README.md

---
license: odc-by
task_categories:
  - text-generation
language:
  - code
size_categories:
  - 1B<n<10B
tags:
  - curated
  - starcoderdata
  - code
  - structured-data
  - multi-task-filter
---

# StarCoderData Curated

A curated subset of [StarCoderData](https://huggingface.co/datasets/bigcode/starcoderdata)
optimised for training a 500M parameter model focused on structured data output
(JSON generation, function calling, schema compliance).

## Dataset Summary

- **Total code files:** 5,203,508
- **Total tokens:** 3.9B (target: 3.5B)
- **Classifier-scored files:** 1,553,596 (1.7B tokens)
- **Non-classified files:** 3,649,912 (2.2B tokens) — filtered by heuristics, not the classifier
- **Source:** bigcode/starcoderdata
- **Classifier:** [mdonigian/code-curator-v1](https://huggingface.co/mdonigian/code-curator-v1) (UniXcoder-base, multi-task)
- **Curation:** Per-language-slice filtering + compression ratio pre-filter + MinHash deduplication

## Filtering Strategy

Different language groups need different curation approaches. Not every slice
goes through the GPU classifier — schema languages and GitHub issues are filtered
with cheaper heuristics because the classifier was trained on general-purpose code
and isn't the right tool for inherently structured formats.

**All slices** share these pre-filters:
- zlib compression ratio < 0.10 (catches extreme repetition)
- MinHash LSH deduplication (128 perms, 5-line shingles, 0.7 Jaccard threshold)

### Classifier-Scored Slices (relevance_filter)

These languages were scored by the multi-task classifier. Files were ranked by
structured data relevance and filtered to keep only those with relevance ≥ 2.0
and quality ≥ 1.5, sampled down to the per-slice token budget:

- **TypeScript**: ~600M tokens — strong type system, filter by SD relevance ≥ 2
- **Python**: ~600M tokens — filter by SD relevance ≥ 2
- **Rust/Go/Java**: ~600M tokens — strongly typed, filter by SD relevance ≥ 2

### Non-Classified Slices

These languages were **not** run through the classifier. Their `quality`,
`structured_data`, and `content_type` columns contain default placeholder values
(0.0 / "unclassified") and should be ignored:

- **Schema languages** (JSON/YAML/SQL/protobuf/thrift/XSLT): ~800M tokens — inherently structured data formats; quality floor + random sample to budget
- **GitHub Issues** (technical): ~500M tokens — keyword filter matching structured-data topics (JSON, schema, API, protobuf, gRPC, etc.)
- **General code** (78 other languages): ~1B tokens — random sample for language diversity; quality floor only

## Language Slice Distribution

| Slice | Strategy | Languages | Target | Actual | % of Target |
|-------|----------|-----------|--------|--------|-------------|
| schema_languages | light_filter | json, yaml, sql, protocol-buffer +2 more | 800M | 799M | 99.9% |
| typescript | relevance_filter | typescript | 600M | 598M | 99.7% |
| python | relevance_filter | python | 600M | 594M | 99.1% |
| rust_go_java | relevance_filter | rust, go, java | 600M | 485M | 80.8% |
| github_issues | keyword_filter | github-issues-filtered-structured | 500M | 426M | 85.2% |
| general_code | light_filter | ada, agda, alloy, antlr +74 more | 1000M | 999M | 99.9% |


## Classifier-Scored Slices — Detail

The quality and structured data scores below apply **only** to the 1,553,596 files
(1.7B tokens) that went through the classifier. Non-classified slices
are excluded from these statistics.

| Slice | Files | Tokens | Avg Quality | Avg SD Relevance |
|-------|-------|--------|-------------|------------------|
| typescript | 841,426 | 598M | 3.81 | 2.88 |
| python | 567,721 | 594M | 3.71 | 2.73 |
| rust_go_java | 144,438 | 485M | 3.97 | 3.07 |

### Content Group Distribution (classifier-scored files only)

| Group | % of Classified Tokens | Tokens | Files |
|-------|-----------------------|--------|-------|
| Library/Package | 64.3% | 1,079,381,502 | 1,075,672 |
| Application | 3.4% | 56,360,750 | 118,200 |
| Script/CLI | 1.1% | 17,853,662 | 24,871 |
| Test Code | 5.5% | 91,370,763 | 48,003 |
| Config/Data/Generated/Other | 25.8% | 432,393,146 | 286,850 |


### Structured Data Relevance (classifier-scored files only)

The strongest classifier signal (Spearman 0.81 on held-out data). SD2+ files
contain significant structured data patterns (API endpoints, JSON parsing,
schema definitions, etc.).

