I am trying to understand what algorithms/heuristics are used under each of {aggressive, default, fast} emphasis settings both for separators and heuristics? Where in the documentation or the code can I find this information? Is there a way to change what is computed under each of the above settings?
As per my understanding of CPLEX, to avoid painstaking bookkeeping of local constraints and global constraints, CPLEX's modes (aggressive, default and fast) for bound computation doesn't differ much in performance and time. Is it same with SCIP as well? Is SCIP able to maintain separate local and global cuts?
If you open the interactive shell and choose one of the emphasis settings, e.g. set heur emph aggressive SCIP will report back all the changed parameters.
You can only change what these emphasis settings do by changing them in the SCIP code.
I am not sure I understand your question about time for bound computation. Changing the emphasis settings for heuristics and separation in SCIP can definitely change the solving time.
Yes, SCIP can maintain both global and local cuts, if you create a cut in SCIP with SCIPcreateEmptyRowSepa there is a "local"flag that you can set.