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What is Nominal Data?
Learn nominal data, its characteristics, applications in business, healthcare, and social sciences, and how it helps in classification and analysis
What is Ordinal Data?
Discover what ordinal data is, its characteristics, business applications, healthcare, and education, and how it helps in ranking and preference analysis
Marco Giardina
Feb 3, 2025
Ordinal data is a type of categorical data that has a meaningful order or ranking but lacks a fixed interval between values.
Unlike nominal data, which only categorizes variables without sequence, ordinal data allows for a relative comparison between values without specifying exact differences.
Ordinal data is commonly used in surveys, social sciences, business analytics, and customer feedback analysis to classify information based on ranking or levels.
Key Characteristics of Ordinal Data
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Ordered Categories – Data is arranged in a meaningful sequence.
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No Fixed Interval – Differences between values are not necessarily equal.
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Qualitative but Ranked – Can be descriptive but follows an order.
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Limited Arithmetic Operations – Cannot perform mathematical calculations like addition or subtraction.
Examples of Ordinal Data
Ordinal data is widely used across various industries and research fields:
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Customer Satisfaction Surveys – Rating levels (Poor, Fair, Good, Excellent).
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Education – Letter grades (A, B, C, D, F) indicating performance.
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Job Performance Reviews – Rankings such as "Needs Improvement," "Meets Expectations," "Exceeds Expectations."
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Socioeconomic Status – Lower, Middle, and Upper Class.
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Pain Level Assessments – Scale from 1 (No Pain) to 10 (Severe Pain).
Why is Ordinal Data Important?
Ordinal data helps businesses, researchers, and analysts make informed decisions by ranking items based on preference or priority. It is used to:
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Measure Customer Experience – Helps businesses understand user satisfaction.
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Rank Preferences – Allows businesses to prioritize user choices and feedback.
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Compare Performance – Used in educational grading and job performance evaluations.
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Analyze Trends in Surveys – Enables structured interpretation of opinion-based research.
Ordinal Data vs. Nominal Data
While ordinal and nominal data are categorical, ordinal data includes an order, whereas nominal data does not.
| Feature | Ordinal data | Nominal data |
| Nature | Categorical & Ordered | Categorical only |
| Order | Yes | No |
| Interval consistency | No | No |
| Example | Satisfaction Ratings (Poor to Excellent) | Eye Colour, Nationality |
Real-World Use Cases of Ordinal Data
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E-Commerce – Customer review ratings (1-star to 5-star).
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Healthcare – Pain severity scales used by doctors.
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Education – Ranking students based on academic performance.
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HR & Job Recruitment – Employee performance assessments.