code: private boolean existsOutdatedEntryOnPath(Node node) {
      	if (node == root){
      		node.makeOlder(timestamp, negLambda);
      		return node.getIrrelevantEntry(this.weightThreshold)!=null;
      	}
      	do{
      		node = node.getEntries()[0].getParentEntry().getNode();
      		node.makeOlder(timestamp, negLambda);
      		for (Entry e : node.getEntries()){
      			e.recalculateData();
      		}
      		if (node.numFreeEntries()>0)
      			return true;
      		if (node.getIrrelevantEntry(this.weightThreshold)!=null)
      			return true;
      	}while(node.getEntries()[0].getParentEntry()!=null);
  		return false;
  	}
docs: This method checks if there is an outdated (or empty) entry on the path from node to root.
  It updates the weights of nodes on path and then checks if it is outdated.
  @param node
  @return true if an outdated/empty entry exists on the path