A wide variety of psychological theories, research, and revisions have been employed as tools in attempting to select the most valuable human resources for organizations since the early 1900’s. Many of these initial offerings focused almost entirely on the cognitive abilities of the individual; discounting other personality attributes, abilities to function as part of a team, as well as experience and education variables when measuring individual differences (Spearman, 1946). In fact, individuals utilizing these assessments frequently made assumptions that determinants of success could be effectively measured with tests which would positively correlate with performance on other tests. Spearman (1904) identified this concept as the ‘positive manifold’ and reported that it “leads to a large first factor derived from factor analysis, dubbed ‘general intelligence’, or ‘G’ and implied that the particular test used to assess general intelligence is almost irrelevant, as they all intercorrelate highly” under the umbrella of the “principle of indifference indicator”.

“Research linking broad concepts such as cognitive ability and conscientiousness to performance in a wide range of jobs has transformed the practice of personnel selection” during the last several decades (American Psychological Association, 2004). Rather than relying completely on tests that measure only cognitive abilities, recent research paid careful attention to these additional variables and discovered the significant role these intangibles play in determining individual differences and by extension, organizational success. Substantial research by Schmidt and Hunter (1981) supported this new perspective and suggested, “It was also possible to establish clear, simple, and links between broad individual difference variables, such as general cognitive ability or personality traits and success in a wide range of jobs.”

Conscientiousness and general cognitive ability have been identified as two of the most significant individual differences relevant to performance in almost every study conducted on the topic and can account for up to thirty percent of the variance in job performance with even the most complex positions (American Psychological Association, 2004). Rather than viewing each organization as a separate and unique environment with attributes that would not translate to another agency, the aforementioned evolution in thought allowed researchers to accept the possibility that knowledge, skill, and experience gained in one environment might also hold value in another. As evidence of this amplification, relevant research suggests that “general cognitive ability influences job performance largely through its role in the acquisition and use of information about how to do one's job and individuals with higher levels of cognitive ability acquire new information more easily and more quickly, and are able to use that information more effectively” (Schmidt & Hunter, 1998).

In addition to expanding the focus beyond cognitive abilities alone as a performance measure, a number of authors have also cautioned against the blind reliance on data that may lack established evaluative standards. Murphy (1996) for example, suggested that “cognitive ability should be more important in complex jobs, when individuals are new to the job, and when there are changes in the workplace that require workers to learn new ways of performing their jobs”. As with many other researchers, he intimates that other performance measures, tied to a myriad of other traits hold equal, and at times, higher levels of significance. Gottfredson (1991) acknowledges the fact that the "criterion problem is one of the most important, but most difficult problems in personnel research: adding that it has remained one of the most vexing challenges for more than sixty years because there are no empirical standards or ultimate criterion for measuring job performance”. Several authors suggest these challenges may stem from the fact that job performance is behavioral, episodic, evaluative, and multidimensional while representing an "aggregated value" to the organization of performance an individual displays over a standard interval of time, and utilizes varied context within the performance domain (Motowildo, Borman, & Schmit, 1997). Moreover, variations in the perceived goals evaluated by the researcher, focus of the individual being evaluated, individual bias, and reliability of the actual behavior displayed will all maintain an impact in the accuracy of the measured data. 

Correlating performance measures into an effective predictor of success within an organization is a daunting concept for even the most dedicated of researchers, as the relationship between measured performance and relevance to organizational goals is often cloudy at best. Schneider (1996) relates this lack of clarity and connectedness between individual differences and measures of organizational effectiveness as a consequence resulting from researchers disparate measures; focusing on individual level criteria during studies of individual differences and organizational behaviors and organizational productivity with manager studies. Utilizing varying standards requires consideration of these subjects and individuals exclusive of each other, creating these disconnects, as well as a myriad of opportunities to close such gaps and improve organizational effectiveness.

