Furthermore, one of the arguments often brought against theories of job satisfaction is that they take little account of differences between people and neglect the personal correlate factors of job satisfaction. Hagedorn (1994) examined the satisfaction of academic staff using various variables, including salary, perceived support from colleagues, satisfaction with administration, enjoyment of student interaction and perceived stress levels. Oshagbemi (2003) investigated a research on personal correlates of overall job satisfaction show empirical evidence from UK universities, which explore the relationships between age, gender, rank, and length of service with job satisfaction. The results of research show that the rank of an academic staff plays a significant and positively role of the level of the overall teacher job satisfaction. And the length of service academic staff who worked in higher education is also connected with individual’s overall job satisfaction but in a negative way. The interaction effect of rank and gender affects the level of overall job satisfaction of university teachers extensively. More specificallyï¼Œ it means that gender affects the job satisfaction of university teachers within certain ranks. Lastly, a person’s ability is another individual variable that has been shown to be correlated with job satisfaction.