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<p>Hi James,</p>
<p> In addition to Marc's reply, propagations are applied to sub-LPs during strong branching, which essentially add simple variable-bound change cuts. For more details, you may find the function performStrongbranchWithPropagation().</p>
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<p>Best</p>
<p>Liding</p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Scip <scip-bounces@zib.de> on behalf of James Cussens <james.cussens@bristol.ac.uk><br>
<b>Sent:</b> Wednesday, March 5, 2025 12:24:32 PM<br>
<b>To:</b> scip@zib.de<br>
<b>Subject:</b> [SCIP] strong branching and cuts</font>
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As I understand it, when running strong branching on a candidate branching variable, the 'down-branch' and 'up-branch' LPs are solved and we can inspect the associated dual bounds to measure how good a choice the candidate would be to branch on.</div>
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I can't work out whether cuts are added to these two LPs and, if so, how to prevent them being added. Could someone enlighten me?</div>
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Evidently, if the down and up LPs undergo some separation rounds then we get more useful dual bounds and thus a better idea of the quality of the variable as something to branch on. However, if those separation rounds are expensive, it might be better to skip
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James</div>
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James Cussens</div>
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School of Computer Science, University of Bristol</div>
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<a href="https://jcussens.github.io/">https://jcussens.github.io/</a><br>
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