Briefly describe the main concept of the theory, including major concepts with definitions and major assumptions. 

The main concept of the Social Exchange Theory (SET) is that social relationships are formed and maintained through a process of positive and negative reinforcement. This theory suggests that people will engage in behaviors if they believe it will result in rewards, or be beneficial to their own interests. The major concepts include:

1) Reciprocity – According to SET, giving something of value to another person, such as compliments or gifts, results in positive outcomes for both parties involved. People want to feel appreciated and valued by others, so when they receive something from someone else they are more likely to return the favor and create a relationship with them.

2) Equity – Equity is based on the belief that each individual should receive what he/she puts into an exchange. If both parties contribute equally then there is equity; however, if one party contributes more than the other then there is an inequitable situation which could lead to tension or conflict within the relationship over time.

3) Cost-Benefit Analysis – People tend to evaluate situations before engaging in any behavior, including relationships. They consider whether or not engaging in a certain activity would benefit them more than it costs them (time, money etc.). If it does not appear worth their time/energy then they may choose not to pursue it further.

Major assumptions include:
a) People behave rationally and make decisions based on what brings them maximum benefits while minimizing losses;  b) When forming relationships people assess whether their efforts will be reciprocated; c) Relationships involve mutually beneficial exchanges where both individuals gain something; d) Behavior can be predicted if you consider an individual’s motivations for entering into a relationship as well as their expectations for rewards from it; e) Social interaction involves dynamic processes where power dynamics play out between two individuals depending on who holds a higher value resource at any given time; f ) Individuals have varying levels of tolerance for risk when making decisions about how much they are willing or able to invest emotionally and financially into any particular exchange situation.