Measurement Scales or Levels

Measurement Scales or Levels

Measurement Scales?

Measurement

Assignment of numbers to Characteristics (variables) of objects, persons or events
Measurement is the foundation of any scientific investigation

Scales: 

Scaling is the process of measuring.

Measurement Scales:

Measurement scales are used to categorize and/or quantify variables.

Nominal Scale:

• It classifies data into mutually exclusive (overlapping), exhausting categories in which no order or ranking can be imposed on the data.
• Assign responses to different categories, having no numerical difference.
• It also called the categorical variable scale, is defined as a scale used for labelling variables into distinct classifications and doesn’t involve a quantitative value or order. 
• It just assign the label to the data by category-wise i.e. Male, Female

Examples:

• Gender: 1=Male, 2=Female (It doesn't matter that what is the number of male or female). 
• What about symptoms of depression from a psychiatric assessment? None=0, Mild=1, Moderate=2, Serve=3
• Where do you live?                1- Suburbs         2- City            3- Town

Nominal scale is often used in research surveys and questionnaires where only variable labels hold significance.

For instance:

• A customer survey asking “Which brand of smartphones do you prefer?” Options: “Apple”- 1, “Samsung”-2, “Oppo”-3, "Infinix"-4.
• Why do you like the above chosen brand for best? Options: “OS”- 1, “Battery”-2, “Design”-3, "Weight"-4.

Ordinal Scale

• It classifies the data into categories that can be ranked; however, precise differences between the rank do not exist.
• Set of categories that are ordered from least to most.

Example:

• Position in a Race, 1st, 2nd, 3rd, 4th and so on...
• Govt jobs Grade BPS-1, BPS-2, BPS-14 etc
• Military Rank
• Grades
• Satisfaction
• Happiness

Interval Scale

• It ranks data and precise differences between units of measure do exist; however, there is no meaningful zero.
• It is defined as a numerical scale where the order of the variables is known as well as the difference between these variables.

Examples:

• Temperature is on the Interval Scale: a difference of 10 degrees between 90 and 100 means the same as 10 degrees between 150 and 160.

Ratio Scale

• It possesses all the characteristics of the interval measurement, and there exists a true zero. .

Examples:

• Weight of a packet of candy.
• Height of a boy,