Nominal Scale: Measurement by restricting data together under specific classifications or groups: by gender, geographically, by weight, etc.; allows for the determination of mode or percentage values to a whole unit. Ordinal Scale: Measurement in terms of value symbols: greater than, higher than, smaller than, etc., in comparison of data; allows for the determination of rank order and correlation. Interval Scale: A rating measurement scale characterized by equal units of measurement and having its zero point established arbitrarily; allows for the determination of the mean, standard deviation, and product moment correlation. Ratio Scale: A type of interval scale measuring in terms of equal intervals and an absolute zero point of origin; allows for the determination of percentage variation and geometric mean.

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