.91 |
| gini coefficient | 0.53 |
| brier skill score | 0.03 |
uninsured
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 whether a voter is currently uninsured — the policy-relevant minority in need of enrollment assistance and coverage-access outreach.
Trained on survey data, it uses age, employment, income, and area-level coverage indicators to identify voters without any current health insurance.
Organizations can use these scores to target enrollment-assistance campaigns, Medicaid and ACA marketplace outreach, and coverage-gap advocacy.
- approach: boosted tree classifier
- training rows: 17,117
- last updated: 2026-09-06 19:39:03
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 | 432 | 0.18 | 0.20 | 0.03 | 2.84 |
| 9 | 431 | 0.14 | 0.10 | 0.04 | 2.21 |
| 8 | 431 | 0.09 | 0.07 | 0.02 | 1.48 |
| 7 | 431 | 0.08 | 0.06 | 0.02 | 1.22 |
| 6 | 431 | 0.06 | 0.05 | 0.01 | 1.03 |
| 5 | 431 | 0.03 | 0.04 | 0.005 | 0.52 |
| 4 | 431 | 0.009 | 0.03 | 0.02 | 0.15 |
| 3 | 431 | 0.01 | 0.03 | 0.01 | 0.22 |
| 2 | 431 | 0.02 | 0.02 | 0.007 | 0.26 |
| 1 | 431 | 0.005 | 0.02 | 0.02 | 0.07 |
Architecture
This model is a boosted-tree classifier trained with BigQuery ML.
Hyperparameter configuration
- max iterations: 20
- learn rate: 0.2282
- l1 regularization: 0
- l2 regularization: 4.904e-11
- min relative progress: 0.01
- early stop: TRUE
- input label columns: health_uninsured
- data split method: AUTO_SPLIT
- max tree depth: 4
- subsample: 0.6395
- 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
Agency for Healthcare Research and Quality
- tract % direct-purchase insurance only
- tract unemployment rate
CDC PLACES
- tract % adults 18-64 uninsured
Federal Reserve
- county debt-to-income decile
Georgetown University Center for Children and Families
- county medicaid / chip coverage rate
Revelio Labs
- avg salary differential
- current position salary
- current position tenure (days)
- min salary
- number of jobs held
State voter files (via TargetSmart)
- age
- years registered to vote
TargetSmart
- campaign finance reform score
- catholic score
- high school only score
- marriage score
- midterm general turnout score
- non-presidential primary turnout score
- off-year general turnout score
- path to citizenship support score
- race: white
U.S. Census American Community Survey
- block group % age 50–64
- block group % high school diploma
Verisk (via TargetSmart)
- clerical occupation
- newspaper reader
Implementation
Prediction distribution

| statistic | value |
|---|---|
| mean | 0.09 |
| std dev | 0.07 |
| min | 0.01 |
| 25th | 0.04 |
| median | 0.07 |
| 75th | 0.11 |
| max | 0.80 |
Segments
| segment | lowest score | highest score | share of records |
|---|---|---|---|
| Most likely | 0.18 | 0.80 | 9.3% |
| Somewhat likely | 0.13 | 0.17 | 9.1% |
| Least likely | 0.01 | 0.12 | 81.5% |
External validity
Our model indicates that 9% of people with scored records are currently uninsured. As of 2024, ~23.5M U.S. adults were uninsured — roughly 9% of the U.S. adult population (2024 NCHS National Health Interview Survey).