# nkjp1m

The manually annotated 1-million word subcorpus of the National Corpus of Polish

## Dataset description
- **Source (upstream):** https://clip.ipipan.waw.pl/NationalCorpusOfPolish
- **Domain:** mixed (balanced reference corpus)
- **Language:** Polish (pl)
- **License:** `CC-BY`
- **Created (range):** 1957-2008 (recorded for 6,581 of 18,381 documents; per-document in the created column)
- **Added:** 2026-06-15

## Licensing — traceable basis
The NKJP download page (clip.ipipan.waw.pl) states the manually annotated 1-million-word subcorpus (Podkorpus Milionowy NKJP 1.2) is available under a CC-BY licence; attribution to the NKJP Consortium (IPI PAN) preserved. The page states 'CC-BY' with no version, normalized to CC-BY-4.0 for SPDX. The CC-BY licence covers the corpus text; NKJP's separate tools are GPL and are not included here.

## Provenance
Downloaded the IPI PAN tarball (NKJP-PodkorpusMilionowy-1.2.tar.gz) directly by src/fetch_njkp.py, one row per TEI <div> passage (its <ab> paragraphs joined by newlines, ellipsis markers stripped). The same minimal gates as build_dynaword.py are applied per passage (drop < 200 chars, drop non-Polish by diacritic ratio, exact sha1 dedup; the OCR gate is inapplicable). Per-document 'created' is the sample's TEI publication date (<date type="published">) where the header records one. Normalized into the DynaWord schema; cl100k token counts via tiktoken (encode_ordinary), and the stats are recomputed from the written parquet.

## Statistics
| documents | characters | tokens (tiktoken proxy) |
| --------: | ---------: | ----------------------: |
|    18,381 |  6,824,905 |               2,601,201 |


## Per-document license metadata
| license | documents |
| ------- | --------: |
| `CC-BY` |    18,381 |

Author metadata present for **18,381** documents. Empty values mean the upstream record did not expose a machine-readable author field.

Statistics were recomputed directly from the released parquet file.

## Filters applied (build_dynaword.py)
Minimal, per Dynaword guidelines (heavy filtering left to downstream use):
- drop documents < 200 chars: **92**
- drop non-Polish (diacritic ratio): **2**
- exact cross-source dedup (sha1): **9**
- OCR alpha-ratio < 0.70 (OCR sources only): **0**
- read 18,484 → kept 18,381

Token counts are a fast tiktoken (cl100k) proxy.