A variable is a symbol of an event, act, characteristics, trait, or attributes that can be measured and. assigned categorical values. In other words, any signal or figure, or symbol which represents the quality, characters, and facts is known as a variable. The value of a variable differs from one activity to the next activity. Value of variable differs to some person or product in different time periods. Motivation, government policy, satisfaction are some examples of variables. Motivation level towards work differs as per members of the organization. It may be very high and very low in different people. Thus, motivation differs as per person, so it is a variable. Generally, numerical values are allotted to the variables on the basis of their features that help to keep a record and analyze them.
Some variables Can be Classified only into two groups, like men and women, employed and unemployed. Such variables are provided 0 and 1 symbols. Some variables may be classified into various groups. For example, employees are highly absent, normally absent, and less absent in the organization. Regular values like 1, 2, 3, are given to these variables. Such variables are used in social science research.
According to F.N. Kerlinger, “A variable is a symbol to which numerals or values are assigned.“
According to P.V. Young, “A variable is any quantity or characteristics which may pose different numerical values or categories.“
From the analysis of the above definition, it can be said that measurement is a process of assigning numbers, symbols, or values that represents the characteristics of the variables.
Types of Variables
Variables can be classified into the following groups on the basis of their use in research:
1. Independent variables:
A variable that influences the dependent variable in a positive or negative way is known as an independent variable. Such variables do not change due to changes in other variables but it leads to change independent variables. If the independent variable is changed by one unit then the dependent variable will be changed to some degree. For example, there is a theory that employee stress reduces the performance of employees. It means if employee stress decreases, performance increases and if employee stress increases, performance decreases. In this example, performance is based on stress but the change in performance does not change in stress. So, employee stress is an independent variable.
2. Dependent variables:
Variables, which are affected by the change in independent variables, are known as the dependent variables. The dependent variable is the variable of primary interest to researchers. The researcher’s goal is to explain or predict the variability in the dependent variable. By the analysis of the dependent variable, the researcher finds the solution to the problem. For example, new product development increases sales. Here, a sale is a dependent variable because a sale is influenced by product development.
Following figures shows the independent and dependent variable:
3. Moderating variables:
A variable that affects the nature Of the relationship between the independent and dependent variable is known as moderating variable. The presence of moderating variables (third variable) modifies the originally expected relationship between the independent and the dependent variables. For example, the effect of varying levels of stress in different employees influences the relationship between the management style and retention. If there is more stress, employees may leave the job quickly. Gender and age are often moderating variables because stress-absorbing capacity depends on the age and gender of the people.
The following figure shows the impact of moderating variable:
4. Intervening variables:
An intervening variable is one that surfaces between the time the independent variable operates to influence the dependent variable and its impact on the dependent variable. The intervening variable surfaces as a function of the independent variable/ variables operating in any situation and helps to conceptualize and explain the influence of the independent variable on the dependent variable. Existence of such variable is essential to show the relationship between dependent and independent variables. For example, generally, it is assumed that proper HR practices enhance performance of an organization but favourable environment is essential to exist such relationship between HR practices and organizational performance. Thus, environment is intervening variable.