job satisfaction in light of evidence that job satisfaction tends to be stable over time and across careers and jobs. Research also indicates that identical twins raised apart have similar levels of job satisfaction. A significant model that narrowed the scope of the dispositional approach was the Core Self-evaluations Model, proposed by Timothy A. Judge, Edwin A. Locke, and Cathy C. Durham in 1997. Judge et al. argued that there are four core self-evaluations that determine one's disposition towards job satisfaction: self-esteem, general self-efficacy, locus of control, and neuroticism. This model states that higher levels of self-esteem (the value one places on oneself) and general self-efficacy (the belief in one's own competence) lead to higher work satisfaction. Having an internal locus of control (believing one has control over one's own life, as opposed to outside forces having control) leads to higher job satisfaction. Finally, lower levels of neuroticism lead to higher job satisfaction. Equity theory Equity Theory shows how a person views fairness in regard to social relationships such as with an employer. A person identifies the amount of input (things gained) from a relationship compared to the output (things given) to produce an input/output ratio. They then compare this ratio to the ratio of other people in deciding whether they have an equitable relationship. Equity Theory suggests that if an individual thinks there is an inequality between two social groups or individuals, the person is likely to be distressed because the ratio between the input and the output are not equal. For example, consider two employees who work the same job and receive the same pay and benefits. If one individual gets a pay raise for doing the same work as the other, then the less benefited individual will become distressed in the workplace. If, on the other hand, both individuals get pay raises and new responsibilities, then the feeling of equity will be maintained. Other psychologists have extended the equity theory, suggesting three behavioral response patterns to situations of perceived equity or inequity. These three types are benevolent, equity sensitive, and entitled. The level by each type affects motivation, job satisfaction, and job performance. Benevolent-Satisfied when they are under-rewarded compared with co-workers Equity sensitive-Believe everyone should be fairly rewarded Entitled-People believe that everything they receive is their just due Discrepancy theory The concept of discrepancy theory is to explain the ultimate source of anxiety and dejection. An individual