# Madelon: original UCI challenge splits

[Browse datasets](<../../>) 

`datamonger:guyon2004-madelon@1` · Registry `1.4.0`. Default version in this registry. 

Synthetic binary classification benchmark preserving all 500 features and the original training, validation, and unlabeled test splits. 

<a id="dimensions-and-tasks"></a>

## Dimensions and tasks

| Task | Type | Split | Samples | Predictors |
| --- | --- | --- | --- | --- |
| default | classification | test | 1,800 | 500 |
| default | classification | train | 2,000 | 500 |
| default | classification | validation | 600 | 500 |

Predictor counts follow each task's feature selection and exclude targets and identifiers. Sample counts are reported separately for each split. 

<a id="retrieve"></a>

## Retrieve

These examples pin both the dataset version and the registry's exact index. An uncached dataset requires network access to its source. The CLI retrieves verified artifacts. The language clients also decode them. 

<a id="python"></a>

### Python

```python
from datamonger import Registry, fetch_data

registry = Registry(
    release="1.4.0",
    index_sha256="ef83679266af9fcbb9ea194acdfb9bb6c380b440a574fc2ee7292899c5102909",
    index_url="https://github.com/jolars/datamonger/releases/download/registry-v1.4.0/index.json",
)
data = fetch_data("datamonger:guyon2004-madelon@1", registry=registry)
```

<a id="r"></a>

### R

```r
library(datamonger)

registry <- registry_selector(
  release = "1.4.0",
  index_sha256 = "ef83679266af9fcbb9ea194acdfb9bb6c380b440a574fc2ee7292899c5102909",
  index_url = "https://github.com/jolars/datamonger/releases/download/registry-v1.4.0/index.json"
)
data <- fetch_data("datamonger:guyon2004-madelon@1", registry = registry)
```

<a id="julia"></a>

### Julia

```julia
using Datamonger

registry = registry_selector(
    "1.4.0",
    "ef83679266af9fcbb9ea194acdfb9bb6c380b440a574fc2ee7292899c5102909",
    "https://github.com/jolars/datamonger/releases/download/registry-v1.4.0/index.json",
)
data = fetch_data("datamonger:guyon2004-madelon@1"; registry=registry)
```

<a id="cli"></a>

### CLI

```sh
cat > datamonger-registry.json <<'JSON'
{
  "index_sha256": "ef83679266af9fcbb9ea194acdfb9bb6c380b440a574fc2ee7292899c5102909",
  "index_url": "https://github.com/jolars/datamonger/releases/download/registry-v1.4.0/index.json",
  "release": "1.4.0",
  "schema_version": 1
}
JSON
datamonger --selector datamonger-registry.json fetch 'datamonger:guyon2004-madelon@1'
```

<a id="representation-and-variables"></a>

## Representation and variables

Tabular data with a dense representation. Decoder: `named-splits` version 1. 

| Component | Kind | Type | Shape |
| --- | --- | --- | --- |
| train/x1 | vector | int64 | 2,000 |
| train/x2 | vector | int64 | 2,000 |
| train/x3 | vector | int64 | 2,000 |
| train/x4 | vector | int64 | 2,000 |
| train/x5 | vector | int64 | 2,000 |
| train/x6 | vector | int64 | 2,000 |
| train/x7 | vector | int64 | 2,000 |
| train/x8 | vector | int64 | 2,000 |
| train/x9 | vector | int64 | 2,000 |
| train/x10 | vector | int64 | 2,000 |
| train/x11 | vector | int64 | 2,000 |
| train/x12 | vector | int64 | 2,000 |
| train/x13 | vector | int64 | 2,000 |
| train/x14 | vector | int64 | 2,000 |
| train/x15 | vector | int64 | 2,000 |
| train/x16 | vector | int64 | 2,000 |
| train/x17 | vector | int64 | 2,000 |
| train/x18 | vector | int64 | 2,000 |
| train/x19 | vector | int64 | 2,000 |
| train/x20 | vector | int64 | 2,000 |
| train/x21 | vector | int64 | 2,000 |
| train/x22 | vector | int64 | 2,000 |
| train/x23 | vector | int64 | 2,000 |
| train/x24 | vector | int64 | 2,000 |
| train/x25 | vector | int64 | 2,000 |
| train/x26 | vector | int64 | 2,000 |
| train/x27 | vector | int64 | 2,000 |
| train/x28 | vector | int64 | 2,000 |
| train/x29 | vector | int64 | 2,000 |
| train/x30 | vector | int64 | 2,000 |

