Edmonds–Pruhs protocol
fair division protocol
Edmonds–Pruhs protocol is a protocol for fair cake-cutting. Its goal is to create a partially proportional division of a heterogeneous resource among n people, such that each person receives a subset of the cake which that person values as at least 1/an of the total, where
a
≥
10
{\displaystyle a\geq 10}
is some sufficiently large constant. It is a randomized algorithm whose running time is O(n) with probability close to 1. The protocol was developed by Jeff Edmonds and Kirk Pruhs, who later improved it in joint work with Jaisingh Solanki.
Motivation
A proportional division of a cake can be achieved using the recursive halving algorithm in time O(n log n). Several hardness results show that this run-time is optimal under a wide variety of assumptions. In particular, recursive halving is the fastest possible algorithm for achieving full proportionality when the pieces must be contiguous, and it is the fastest possible deterministic algorithm for achieving even partial proportionality and even when the pieces are allowed to be disconnected. One case which is not covered by the hardness results is the case of randomized algorithms, guaranteeing only partial proportionality and with possibly disconnected pieces. The Edmonds–Pruhs protocol aims to provide an algorithm with run-time O(n) for this case.
The protocol
The general scheme is as follows:
Each partner privately partitions the cake to an pieces of equal subjective value.
The public source identifies “Edmonds–Pruhs protocol” as fair division protocol. This brief keeps that definition visible, then builds a research path around Edmonds, Pruhs and protocol.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Edmonds–Pruhs protocol”, the useful work is to connect “fair division protocol” to the records capable of establishing context and consequence.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Nov 24, 2025. The linked authority identifier is Q18206736. None of the 0 selected statements returned an explicit reference.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Edmonds–Pruhs protocol”, its source revision and the description used here.
- Expand the search: follow Edmonds–Pruhs protocol primary sources, Edmonds–Pruhs protocol archive and Edmonds research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Edmonds–Pruhs protocol”?
- Which cited source is closest to the event, object or claim?
- Which institution is responsible for the underlying evidence?
Search terms from this dossier
This entry incorporates text from “Edmonds–Pruhs protocol” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.