Researchers Who Introduced General Intelligence Or "G" Factor

Spearman (1904) was one of the first researchers to introduce general intelligence, commonly known as “g” factor. Spearman (1904) had thought that the “g” factor was the reason behind performance on mental ability tests. Spearman (1904) had also claimed that individuals who perform well in a certain area also excelled in other areas. For example, an individual who performed well on a mathematical test would also perform well on other tests.

After the work of Spearman (1904), came Thurstone (1934), who had though that Spearmans (1904) theory was limited due to the fact that the variables only had “g” in common. Thurstone (1934) implied hat intelligence was sourced from seven abilities as appose to the abilities resulting from factor “g”, as Spearman (1904) had imposed. The seven abilities that Thurstone (1934) introduced are; verbal comprehension, word fluency, number facility, spatial visualization, associative memory, perceptual speed and reasoning. These mental abilities, explained by Thurstone (1934) are primary mental abilities which are needed in order for a person to be successful in their environment.

However another researcher, Cattell (1971) agrees with the work of Spearman (1904) with regards there being a “g” factor and disagreed with the work of Thurstone (1934). This is because Cattell (1971) argued that the intercorrelations imply that there is an overall “g” factor. Cattell’s (1971) theory is slightly different to Spearman’s (1904) theory, as Cattell (1971) proposes that “g” can be achieved through two factors; crystallised intelligence (Gc) and fluid intelligence (Gf). Gc is ones skills and knowledge that has been attained over a long period of time. Gf is he reasoning ability an individual has, which is natural and grows with the individual into adulthood.

General Mental Ability tests (GMA) are used in job interviews to measure an individual’s skills and personality. These tests are seen as strong predictors of how new recruits will perform on the job in most working environments. GMA tests tend to be more accurate in predicting job performance with job roles that are more complex. The connection between GMA and job performance is stronger when the employee has a lot of experience in the field. If one new recruit was to learn the role faster compared to another employee with the same experience, there is an increased chance that the person who learned faster will perform better. Therefore it is essential to test the candidate’s skills even though they may have previous experience.

Although GMA is seen as a strong indicator of job performance, there is research that shows the correlation between GMA and job performance is weakened overtime (Keil & Cortina 2001). This is due to the fact that when new recruits initially start, they are more focused on being able to learn the basic tasks and duties that their role entails. As they gain more experience and understanding of their job, the need for job specific development is reduced. Therefore, they are less dependent upon GMA in order to perform their roll and instead they are reliant upon their individual characteristics, such as personality, to meet the requirements of their position. However, this does not mean that GMA will become irrelevant; there may be more significant factors which will have more of an impact on performance as time progresses and individuals gain more experience.

Furthermore, the status of an individual’s employment, responsibilities and duties will have an effect on the degree to which GMA will influence performance. Especially, the extent to which the duties and responsibilities are similar over a period of time, can have an influence to the extent to which performance becomes repetitive and can influence the degree to which GMA and comparable abilities are be used to predict performance (Ackerman 1986). Repetitive tasks can be described as a task that becomes second nature to an employee which does not require much effort, with an increased chance of achieving high levels of accuracy. On the other hand, incoherent tasks can be described as tasks employees are constantly learning and developing themselves.

If a job requires an employee to be continuously learning, then GMA will be a stable predictor of job performance, as the employee is constantly developing. In contrast, if the job entails repetitive tasks, it is possible that GMA will be more accurate towards the early stages of the employee and can decrease in significance as the individual will gain the skills that is required to perform their role. Thus, the validity of prediction with regards to GMA will decrease in jobs that involve repetitive tasks, leading to employees other characteristics and abilities to better predict their performance.

Then GMA will likely be more relevant at the earlier stages of employment but decrease in importance as individuals acquire the knowledge and skills required to perform the job duties.