How it works

Peer Revenue is a play-money stock market in words. Each listing is a word scientists use in their papers. Shareholders are paid every day the word turns up in new arXiv papers, and prices move as players buy and sell.

Listings

A listing is one word plus its plural or irregular forms. For example, $PHOT counts photon and photons, but not photonic. Each word's page lists exactly which forms count.

Hits

Every day we collect every new paper on arXiv: its title, abstract and categories. A hit is one use of a listing's word in a title or abstract, so a paper that says "photon" five times makes five hits.

• Text is lowercased, accents are removed (Schrödinger counts as schrodinger) and LaTeX maths is ignored.
• Hyphens and digits split words: "photon-photon" is two hits, and "COVID-19" counts as covid.
• A paper belongs to the day its first version was submitted. Later versions don't count again.

Settled days

arXiv announces papers a day or more after they're submitted, and Friday's papers aren't all out until Tuesday. So a day is settled 4 days later, once its papers have been announced. Only settled days pay dividends and appear on charts. Occasionally a paper held in moderation adds a few hits to a day after it settles; dividends already paid stand.

Dividends

For each settled day, every share earns 0.01 credits per hit. A word with 300 hits that day pays 3 credits a share. Dividends go automatically to whoever holds shares when the day's payout runs.

Yield, shown on the market pages, is the latest settled day's dividend per share divided by the current price. Weekends bring about half a weekday's papers, so a day's yield swings through the week.

Prices

There are no order books. Each listing has a pool of credits and shares run by an automated market maker. Buying takes shares out of the pool, so the price rises; selling puts them back, so it falls. The price is the pool's credits divided by its shares.

• Bigger trades move the price further. The trade form shows exactly what you'll get before you confirm, and you set a maximum slippage in case someone else trades first.
• Each trade pays a 0.5% fee, and no single trade can take more than 10% of a pool.
• Every listing starts with a pool of 100,000 credits, so a trade of a given size moves a busy word and a quiet one by the same amount.
• A new listing's first price (its IPO) is set so that, at its average hits over the last 30 settled days, dividends would repay the price in about 200 days.

Your account

• Everyone starts with 10,000 credits. Credits are play money: they can't be bought, sold or withdrawn.
• You sign in with a link sent to your email; there's no password. You pick the name you play under, and the game adds et al. Your email is never shown. See Privacy.
• Your portfolio's marked value is your cash plus what your holdings would fetch if you sold them all now, after price impact and fees. The leaderboard ranks players by the same number, so pushing up the price of a thinly traded word doesn't help.

News

The News page is written by a desk with a loose relationship to seriousness, but its figures are exact: paper counts, the fields and words moving against a usual week, and links to the papers themselves.

Where the data comes from

Paper metadata comes from arXiv's public OAI-PMH interface, collected a few requests a day. arXiv metadata is released under CC0. Thank you to arXiv for use of its open access interoperability. Peer Revenue is not affiliated with or endorsed by arXiv.