Showing 30 of 1,502 components. The [complete registry record](<../../../assets/87b3236997471e4734bdb82a9d6feafdc07ef5c2ba332a4c8e78f37e884f75a3.bin>) contains every variable name and task binding. 

<a id="preprocessing"></a>

## Preprocessing

<a id="upstream"></a>

### Upstream

Status: documented. 

**synthetic-generation.** Generate five informative dimensions, 15 redundant linear combinations, and 480 distractors; randomize feature and observation order. 

Evidence: [https://archive.ics.uci.edu/dataset/171/madelon](<https://archive.ics.uci.edu/dataset/171/madelon>) 

<a id="datamonger"></a>

### Datamonger

Status: none. 

Lossless CSV conversion and gzip compression only. Preserve all values, labels, row and feature order, and splits. 

Evidence: curation/guyon2004-madelon/1/prepare.py 

<a id="provenance-and-citation"></a>

## Provenance and citation

Provider: Datamonger; derived from UCI. Upstream name: Madelon. Retrieved: 2026-10-26. 

[Original source](<https://archive.ics.uci.edu/dataset/171/madelon>) 

Authors: Isabelle Guyon. 

Guyon, I. (2004). Madelon \[Dataset\]. UCI Machine Learning Repository. [https://doi.org/10.24432/C5602H](<https://doi.org/10.24432/C5602H>). 

Madelon: original UCI challenge splits (Datamonger representation, version 1). [https://doi.org/10.5281/zenodo.23665387](<https://doi.org/10.5281/zenodo.23665387>). 

<a id="license"></a>

## License

CC-BY-4.0 

[License information](<https://creativecommons.org/licenses/by/4.0/>) 

UCI explicitly licenses Madelon under CC BY 4.0: [https://archive.ics.uci.edu/dataset/171/madelon](<https://archive.ics.uci.edu/dataset/171/madelon>). 

<a id="artifacts"></a>

## Artifacts

Total download: 2.6 MiB. Sizes describe the distributed files, including any compression. 

| Artifact | Format | Compression | Size | Distribution | Preservation |
| --- | --- | --- | --- | --- | --- |
| train | csv | gzip | 1.2 MiB | mirror | durable |
| validation | csv | gzip | 365.9 KiB | mirror | durable |
| test | csv | gzip | 1.1 MiB | mirror | durable |

[train: mirror](<https://zenodo.org/records/23665387/files/train.csv.gz?download=1>) 

[Preservation deposit](<https://doi.org/10.5281/zenodo.23665387>) 

[validation: mirror](<https://zenodo.org/records/23665387/files/validation.csv.gz?download=1>) 

[Preservation deposit](<https://doi.org/10.5281/zenodo.23665387>) 

[test: mirror](<https://zenodo.org/records/23665387/files/test.csv.gz?download=1>) 

[Preservation deposit](<https://doi.org/10.5281/zenodo.23665387>) 

<a id="versions-in-this-registry"></a>

## Versions in this registry

[1](<1>) (default) 

<a id="registry-record"></a>

## Registry record

Download the [complete registry record](<../../../assets/87b3236997471e4734bdb82a9d6feafdc07ef5c2ba332a4c8e78f37e884f75a3.bin>), [registry selector](<../../../assets/34c66958a7fbdc23b69bacece50c1f1e9a097760400133967cecb6086963cdb1.bin>), or [full registry index](<https://github.com/jolars/datamonger/releases/download/registry-v1.4.0/index.json>). 

Index SHA-256: `ef83679266af9fcbb9ea194acdfb9bb6c380b440a574fc2ee7292899c5102909`.