What kind of data does a ratio scale involve in research?

A ratio scale involves data that has fixed intervals and a true zero point, making it the highest level of measurement in research. This means that not only can you measure the distance between values with consistent intervals, but you can also say that one value is a multiple of another, which indicates meaningful relationships between the data points. The presence of a true zero allows researchers to make definitive statements regarding the absence of the quantity being measured, such as weight or height.

For example, if a person's weight is zero, it means they have no weight at all, which is a meaningful point of reference. This allows for a full range of mathematical operations to be performed on the data, such as addition, subtraction, multiplication, and division. Ratio scales are commonly used in fields such as psychology, health sciences, and social sciences when precise measurements are essential.