eprintid: 10152229 rev_number: 8 eprint_status: archive userid: 699 dir: disk0/10/15/22/29 datestamp: 2022-07-20 16:14:39 lastmod: 2022-07-20 16:15:46 status_changed: 2022-07-20 16:14:39 type: proceedings_section metadata_visibility: show sword_depositor: 699 creators_name: Ben-Basat, Ran creators_name: Mitzenmacher, Michael creators_name: Vargaftik, Shay title: How to send a real number using a single bit (and some shared randomness) ispublished: pub divisions: C05 divisions: F48 divisions: B04 divisions: UCL keywords: Randomized Algorithms, Approximation Algorithms, Shared Randomness, Distributed Protocols, Estimation, Subtractive Dithering note: © Ran Ben Basat, Michael Mitzenmacher, and Shay Vargaftik; licensed under Creative Commons License CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/). abstract: We consider the fundamental problem of communicating an estimate of a real number x ∈ [0,1] using a single bit. A sender that knows x chooses a value X ∈ {0,1} to transmit. In turn, a receiver estimates x based on the value of X. The goal is to minimize the cost, defined as the worst-case (over the choice of x) expected squared error. We first overview common biased and unbiased estimation approaches and prove their optimality when no shared randomness is allowed. We then show how a small amount of shared randomness, which can be as low as a single bit, reduces the cost in both cases. Specifically, we derive lower bounds on the cost attainable by any algorithm with unrestricted use of shared randomness and propose optimal and near-optimal solutions that use a small number of shared random bits. Finally, we discuss open problems and future directions. date: 2021 date_type: published publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik official_url: https://doi.org/10.4230/LIPIcs.ICALP.2021.25 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1853867 doi: 10.4230/LIPIcs.ICALP.2021.25 isbn_13: 978-3-95977-195-5 lyricists_name: Ben Basat, Shlomi Ran lyricists_id: SRBEN76 actors_name: Flynn, Bernadette actors_id: BFFLY94 actors_role: owner full_text_status: public pres_type: paper series: Leibniz International Proceedings in Informatics (LIPIcs) publication: ICALP 2021 place_of_pub: Dagstuhl, Germany pagerange: 1-20 event_title: The 48th International Colloquium on Automata, Languages, and Programming (ICALP 2021) book_title: Proceedings of the 48th International Colloquium on Automata, Languages, and Programming (ICALP 2021) citation: Ben-Basat, Ran; Mitzenmacher, Michael; Vargaftik, Shay; (2021) How to send a real number using a single bit (and some shared randomness). In: Proceedings of the 48th International Colloquium on Automata, Languages, and Programming (ICALP 2021). (pp. pp. 1-20). Schloss Dagstuhl - Leibniz-Zentrum für Informatik: Dagstuhl, Germany. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10152229/1/LIPIcs-ICALP-2021-25.pdf