Quality mean: 3.79, Median: 3.88.

| Level | Range | Target % | Actual % | Files |
|-------|-------|----------|----------|-------|
| SD0 | [0.0, 0.5) | 10.0% | 0.0% | 0 |
| SD1 | [0.5, 1.5) | 20.0% | 0.0% | 0 |
| SD2 | [1.5, 2.5) | 35.0% | 3.2% | 49,213 |
| SD3 | [2.5, 3.5) | 35.0% | 96.8% | 1,504,383 |


### Quality Distribution (classifier-scored files only)

| Level | Description | Files |
|-------|-------------|-------|
| 1 | Broken/gibberish | 0 |
| 2 | Functional but poor | 42,668 |
| 3 | Decent | 129,945 |
| 4 | Good | 1,380,674 |
| 5 | Excellent | 309 |


## Non-Classified Slices — Detail

These slices were filtered using heuristics. The classifier columns (`quality`,
`structured_data`, `content_type`) are set to defaults and **do not reflect
actual code quality** — the filtering was done by other means:

| Slice | Strategy | Files | Tokens | How Filtered |
|-------|----------|-------|--------|-------------|
| schema_languages | light_filter | 2,203,233 | 799M | Quality floor (≥1.5) + token budget, randomly sampled |
| github_issues | keyword_filter | 485,384 | 426M | Keyword match for structured-data topics + quality floor |
| general_code | light_filter | 961,295 | 999M | Quality floor (≥1.5) + token budget, randomly sampled |


## Programming Languages

| Language | % Tokens | Files |
|----------|----------|-------|
| typescript | 15.3% | 841,426 |
| python | 15.2% | 567,721 |
| github-issues-filtered-structured | 10.9% | 485,384 |
| markdown | 8.9% | 351,728 |
| json | 8.7% | 1,124,326 |
| go | 8.5% | 73,899 |
| sql | 5.9% | 121,035 |
| javascript | 5.8% | 281,216 |
| yaml | 5.8% | 957,872 |
| java | 3.2% | 57,787 |
| c-sharp | 3.0% | 114,063 |
| html | 2.9% | 53,527 |
| c | 2.8% | 75,899 |
| haskell | 2.2% | 84,862 |
| rust | 0.7% | 12,752 |


## Token Count Distribution

| Percentile | Tokens |
|------------|--------|
| P10 | 55 |
| P25 | 111 |
| P50 (median) | 255 |
| P75 | 631 |
| P90 | 1,416 |
| Mean | 749 |

## Schema

Each row contains:

| Field | Type | Description |
|-------|------|-------------|
| `content` | string | Source code text |
| `lang` | string | Programming language |
| `size` | int | File size in bytes |
| `token_count` | int | Estimated token count (size // 4) |
| `quality` | float | Code quality score 1-5 (**classifier-scored slices only**; 0.0 for non-classified) |
| `structured_data` | float | Structured data relevance 0-3 (**classifier-scored slices only**; 0.0 for non-classified) |
| `content_type` | string | Content type — 9 classes (**classifier-scored slices only**; "unclassified" for non-classified) |
| `language_slice` | string | Language slice name (use this to filter by curation strategy) |
| `relevance_score` | float | Composite relevance score (**classifier-scored slices only**; 0.0 for non-classified) |

> **Tip:** To work with only classifier-scored data, filter on
> `language_slice` in `{"typescript", "python", "rust_go_java"}`.

## Methodology

1. **Download:** All language folders from `bigcode/starcoderdata`.
2. **Classification:** Multi-task UniXcoder-base model (3 heads: quality, SD relevance,
   content type) runs on TypeScript, Python, Rust, Go, and Java
   Schema languages, GitHub issues, and general code skip this step.
3. **Pre-filtering:** zlib compression ratio filter removes repetitive boilerplate
   before GPU inference.
4. **Filtering:** Per-slice strategy — relevance-based ranking for classified languages,
   keyword matching for GitHub issues, random sampling for schema/general code. All
   slices enforce a quality floor.
5. **Deduplication:** MinHash LSH (128 perms, 5-line shingles, 0.7 Jaccard threshold).
   Highest-relevance file kept from each cluster.