The biggest factor in setting the pay levels of for-profit CEOs is corporate profitability, according to the preliminary findings of an investigation by Rep. Elijah E. Cummings, a Maryland Democrat. Cummings examined the compensation of executives at 13 publicly traded for-profits, asking for documentation on whether the companies linked executive pay to the performance of students. Only three companies provided specific references to how they weigh student achievement in setting compensation, according to a statement from Cummings.