A ratio scale is a type of variable measurement scale that is quantitative in nature and is the highest level of scale. It allows researchers to compare intervals or differences and has most of the characteristics of nominal, ordinal, and interval scales. The key features of a ratio scale include:

• True Zero: A ratio scale has a true zero, which means that the zero point on the scale represents the absence of the variable being measured. This makes it possible to describe the amount of magnitude involved.

• Order and Equal Distance: A ratio scale describes the order and equal distance between two values. This means that the variables can be added, subtracted, multiplied, and divided, and there are no negative values involved.

• Examples: Common examples of variables that can be measured on a ratio scale include height, weight, age, money, duration, and mass. In market research, ratio scales are useful for analyzing concepts like sales numbers, market share, customer data, and pricing.

Ratio scales are the most informative scale as they tend to tell about the order and number of the object between the values of the scale. They provide unique possibilities for statistical analysis plan, and all forms of statistical analysis can be applied to them.