public List getOutliers(int row, int column);

    /**
     * Returns a list of outlier values for an item.  The list may be empty, 
     * but should never be <code>null</code>.
     *
     * @param rowKey  the row key.
     * @param columnKey  the columnKey.
     *
     * @return A list of outlier values for an item.
     */
    public List getOutliers(Comparable rowKey, Comparable columnKey);