OpenMarket

Read a small OpenMarket Polymarket dataset sample

This check reads one frozen demo file: lag_pairs_ms.parquet, 25,171 bytes and 1,769 paired observations. It checks actual field types, timestamp coverage and the lead–lag formula before you attempt the full research archive.

Executed by PredAtlas on October 22, 2026, using Python 3.12.2 and PyArrow 19.0.1 on macOS arm64. This is a bounded data check, not a rerun of the paper or a full product review.

Download only the demo file

Use a new local folder with Python 3.12 and curl installed. The dataset URL pins a specific revision. The download is capped at 1 MiB; the checker verifies the SHA-256 below and refuses more than 10,000 rows. It makes no network or trading calls.

python3 -m venv .venv
.venv/bin/python -m pip install pyarrow==19.0.1
curl --fail --location --max-time 60 --max-filesize 1048576 \
  'https://huggingface.co/datasets/gregyoung14/openmarket-btc-polymarket/resolve/74502466d1a7cef56395bfd8d0b465fbebc849cf/lag_pairs_ms.parquet' -o lag_pairs_ms.parquet
curl --fail --max-time 30 --max-filesize 65536 \
  'https://predatlas.com/examples/openmarket-sample-check.py' -o openmarket-sample-check.py
.venv/bin/python openmarket-sample-check.py lag_pairs_ms.parquet

Inspect the complete checker before running it. Expected sample SHA-256: dd5a7b4c1f0ab82fa355a86325459359399f21029ee3a7eb578c0e994e4ad2d4.

Observed output

rows=1769; bytes=25171; missing_required=0
paired_at_utc=2026-05-14T14:58:42.554Z..2026-05-14T14:59:28.138Z
binance_source_utc=2026-05-14T14:58:27.479Z..2026-05-14T14:59:17.062Z; polymarket_source_utc=2026-05-14T14:58:27.235Z..2026-05-14T14:59:16.961Z
lead_lag_ms=-613..508; formula_mismatches=0
quality_flag:string={'medium': 571, 'tight': 1078, 'wide': 120}; side_label=['DOWN', 'UP']

The pairing timestamps span 45.584 seconds on May 14, 2026. Source-event timestamps precede these pairing timestamps; they are different clocks and must not be treated as interchangeable event times. All 1,769 rows satisfy lead_lag_ms = polymarket_source_ts_ms - binance_source_ts_ms.

Two schema details to check before filtering

In this file, quality_flag is a string with tight, medium and wide values. The reference README describes an integer flag. Likewise, actual side_label values are uppercase UP and DOWN, while the reference shows lowercase labels. Inspect the file schema and values instead of assuming a numeric quality filter or lowercase match.

The file contains integer IDs and millisecond timestamps; text market, side, quality and date fields; and floating-point prices. This check does not validate foreign keys against the other sample tables, complete order books, clock synchronization, executable fills or trading returns. Positive lead–lag means a later Polymarket source timestamp, not a demonstrated tradable edge. This short demo is not representative of the full archive’s coverage or gaps.

Source and attribution: Gregory Young, OpenMarket BTC Polymarket, pinned dataset revision, root v0.1-sample demo. Dataset card declares Apache-2.0; see the source license and v0.5.2 dataset reference. Only derived checks are shown here; download the original file from its publisher.