Current research suggests the divide is growing while "exploring the construct of clarity and discriminant validity of work and organization engagement simultaneously, providing insight into how these constructs relate empirically, as well as investigating the nomological network of each" (Farndale, E. Beijer, J.P.M. Van Veldhoven, Kelliher, & Hope-Hailey, 2014). Addressing this disconnect within the organization could aid in narrowing the skewed perspective of the research if individual engagement is increased to more closely resemble the focus attributed to managers and agency leaders. While this individual development within organizations may be a complicated concept that is difficult to introduce and guide, an environment can be created that encourages such action and expansion of vision. Obtaining 'buy in' for such change is critical, as change and development cannot be forced or coerced. "The human capacity for resistance, and subversion is phenomenal when there is no genuine belief and acceptance, as it is much harder, more complicated and more unpredictable to bring about genuine people and context specific development" (Cooper, Flint-Taylor, & Pearn, 2013).

The validity of predictive measures in personnel selection continues to remain in the eye of the beholder and its ongoing popularity with researchers and organizations alike suggests the debate will continue well into the future. Guion and Gottier (1965) suggested caution in generalization of their findings and specifically stressed, “that most studies reviewed were based on purely empirical as opposed to sound theoretical foundations. As such, predicting professional performance related to personality traits that lack a distinct conceptual basis or accepted universal standard maintain significant potential of underestimating the value of these same qualities.

Each of the paragraphs above address the issues associated with placing too much value on cognitive ability while failing to acknowledge the importance that personality and other qualities place in performance and predictive measures. In her 2007 dissertation, Alexander addresses the issue at length and utilizes archival data from more than 3,000 employees at an international technology company focuses on the relationship of one cognitive ability test on long-term job performance as measured by personnel data. In this project, aptitude test scores relevant to both objective and subjective job performance measures were utilized, revealing the fact that while “aptitude test scores are related to long term job performance factors, other factors account for the majority of the variance; the implication is that aptitude should not be the sole consideration when predicting long-term job success” (Alexander, 2007).

Individual differences extend well beyond the concepts Spearman suggested in his early work; even if he eventually abandoned those theories. As anyone who has assembled, interacted with, or served as a member of a team knows without question; cognitive ability is frequently one of the least important facets in determining success of the individual, team, or organization as a whole. 'G' as a concept, or even as a measure of cognitive ability must include a variety of information about the individual and some manner of evaluation of other character traits deemed relevant to the individual or organization performing the research if the data is to hold true value in comparing individual differences. Employers must take a wide variety of material into account when selecting personnel and attempting to predict long term performance based on a narrow scope of evaluative data without an acceptable standard equates with the logic of trusting the same decisions to a Magic 8 Ball.

References

Alexander, S. G. (2007). Predicting long term job performance using a cognitive ability test (Doctoral dissertation, University of North Texas). Retrieved from https://www.talentlens.co.uk/assets/resources/Predicting-long-term-job-performance-using-Cognitive-ability[1].pdf

American Psychological Association. (2004, May 20). American Psychological Association. Retrieved from http://www.apa.org/research/action/who.aspx

Davis, P. (2015, April 29). Why are authors citing older papers? | The Scholarly Kitchen. Retrieved from https://scholarlykitchen.sspnet.org/2015/04/29/why-are-authors-citing-older-papers/

Gottfredson, L. S. (1991). The evaluation of alternative measures of job performance. National Academy of Science Press. Retrieved from http://www.udel.edu/educ/gottfredson/reprints/1991alternativemeasures.pdf

Guion, R. M. (n.d.). Robert M Guion autobiography. Retrieved from http://www.siop.org/presidents/Guion.aspx

Guion, R. M., & Gottier, R. F. (1965). Validity Of personality measures In personnel selection. Personnel Psychology, 18(2), 135-164. doi:10.1111/j.1744-6570.1965.tb00273.x

Motowildo, S. J., Borman, W. C., & Schmit, M. J. (1997). A Theory of Individual Differences in Task and Contextual Performance. Human Performance, 10(2), 71-83. doi:10.1207/s15327043hup1002_1

Spearman, C. (1904). "General Intelligence," Objectively Determined and Measured. The American Journal of Psychology, 15(2), 201. doi:10.2307/1412107

Spearman, C. E. (1946). Charles Edward Spearman. British Journal of Psychology. General section, 36(2), 54-54. doi:10.1111/j.2044-8295.1946.tb01106.x

Whitbourne, S. K. (2014, April 1). The secret to revealing your secrets | Psychology Today. Retrieved from https://www.psychologytoday.com/blog/fulfillment-any-age/201404/the-secret-revealing-your-secrets