¶ … measurement level has a basic property and all the properties of the levels below. At the basic levels of measurement there are nominal levels of measurement where the assigned numerical value simply identifies an observation but there is no quantitative relationship in the data. A test using nominal levels of measurement could be one asking simple yes/no questions regarding whether a person experiences certain symptoms (Huck, 2012). The second level of measurement involves ordinal levels of measurement where the assigned numerical value identifies and establishes an order from highest to lowest, such as in a test of the severity of symptoms from low, to medium, to high (Huck, 2012). At these levels of measurement the researcher's ability to make inferences regarding the data is limited, because distance between points is not uniform. At the interval level of measurement the researcher assigns...

The values associated with the observations on interval level scale are a truly quantitative value and therefore interval level scales permit the researcher to use arithmetic operations in analyzing the data; however, interval levels lack a true zero point. The highest level of measurement is the ratio level scale where there is a true zero point and allows for ratio-level comparisons such as a measurement of reaction time where 20 ms is twice as much as 10 ms (Huck, 2012).
Measures of central tendency describe how scores tend to bunch in the distribution (Huck, 2012).…