stats/src/main/java/io/airlift/stats/QuantileDigest.java
private double computeMaxPathWeight(int node)
    {
        if (node == -1 || levels[node] == 0) {
            return 0;
        }

        double leftMaxWeight = computeMaxPathWeight(lefts[node]);
        double rightMaxWeight = computeMaxPathWeight(rights[node]);

        return Math.max(leftMaxWeight, rightMaxWeight) + counts[node];
    }
private double computeMaxPathWeight(int node)
    {
        if (node == -1 || levels[node] == 0) {
            return 0;
        }

        double leftMaxWeight = computeMaxPathWeight(lefts[node]);
        double rightMaxWeight = computeMaxPathWeight(rights[node]);

        return Math.max(leftMaxWeight, rightMaxWeight) + counts[node];
    }
Computes the max "weight" of any path starting at node and ending at a leaf in the
hypothetical complete tree. The weight is the sum of counts in the ancestors of a given node