Organizational behavior psychologists study how employees compare their own ratios of outcomes to inputs with relevant others. When the ratios are equal, employees feel equitable and fair, but when unequal, underrewarded employees feel anger and overrewarded employees feel guilt. To reduce this tension and inequity, employees may change their own inputs or outcomes, distort perceptions of self or others, change the reference person used for comparison, or quit their job. The type of pay system can also impact how employees address inequity - those paid by time or quality may over or underproduce depending on their perception of being over or underrewarded.