Every term explained

It is the only honest way to compare two traders. Profit and loss mixes skill with size and luck; this measures whether the probabilities they were paying were right.

Lower is better. 0.25 is what you score by calling everything even money, so anything above that is worse than having no opinion. Below 0.12 is a strong record. It needs at least eight settled positions before it means anything.

Scoring against a flat 50% flatters anybody who trades longshots: always saying no to 5% contracts scores beautifully and proves nothing. This asks the harder question.

Positive means the selection added something. Negative means you would have done better betting your own hit rate on everything without looking.

You can be well calibrated and lose money, or badly calibrated and win. But a trader who is over-confident in one band has a specific, fixable problem, and the average alone will not show you where it is.

A gap of zero means the price paid matched what happened. Positive means under-confident, negative means over-confident. The band it happens in is the useful part.

The quoted spread describes the first contract. Everything after it comes from further down the book, and on these venues the top level is often a handful of contracts. A tight quote on a thin book is a worse market than a wider quote on a deep one.

Compare it to the quoted spread. Two or three times wider at a size you would actually trade is common and worth knowing before you take the position rather than while you are leaving it.

It is the cost of quoting to people who know more than you do, and it is the part a wider spread does not fix. A market where every fill is followed by the price running away is one that loses money to quote at any width.

Higher is worse for a market maker. Subtract it from the effective spread and what is left is what a maker actually keeps.

This is the number that decides whether quoting a market pays, and it is invisible from the price. Several markets that look perfectly quotable lose money on every round trip.

Positive means quoting it pays. Negative means it does not, however wide you quote, because the loss is information rather than width.

Two venues disagreeing is normal and mostly uninteresting: correctly matched contracts agree to within about two points, and fees are wider than that. Net edge is the part that would survive actually doing it.

Frequently negative, which is the honest answer. A positive figure is worth checking against whether the two contracts really do resolve identically before it is worth anything else.

Two markets quoting the same price are not the same market if one is a thousand small positions agreeing and the other is one wallet holding four fifths of a side. The price says nothing about which you are looking at.

A top holder above half the side means the price there is substantially one participant’s opinion. Their exit becomes the market’s liquidity problem as well as their own.

Neither state shows in the price, and both change what a position is worth. A disputed market is not settled, and the result the price is anticipating may not stand.

Proposed means decided unless somebody objects. Disputed means somebody has. Polymarket only: Kalshi settles internally and publishes nothing equivalent, so silence there means unknown rather than safe.

A price level is close to no information on its own. That a market sits at 48% tells you little; that the crowd revised it twenty points today is a story, and the question worth asking is what they learned.

Measured against recorded history rather than the venue, because neither venue publishes it. That means the window is only as long as collection has been running.

Depth is the difference between a position you can leave and one you are stuck in. It decides what any view is actually worth to you, because an edge you cannot exit at is not an edge.

Read it against the size you would trade rather than in the abstract. The number that matters is whether the book fills you on both sides.

It is what makes a market expensive to be wrong in quickly. A market that moves on small size punishes anybody who has to get out in a hurry, regardless of what the spread looked like.

Higher means thinner. It is most useful compared between markets rather than read as an absolute.

An edge has to survive being locked up until settlement, so the same difference in price is worth very different amounts depending on whether it resolves next week or in 2028.

This is why cross-venue gaps are shown annualised as well as absolute: two points over a month and two points over three years are not the same trade.

A price nobody has taken in size is a quote rather than a consensus. Every other reading on a market is weaker when little has changed hands.

Lifetime volume is used consistently across both venues. It favours long-dated contracts, which accumulate it simply by existing.