X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=c7d2efd40da46bb6189e834fea0bee051ae2f182;hp=4aeadc28a7802c506309091f8371ad92715d7bf9;hb=5f426d8667feda65eaf1eca699f629d31e170d43;hpb=9a063fc3cbc8f522215392db232eeb0e04e71b2c

diff --git a/src/search.cpp b/src/search.cpp
index 4aeadc28..c7d2efd4 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -520,7 +520,7 @@ void Thread::search() {
               totBestMoveChanges += th->bestMoveChanges;
               th->bestMoveChanges = 0;
           }
-          double bestMoveInstability = 1 + totBestMoveChanges / Threads.size();
+          double bestMoveInstability = 1 + 2 * totBestMoveChanges / Threads.size();
 
           double totalTime = rootMoves.size() == 1 ? 0 :
                              Time.optimum() * fallingEval * reduction * bestMoveInstability;
@@ -654,9 +654,7 @@ namespace {
     // starts with statScore = 0. Later grandchildren start with the last calculated
     // statScore of the previous grandchild. This influences the reduction rules in
     // LMR which are based on the statScore of parent position.
-    if (rootNode)
-        (ss+4)->statScore = 0;
-    else
+    if (!rootNode)
         (ss+2)->statScore = 0;
 
     // Step 4. Transposition table lookup. We don't want the score of a partial