yes, therapy helps!
Intelligence: the G Factor and the Bifactorial Spearman Theory

Intelligence: the G Factor and the Bifactorial Spearman Theory

June 12, 2024

The study of intelligence is one of the subjects that attracts the most interest, and it is easy to suppose the reasons why this is so. On the one hand, ability to adapt to varied situations it is something that is considered a lot in an increasingly demanding job market and that always seeks maximum productivity on the part of the worker.

On the other hand, at a much more subjective level, intelligence has become a defining issue of one's identity and that affects self-image and self-esteem. Now, intelligence may seem too abstract and general a concept to be graspable by science. How is this problem addressed from the psychometry ?


The two factors of intelligence

In the study of intelligence there are different paradigms, such as, for example, fluid intelligence and crystallized intelligence. However, it is the Bifactorial Theory of the English psychologist Charles Spearman (1863 - 1945) the one that perhaps has had more notoriety historically.

Spearman observed that the scores that school children had in each of the subjects showed a direct relationship, so that a student who scores very well in a subject will also tend to score well in the rest of the subjects. From this fact, he devised an explanatory model on intelligence apt to be the starting point for the measurement of I.Q (CI ). This explanatory model is called Bifactorial Intelligence Theory .


According to this theory, intelligence, which is the theoretical construct that is measured by tests in the form of IC, has two factors:

Factor G

A general factor of intelligence , the call Factor G, which is the essential foundation of intelligent behavior in any particular situation it may be.

S Factors

A series of specific factors, which can be understood as skills and aptitudes that are present only in certain areas of life and whose results can not be generalizable to other domains.

A good example to explain the Bifactor Theory can be found in the case of Brain Training videogames. These games seem to be designed to improve our G Factor through the game. That is, a few hours of play per week would have to produce the result in the person who plays them with greater intelligence in any situation. However, it seems that they only act on the S Factors: one sees an increase in their ability to play, but this improvement is not generalized to other areas, it is a specific learning whose results do not go beyond the video game itself .


From the abstract to the concrete data

We can agree with Spearman that if something characterizes intelligence is its abstract nature . In the study of intelligence there is the paradox of trying to explain something that is defined by changing all the time in its adaptation to the different problems that we live: our ability to successfully solve the infinitely varied series of problems with scarce resources (among them , time). In this sense, it seems necessary to account for something similar to Factor G.

Now, by including an abstract concept as the general factor of intelligence, this theoretical model becomes impractical if it is not based on the concrete data, on what we find empirically through IQ measurements. That's why, in addition to coining the term Factor G, Spearman devised a strategy in parallel to arrive empirically at specific values ​​that defined it. In this way, at the time of operationalize concepts to build intelligences measurement tools (the IQ test), the Factor G it is defined as the representation of the variance common to all the cognitive tasks that are measured by the test. This internal structure of the relationships between the data is found through the use of factor analysis.

Speraman thought that intelligence consisted in knowing how to perform a series of tasks and that the smartest people knew how to do all the tasks well. The different tasks proposed in the IQ test could be organized into three groups (visual, numerical and verbal), but all of them were correlated. This last factor, resulting from the study of these correlations, would be the significant one.

Therefore, the G Factor that is reflected by the tests is actually a quantifiable measure that can only be found by statistical operations from the raw data collected in each of the tasks of the test. In opposition to calls observable variables, the Factor G Spearman shows us a matrix of correlations between variables that can only be found using the statistical technique.That is, it makes visible the structure of relationships between different variables to create a general value that was hidden, the value of the Factor G.

The G Factor, today

Today each intelligence test can be based on different theoretical frameworks and conceptions of intelligence , precisely because of the abstract of this last concept. However, it is common that these measurement tools include scores on specific areas of competence (language, spatial intelligence, etc.) at various levels of abstraction, and that they also offer a G Factor as a value that summarizes the general intelligence of the individual. It can be considered that many intelligence measurement modalities are direct descendants of Spearman's theory.

The IQ tests have the pretension to measure intelligence in a psychometric way depending on the genetic variables or "g". It is an indicator that is usually used in academic settings or to detect possible developmental disorders (such as maturational delays) and is also used to establish correlation relationships between the environment and the genetic components of intelligence: the Factor G has been correlated with life expectancy, the possibility of finding a job and other relevant constructs .

Criticism and discussion

The criticisms that can be made are basically two. The first is that the general intelligence factor seems to be affected by the cultural bias : the economic position, educational level and geographical distribution of housing seems to affect the results of intelligence, and this is a question that can not be explained only by genetic variation. The second is that, however practical it may be, the G Factor is insensitive to the different forms of manifestation of intelligence , the particularities that make each person develop intelligent behavior in their own way (something that has tried to correct itself from Howard Gardner's multiple intelligences model, for example).

Be that as it may, it is clear that the G Factor is a very interesting concept in the face of research in psychology and social sciences.


Spearman (June 2024).


Similar Articles