CompTIA Data+ (DA0-002)Data Concepts and EnvironmentsEasy
A data scientist is preparing a dataset for machine learning. The dataset includes a column named 'CustomerID' which contains unique alphanumeric identifiers for each customer. This column is used solely to distinguish one customer from another and has no inherent order or numerical meaning. What type of data does 'CustomerID' represent?
- ARatio data
- BNominal data
- COrdinal data
- DInterval data
Show answer & explanationAnswer & explanation
Correct answer: B. Nominal data
Nominal data consists of categories that have no inherent order or numerical value. 'CustomerID' serves only to name or label an individual record, without any quantitative significance or order.
Why the other options are wrong
- A. Ratio data has a true zero point and allows for all arithmetic operations, which is not applicable to an ID.
- C. Ordinal data has categories with a meaningful order, which 'CustomerID' does not possess.
- D. Interval data has ordered categories with equal intervals, but 'CustomerID' has no inherent order or intervals.
Nominal Data
A type of categorical data where categories have no intrinsic order or numerical value, serving only as labels.
- Categories are distinct and mutually exclusive
- No inherent order or ranking
- Cannot perform arithmetic operations
- Examples: Gender, CustomerID, City
Memory trick: N-O-I-R: N-o Order, O-rder, I-ntervals, R-atio.