Abstract

Personality plays a key role in organizational behaviour because the way that people think, feel, and behave affects many aspects of the workplace. In the workplace, personality also affects such things as motivation, leadership, performance, and work effectiveness. The more those people understand how personality in organizational behaviour works, the better equipped they are to be effective and accomplish their goals.  The present study was designed to investigate the relationship between personality traits and work effectiveness in a sample of 1,026 employees in electricity generating authority of Thailand (EGAT) selected by stratified random sampling method. Using the two tools, the scale which measures the personality traits which based on the Big Five personality traits suggested by Goldberg’s five-dimension personality model (1990) and Costa and McCrae’s NEO personality inventory (1992) and the scale which measures the work effectiveness which confined to the basic assumption of Fred E. Fiedler’s contingency theory (1997), the data was obtained. The descriptive statistics were used for data analysis i.e. percentage (%), mean ( ), and standard deviation (S.D.).  The Analysis of Variance was used to test the difference between mean scores of personality traits and the work effectiveness rated by EGAT employees belonging to different groups of age, level education, and work experience. t-test (independent) was used to test the difference between mean scores of the personality traits and the work effectiveness rated by male and female EGAT employees. In order to find out the effect of personality traits on the work effectiveness, the Analysis of Variance was used. The Pearson Product Moment Correlation Co-efficient ( ) was employed for testing the relationship between personality traits and work effectiveness of EGAT employees.  Through careful analysis, it was found that personality traits and work effectiveness of EGAT employees was at moderate level.  Sex, age, level of education, and work experience did effect on the total mean scores of personality traits. Age, level of education did effect on the total mean scores of work effectiveness of EGAT employees whereas sex did not effect on the total mean score of work effectiveness.  Personality trait did effect on the mean scores of work effectiveness.   There was the significant positive relationship between personality traits and work effectiveness of EGAT employees.