nomological network

{{short description|Representation of concepts and relationships between concepts}}

A nomological network (or nomological net{{Citation|last1=Preckel|first1=Franzis|title=Nomological Nets|date=2017|encyclopedia=Encyclopedia of Personality and Individual Differences|pages=1–4|editor-last=Zeigler-Hill|editor-first=Virgil|publisher=Springer International Publishing|language=en|doi=10.1007/978-3-319-28099-8_1334-1|isbn=9783319280998|last2=Brunner|first2=Martin|editor2-last=Shackelford|editor2-first=Todd K.}}) is a representation of the concepts (constructs) of interest in a study, their observable manifestations, and the interrelationships between these. The term "nomological" derives from the Greek, meaning "lawful", or in philosophy of science terms, "law-like". It was Cronbach and Meehl's view of construct validity that in order to provide evidence that a measure has construct validity, a nomological network must be developed for its measure. {{cite journal |last1=Cronbach |first1=L.J. |last2= Meehl|first2= P.E. |year= 1955 |title = Construct validity in psychological tests |journal=Psychological Bulletin |volume=52 |pages=281–302 |doi=10.1037/h0040957 |pmid=13245896 |issue=4|hdl=11299/184279 |s2cid=5312179 |hdl-access=free }}

The necessary elements of a nomological network are:

• At least two constructs;
• One or more theoretical propositions, specifying linkages between constructs, for example: "As age increases, memory loss increases".
• Correspondence rules, allowing each construct to be measured empirically. Such a rule is said to "operationalize" the construct, as for example in the operationalization: "Age" is measured by asking "how old are you?"
• Empirical linkages represent hypotheses before data collection, empirical generalizations after data collection.

Validity evidence based on nomological validity is a general form of construct validity. It is the degree to which a construct behaves as it should within a system of related constructs (the nomological network). {{cite journal |last1=Liu |first1=Liping |last2= Li |first2= Chan |last3= Zhu |first3=Dan |year= 2012 |title = A New Approach to Testing Nomological Validity and Its Application to a Second-Order Measurement Model of Trust |journal=Journal of the Association for Information Systems |volume=13 |issue=12 |pages=950–975 |doi=10.17705/1jais.00320 |doi-access=free }}

Nomological networks are used in theory development and use a modernist{{clarify|date=December 2020}} approach.Alavi, M, Archibald, M., McMaster, R. Lopez, V. and Cleary, M. (2018) Aligning theory and methodology in mixed methods Research: Before Design Theoretical Placement International Journal of Social Research Methodology 21:5, 527-540