Levels of Measurement of Data

Measurement, it is assigning a numerical value to a variable. For example, the reading of a thermometer is 35ºC, or when examining bulbs, 3 are defective.

a.Nominal Data (Classificatory Scale) is the weakest level of measurement where numbers or symbols are used simply for categorizing subjects into different groups.Examples: Gender ->M= Male, F = Female

Marital Status -> 1 = Single, 2= Married,

3=Widowed, 4 = Separated

b. Ordinal Data (Ranking Scale) contains properties of the nominal level and in addition, the numbers assigned to categories of any variable may be ranked or ordered in some low- to high manner. This type of data, numbers represents “greater than” or “less than” measurements.

Examples: -Year Level -> 1=1st yr, 2= 2nd yr,3 =3rd yr,4 = 4th yr- Ratings -> 1= Poor, 2= Fair, 3= Good, 4 = Excellent

c.Interval Data has the properties of the ordinal and in addition, the distances between any two numbers on the scale are known sizes, interval scale must have a common and constant unit of measurement ( unit of measurement is arbitrary and there is NO ZERO point).

Examples: -IQ Level-Temperature

d. Ratio contains all the properties of the interval level and in addition, has a TRUE ZERO pointExamples: -Scores in a certain test

-Age ( in years )-Election vote-Weight, height, length, area,

volume, density, velocity, money, etc.