Anderson, B. D.O.Deistler, M.Scherrer, W.2025-05-302025-05-300005-1098ORCID:/0000-0002-1493-4774/work/174739572http://www.scopus.com/inward/record.url?scp=0030188945&partnerID=8YFLogxKhttps://hdl.handle.net/1885/733754968This paper examines and refutes a conjecture to the effect that the solution set for a general (real) static errors-in-variables problem is a finite union of sets that are described by a finite number of linear inequalities. The conjecture is disproved by detailed examination of particular errors-in-variables problems with four variables. The solution set in this case is described by five surfaces, all intersecting in straight lines, but in general one of these surfaces is not flat.Acknowledgements-B.D.O.A. wishes to acknowledget he funding of the activitieso f the CooperativeR esearchC enter for Robust and Adaptive Systems by the Australian Commonwealth Government under the Cooperative Re-searchC enter Program.M .D. and W.S. wish to acknowledge support by the-Austrian Fonds zur Fiirderung dir wissenschaftlichenF orschung Projekt P9176-PHY, and by the EC-SCIENCE project European Research Network SystemI dentification.5enErrors-in-variablesLinear systemsNoisy inputsSymmetric modellingSystem identification199610.1016/0005-1098(96)00032-50030188945