reports/shap_summary.json

What the model uses, not why someone left.

shap.TreeExplainer on the gradient-boosting classifier inside the saved pipeline. Output units: decision_function log-odds of P(Churn=Yes). On 1761 held-out rows the values plus the base value -1.556380 rebuild decision_function with max absolute error 0.000000.

Turn a local contribution off in the demo. The figures below stay on the published values.

Global

one-hot and scaled columns seen by the booster. 46 encoded columns. Mean absolute SHAP of an original field is the sum of the mean absolute SHAP of its encoded columns.

Largest mean absolute SHAP among encoded columns.
Encoded column	Mean absolute SHAP
cat__Contract_Month-to-month	0.643924
num__tenure	0.355529
cat__OnlineSecurity_No	0.241598

Original fields. The scale of the ink bars is the largest value in this table, Contract at 0.837003.
Original field	Mean absolute SHAP	Value
Contract		0.837003
tenure		0.355529
OnlineSecurity		0.241598
TechSupport		0.212835
MonthlyCharges		0.204335
InternetService		0.201518
TotalCharges		0.155191
PaymentMethod		0.141521
SeniorCitizen		0.044300
gender		0.019143

gender and SeniorCitizen are listed after the eight largest original fields so their mean absolute SHAP can be read on the same scale. They are not a second measurement.

Mean absolute SHAP by encoded column. The longest bar is cat__Contract_Month-to-month. — Mean absolute SHAP by encoded column.reports/shap/global_bar.png

Held-out TreeSHAP summary in the encoded column space the booster sees. — Held-out TreeSHAP summary.reports/shap/global_summary.png

Three held-out customers

Signed SHAP values summed within each original field. The plot label is field=raw value. The plotted bar is not a causal effect.

5343-SGUBI

P(Churn=Yes) 0.122990. Historical Churn No. Decision function -1.964413. SHAP base value -1.556380. SHAP sum -0.408033.

Contract = One year-0.511087
OnlineSecurity = No0.332220
tenure = 52-0.288727
TechSupport = No0.191892
PaymentMethod = Mailed check-0.145604

Positive SHAP raises the model's log-odds of churn.Negative SHAP lowers them. The bar is not a cause.

Local TreeSHAP plot for customer 5343-SGUBI. Signed values are summed back to original fields. — Local plot for 5343-SGUBI. The plotted bar is not a causal effect.reports/shap/local_5343-SGUBI.png

Local TreeSHAP plot for 5343-SGUBI — 5343-SGUBI · P(Churn=Yes) 0.122990 · historical Churn No

Local TreeSHAP plot for 0295-PPHDO — 0295-PPHDO · P(Churn=Yes) 0.924460 · historical Churn Yes

Local TreeSHAP plot for 5787-KXGIY — 5787-KXGIY · P(Churn=Yes) 0.006431 · historical Churn No

The same three rows, always listed. Plots above follow the selection.
Customer	Why this row	Historical Churn	P(Churn=Yes)	Largest original field
5343-SGUBI	First held-out row with numeric TotalCharges	No	0.122990	Contract = One year, -0.511087
0295-PPHDO	Highest held-out probability	Yes	0.924460	Contract = Month-to-month, 0.870800
5787-KXGIY	Lowest held-out probability	No	0.006431	Contract = Two year, -0.886617