SCALES OF MEASUREMENT

SCALES OF MEASUREMENT

Definition:
Scales are methods or rules for assigning numbers or labels to variables or observations in order to represent quantities or categories meaningfully in research.

TYPES OF SCALES

1. NOMINAL SCALE

   • Nature: Categorical, with no order or rank.

   • Function: Used for labeling variables without any quantitative value.

   • Examples: Gender (Male/Female), Blood group (A, B, AB, O), Religion.

   • Properties:

     • Classification only

     • No order or distance between categories

     • Cannot perform mathematical operations

2. ORDINAL SCALE

   • Nature: Categorical, with order.

   • Function: Represents categories with a meaningful rank or order, but the intervals between categories are not equal.

   • Examples: Pain severity (Mild, Moderate, Severe), Education level (Primary, Secondary, Higher).

   • Properties:

     • Classification and ordering

     • Unequal intervals

     • No true zero

3. INTERVAL SCALE

   • Nature: Numerical, ordered, with equal intervals but no true zero.

   • Function: Measures variables with consistent intervals between values.

   • Examples: Temperature in Celsius or Fahrenheit, IQ scores.

   • Properties:

     • Classification, ordering, and equal spacing

     • No absolute zero

     • Addition and subtraction possible

4. RATIO SCALE

   • Nature: Numerical, ordered, with equal intervals and a true zero point.

   • Function: Most informative scale; allows all types of mathematical operations.

   • Examples: Height, weight, age, blood pressure.

   • Properties:

     • All properties of interval scale

     • Has an absolute zero

     • All mathematical operations valid

SUMMARY TABLE