Conceptualization is a process of identifying different aspects of a construct, known as dimensions or sub constructs or factors. Dimension precedes items or manifested variables which is directly observable. There are three steps in conceptualization namely, a) specification of constructs, b) different aspects of concepts called dimensions or factors, and c) statements indicating the requested dimensions. Researcher is in need of an operational definition or a measurement system to execute conceputalization. Concept being at the level of thought is a subtle variable that cannot be directly measured. It needs a gross form, which is presented in the form of observational variables, operational definitions played role to bridge the gap between the two levels. Through conceptualization and measurement, researcher establishes the presence of a phenomena or construct in the given context. In other words, concept is a product of mind, and using a measure, the researcher attempts to establish the magnitude of the concepts on the ground. This technique is referred to as “Psychometric techniques”.
what is the role of variable as mediator and moderator in theoretical model?
Baron and Kenny (1987) provides clarity to a model between mediator and moderator variables. Prior to this article, mediator and moderator variables were used interchangeably. Though these are fixed between the independent and dependent variables, however the meaning and role is vastly different. As a mediator, the role of the variable is indirect relation-while as a moderator, the variable presence is to enhance relation between independent (X) and dependent variable (Y). For instance, before introducing mediator, the relationship between X and Y must be confirmed since after the arrival of mediator, generally the relationship between X and Y weakens-only after which the mediator starts to function. This is illustrated as follows:
Baron and Kenny (1987) article gave conceptual clarity between mediator and moderator variables in the model. Prior to this, both mediator and moderator is used interchangeably. Both of these variable placed in between independent and dependent variables but meaning and role is different, As a mediator, role is Indirect relation and as a moderator, enhance relation between independent (X) and dependent variable (Y).
For instance, before introducing mediator, relation between X and Y should be related, but after arrival of mediator, the relation between X and Y should be weaken, then mediator as a role to play. These can be illustrated with example
The above diagram is meant for mediator relation in model, X and Y is independent and dependent variable, here M is mediator c is total relation c’ is direct relation, ab is indirect relation, all the relation can be established using regression analysis, assume c is .60, and ab is .40, and c’ is .20, so c = ab + c’
For moderator, relation between X and Y is enhanced or changed because of introduction of third variable, is known as moderator.
For instance X is education on employee and Y is productivity, relation between X and Y is changed due to M which is level of skill, Low vs. High or it can be numerical measure also, to execute this model, regression can be done between X and Y, M and Y and XM (interaction) on Y, when XM is significantly related with Y, moderator is established.
Though, conceptual clarity is given by Baron and Kenny, further lot of improvisation is made by Sobel, Preacher and Hayes, especially contribution of Hayes is remarkable.