SELECT t1.[NAME] as CHIEF_NAME
FROM EMPLOYEE As t1 JOIN (
SELECT CHIEF_ID, AVG(SALARY) AS AVG_EMPLOYEE_SALARY
FROM EMPLOYEE
WHERE CHIEF_ID IS NOT NULL
GROUP BY CHIEF_ID) AS t2 ON t1.ID = t2.CHIEF_ID
WHERE t1.SALARY > (t2.AVG_EMPLOYEE_SALARY * 2)