README.md

---
license: apache-2.0
task_categories:
  - tabular-classification
  - tabular-regression
language:
  - en
size_categories:
  - 100K<n<1M
configs:
  - config_name: stage1
    data_files:
      - split: train
        path: data/stage1/**/*.parquet
  - config_name: stage2
    data_files:
      - split: train
        path: data/stage2/**/*.parquet
  - config_name: stage3
    data_files:
      - split: train
        path: data/stage3/**/*.parquet
  - config_name: stage4
    data_files:
      - split: train
        path: data/stage4/**/*.parquet
---

# CleanTabLib

A cleaned and processed version of [TabLib](https://huggingface.co/datasets/approximatelabs/tablib-v1-full), a large-scale collection of tabular data from diverse sources (GitHub, CommonCrawl, and others). Each table has been filtered for quality, columns classified as categorical or continuous, and optionally normalized/encoded for direct use in machine learning.

## Quick Start

```python
from datasets import load_dataset
import pyarrow as pa

ds = load_dataset("alexodavies/cleantablib", "stage4")

for example in ds['train']:
    table_id = example['table_id']
    metadata = example['metadata']

    # Deserialize the Arrow IPC bytes back to a table
    reader = pa.RecordBatchStreamReader(example['arrow_bytes'])
    table = reader.read_all()
    df = table.to_pandas()
```

## Dataset Structure

Files are organized into sharded subdirectories to stay within platform limits:

```
data/
  stage1/
    shard_00/
      batch_00001.parquet
      ...
    shard_01/
      ...
  stage2/
    shard_00/
      batch_00001.parquet
      ...
    shard_01/
      ...
  stage3/
    shard_00/
      batch_00001.parquet
      ...
    shard_01/
      ...
  stage4/
    shard_00/
      batch_00001.parquet
      ...
    shard_01/
      ...
```

Each stage is an independent config. Use `load_dataset(repo, config_name)` to load a specific stage. Most users will want **stage4** (fully processed) or **stage1** (original filtered tables).

## Dataset Statistics

| Stage | Tables | Files | Size | Rows (mean) | Rows (median) | Cols (mean) | Cols (median) |
|-------|--------|-------|------|-------------|---------------|-------------|---------------|
| stage1 | 2,988,000 | 7,470 | 107.1 GB | 1,042 | 113 | 6 | 4 |
| stage2 | 2,210,180 | 14,879 | 75.2 GB | 1,271 | 116 | 6 | 5 |
| stage3 | 2,210,043 | 14,879 | 92.3 GB | 1,270 | 116 | 6 | 5 |
| stage4 | 2,117,811 | 14,879 | 198.6 GB | 1,232 | 117 | 6 | 5 |

**Pass-through rates:**

- Stage 1 to Stage 2: 74.0%
- Stage 2 to Stage 3: 100.0%
- Stage 3 to Stage 4: 95.8%

### Column Types (stage2)

| Type | Count | % |
|------|-------|---|
| categorical | 3,766,554 | 30.3% |
| ambiguous | 3,526,030 | 28.4% |
| continuous | 3,332,725 | 26.8% |
| likely_text_or_id | 1,808,006 | 14.5% |

### Column Types (stage3)

| Type | Count | % |
|------|-------|---|
| categorical | 3,766,202 | 30.3% |
| ambiguous | 3,525,681 | 28.4% |
| continuous | 3,332,522 | 26.8% |
| likely_text_or_id | 1,807,915 | 14.5% |

### ML Classifications (stage3)

| Classification | Count | % |
|----------------|-------|---|
| categorical | 5,512,597 | 51.9% |
| continuous | 4,550,758 | 42.8% |
| needs_llm_review | 561,050 | 5.3% |

### Classification Sources (stage3)

| Source | Count | % |
|--------|-------|---|
| heuristic | 7,098,724 | 66.8% |
| ml_high | 2,094,239 | 19.7% |
| ml_medium | 870,392 | 8.2% |
| ml_low | 561,050 | 5.3% |

### Column Types (stage4)

| Type | Count | % |
|------|-------|---|
| categorical | 3,718,359 | 30.8% |
| ambiguous | 3,371,838 | 27.9% |
| continuous | 3,284,452 | 27.2% |
| likely_text_or_id | 1,711,168 | 14.2% |

## Processing Pipeline

### Stage 1 — Filter

Basic quality filtering applied to raw TabLib tables:

- Minimum **64 rows**
- Minimum **2 columns**
- Maximum **50% missing values**
- Row count must be >= column count
- Tables exceeding 1 GB estimated memory are skipped
- Duplicate column names are deduplicated

### Stage 2 — Heuristic Classification

Rule-based column type classification:

| Rule | Classification |
|------|----------------|
| Uniqueness < 5% | Categorical |
| Uniqueness > 30% and numeric | Continuous |
| Uniqueness > 95% and non-numeric | Dropped (likely ID/text) |
| Everything else | Ambiguous (sent to Stage 3) |

String columns with numeric-like values (commas, K/M/B suffixes, scientific notation) are converted.

### Stage 3 — ML Classifier

A Random Forest classifier resolves ambiguous columns from Stage 2. It extracts 33 distribution-agnostic features (string length patterns, character distributions, entropy, numeric convertibility) and predicts categorical vs. continuous.

Confidence levels:

- **High** (>0.75): accepted automatically
- **Medium** (0.65-0.75): accepted with lower confidence
- **Low** (<0.65): marked for review, dropped in Stage 4

### Stage 4 — Normalization & Encoding

Final transformations to make data ML-ready:

- **Continuous columns**: z-score normalization (`(x - mean) / std`)
- **Categorical columns**: integer encoding (1, 2, 3, ...)
- **Low-confidence columns**: dropped

All transformation parameters are stored in `metadata` for reversibility.

## Reversing Transformations

Stage 4 metadata contains the parameters needed to undo normalization and encoding:

```python
import pyarrow as pa

# Load a stage4 example
metadata = example['metadata']
reader = pa.RecordBatchStreamReader(example['arrow_bytes'])
table = reader.read_all()
df = table.to_pandas()

# Reverse z-score normalization for a continuous column
norm_params = metadata['stage4_normalized_columns']['my_column']
df['my_column'] = df['my_column'] * norm_params['std'] + norm_params['mean']

# Reverse integer encoding for a categorical column
enc_params = metadata['stage4_encoded_columns']['my_category']
inverse_map = {v: k for k, v in enc_params['mapping'].items()}
df['my_category'] = df['my_category'].map(inverse_map)
```

## Schema

Each row in the parquet files represents one table:

| Column | Type | Description |
|--------|------|-------------|
| `table_id` | string | Unique identifier for the source table |
| `arrow_bytes` | binary | Serialized PyArrow table in IPC streaming format |
| `metadata` | struct | Processing metadata from all pipeline stages |

## Source

Built from [approximatelabs/tablib-v1-full](https://huggingface.co/datasets/approximatelabs/tablib-v1-full). If you use this dataset, please cite the original TabLib work.