# 018. Campaign contact saturation

**Question:** How does observed subscription vary with the number of campaign contacts?

## Result

The largest computed metric is 0.146 for (0.0, 1.0]; the smallest is 0.0393 for (10.0, inf]. Metric: rate (Subscription share).

Campaign includes the recorded contact. This association cannot estimate the effect of placing one more call.

![Campaign contact saturation](outputs/chart.png)

| contact_band | events | n | rate | wilson_lower | wilson_upper |
| --- | --- | --- | --- | --- | --- |
| (0.0, 1.0] | 2561 | 17544 | 0.146 | 0.1408 | 0.1513 |
| (1.0, 2.0] | 1401 | 12505 | 0.112 | 0.1066 | 0.1177 |
| (10.0, inf] | 47 | 1196 | 0.0393 | 0.02968 | 0.05187 |
| (2.0, 3.0] | 618 | 5521 | 0.1119 | 0.1039 | 0.1205 |
| (3.0, 5.0] | 456 | 5286 | 0.08627 | 0.07899 | 0.09414 |
| (5.0, 10.0] | 206 | 3159 | 0.06521 | 0.05712 | 0.07436 |

The chart shows 6 of 6 result rows; the table previews the first 6 in the analysis-defined order. [Download the full result table](outputs/results.csv). Numerical values are computed from the source; missing results stay unavailable.

## Method

Bounded contact-count bands and binomial rate intervals.

The study uses shared source preparation and reusable statistical routines. Its specific transformations are in [analysis.py](analysis.py), and common model/evaluation code is in [portfolio/methods.py](../../portfolio/methods.py). The [notebook](analysis.ipynb) executes the study and displays the saved results.

## Decision and limitations

Investigate diminishing response while considering that difficult-to-convert clients may receive more calls.

Observational marketing records do not identify campaign uplift. Month and row order are not precise timestamps; repeated-client identifiers are unavailable. Models are research diagnostics, not financial eligibility or automated contact decisions. 

Related studies may share observations or holdouts. These are focused analytical studies, not independent replications or deployed business systems. Any model refinements informed by these results need new untouched evaluation data. No commercial impact is inferred from an association or backtest.

## Reproduce

From the repository root, after installing `requirements.txt`:

```powershell
python projects/018-campaign-contact-saturation/analysis.py
```

Source data are downloaded automatically if absent. Original archives are retained unchanged and checked by SHA-256. The cleaned cache normalizes column names; field-specific changes are visible in [data preparation](../../portfolio/data.py). Runtime evidence is in [receipt.json](outputs/receipt.json).

## Source

[Bank Marketing](https://archive.ics.uci.edu/dataset/222/bank+marketing), Moro, Rita and Cortez (2014). [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). Source data are transformed and aggregated in this study. [Source provenance](../../data/provenance/bank.json) and [prepared-data audit](../../data/provenance/bank_prepared.json) record the downloaded files, field coverage and hashes.