Abstract
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 We study the domination monoid in various classes of structures arising from henselian valuations,
 including 
-expansions
 of henselian valued fields of equicharacteristic
 
 (and, more generally, of
 benign valued fields), 
-adically
 closed fields, monotone D-henselian differential valued fields with many constants,
 regular ordered abelian groups, and pure short exact sequences of abelian structures.
 We obtain Ax–Kochen–Ershov-type reductions to suitable fully embedded
 families of sorts in quite general settings, and full computations in concrete
 ones.
  
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              Keywords
              
                model theory, invariant types, domination monoid, valued
                fields, ordered abelian groups
               
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              Mathematical Subject Classification
              
                Primary: 03C45
               
              
                Secondary: 03C60, 03C64, 12J10, 12L12
               
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              Milestones
              
                Received: 10 November 2021
               
              
                Revised: 13 February 2024
               
              
                Accepted: 14 February 2024
               
              
                Published: 30 April 2024
               
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            | © 2024 The Author(s), under
            exclusive license to MSP (Mathematical Sciences Publishers).
            Distributed under the Creative Commons
            Attribution License 4.0 (CC BY). | 
           
         
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