What is a variable in social research? What are their different types? Elaborate. (Answer in 150 words)

- What is a variable in social research? What are their different types? Elaborate. (Answer in 150 words)
Introduction
A variable is what makes a social phenomenon countable and comparable.

Body

1. What a variable is: Any characteristic taking more than one value across the units studied — religion, income, caste. A constant explains nothing: variation is the condition of explanation. Defining one means fixing its categories and the rule assigning cases to them.

2. The types, set against one another: By role: the independent variable is the assumed cause, the dependent the effect, the intervening one transmits it, and extraneous variables must be controlled or they manufacture spurious relations — Durkheim's Suicide runs religion as independent, the suicide rate as dependent, social integration as intervening. By form: discrete or continuous. By level of measurement, following Stevens: nominal, ordinal, interval and ratio, each permitting more arithmetic than the last.

3. Why the distinctions decide a design: They fix the statistics and the controls: nominal data yield proportions, not means, and an uncontrolled extraneous variable turns association into false causation — what Lazarsfeld's elaboration was built to expose.

Conclusion
Weak findings usually begin in badly specified variables, not bad arithmetic.