Which concept involves beliefs about fair allocation of rewards?

The concept that involves beliefs about fair allocation of rewards is indeed Equity Theory. This theory focuses on how individuals assess the fairness of their outcome-to-input ratios in relation to others. When people perceive inequities in the distribution of rewards, such as pay or recognition, they may feel dissatisfied and motivated to restore equity, whether through changing their efforts, altering their perceptions, or even leaving the situation.

Equity Theory posits that fairness perceptions are crucial in maintaining motivation in workplaces and social settings. For instance, if an employee believes they are putting in as much effort as a coworker but receiving fewer rewards, they may become demotivated and disengaged.

The other theories mentioned, while related to motivation and workplace behavior, do not directly focus on the fairness of reward allocation. Expectancy Theory deals with the expectation that effort will lead to performance and consequential rewards, but does not specifically address fairness. Justice Theory encompasses broader principles of fairness and ethics in social interactions, but it is not as narrowly focused on the employee's perception of reward allocation as Equity Theory is. Motivation Theory is a general term that includes various theories related to motivation but lacks the specific focus on fairness in distribution that Equity Theory provides.