Editing Construct validity (section)

=== Nomological network ===
{{Main|nomological network}}
Lee Cronbach and Paul Meehl (1955)<ref name="Cronbach55"/> proposed that the development of a nomological net was essential to the measurement of a test's construct validity. A [[nomological network]] defines a construct by illustrating its relation to other constructs and behaviors. It is a representation of the concepts (constructs) of interest in a study, their observable manifestations, and the interrelationship among them. It examines whether the relationships between similar construct are considered with relationships between the observed measures of the constructs. A thorough observation of constructs relationships to each other it can generate new constructs. For example, [[intelligence]] and [[working memory]] are considered highly related constructs. Through the observation of their underlying components psychologists developed new theoretical constructs such as: controlled attention<ref>Engle, R. W., Kane, M. J., & Tuholski, S. W. (1999). Individual differences in working memory capacity and what they tell us about controlled attention, general fluid intelligence, and functions of the prefrontal cortex. In A. Miyake, & P. Shah (Eds.), Models of working memory (pp. 102−134). Cambridge: Cambridge University Press.</ref> and short term loading.<ref>{{cite journal |author1=Ackerman P. L. |author2=Beier M. E. |author3=Boyle M. O. | year = 2002 | title = Individual differences in working memory within a nomological network of cognitive and perceptual speed abilities | journal = Journal of Experimental Psychology: General | volume = 131 | issue = 4| pages = 567–589 | doi=10.1037/0096-3445.131.4.567|pmid=12500864 }}</ref> Creating a nomological net can also make the observation and measurement of existing constructs more efficient by pinpointing errors.<ref name="Cronbach55"/> Researchers have found that studying the bumps on the human skull ([[phrenology]]) are not indicators of intelligence, but volume of the brain is. Removing the theory of phrenology from the nomological net of intelligence and adding the theory of brain mass evolution, constructs of intelligence are made more efficient and more powerful. The weaving of all of these interrelated concepts and their observable traits creates a "net" that supports their theoretical concept. For example, in the nomological network for academic achievement, we would expect observable traits of academic achievement (i.e. GPA, SAT, and ACT scores) to relate to the observable traits for studiousness (hours spent studying, attentiveness in class, detail of notes). If they do not then there is a problem with measurement (of [[academic achievement]] or studiousness), or with the purported theory of achievement. If they are indicators of one another then the nomological network, and therefore the constructed theory, of academic achievement is strengthened. Although the nomological network proposed a theory of how to strengthen constructs, it doesn't tell us how we can assess the construct validity in a study.