Verhältnisskalenwerte
Verhältnisskalenwerte, also known as ratio scale values, represent a level of measurement where not only are the distances between values equal and meaningful, but there is also a true, absolute zero point. This zero point indicates the complete absence of the measured quantity. Examples of verhältnisskalenwerte include measurements like height, weight, age, temperature in Kelvin, income, and time elapsed. Because of the absolute zero, mathematical operations such as multiplication and division are permissible and meaningful. For instance, if one person is 2 meters tall and another is 1 meter tall, the first person is twice as tall as the second. This kind of comparison is not possible with nominal or ordinal scales, and can be misleading with interval scales. The absolute zero allows for statements about proportions and ratios. Statistical analysis techniques appropriate for ratio scales are more powerful and diverse than those used for lower levels of measurement, including geometric means and coefficients of variation.