the process of assigning numerals to variables to represent quantities of characteristics according to certain rules
continuous variable
A quantitative variable that can theoretically take on values along a continuum within a defined range
discrete variables
a variable that can only be measures in seperate units and that cannot be measures in intervals of less than 1
dichotomous variable
a nominal variable having only 2 categories, such as yes/no and male/female; a binomial variable
precision
exactness of a number; used to indicate the number of decimal places to which a number is taken
ex. 1.4738 is a number greater in precision then 1.47
constructs
types of abstract variables; measurement of constructs are based on expectations of a how a person who possesses the specified trait would behave, look, or feel in certain situations
scales or scales of measurement (level of measurement)
the precision of a scale based on how a characteristic is measured; nominal, ordinal, interval, and ratio levels
nominal scale or classificatory scale
level of measurement for classification variables; assignment of "values" based on mutually exclusive and exhaustive categories with no inherent rank order
ordinal scale
level of measurement in which scores are ranks
interval scale
level of measurement in which values have equal intervals, but no true zero point
ratio scale
the highest level of measurement, in which there are equal intervals between score units and a true zero point