diff --git a/hyracks/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/partition/FieldHashPartitionComputerFamily.java b/hyracks/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/partition/FieldHashPartitionComputerFamily.java
index 51645c4..ec3c2be 100644
--- a/hyracks/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/partition/FieldHashPartitionComputerFamily.java
+++ b/hyracks/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/partition/FieldHashPartitionComputerFamily.java
@@ -52,10 +52,10 @@
                     h += fh;
                 }
                 if (h < 0) {
-                    h = -h;
+                    h = -(h+1);
                 }
                 return h % nParts;
             }
         };
     }
-}
\ No newline at end of file
+}