protected function _toOptionHash($valueField = 'job_code', $labelField = 'name')
    {
        $res = array();
        foreach ($this as $item) {
            /** @var Aoe_Scheduler_Model_Job $item */
            $res[$item->getDataUsingMethod($valueField)] = $item->getDataUsingMethod($labelField);
        }
        return $res;
    }