NOIR refers to which of the following?

• A. The four levels of measurement
• B. A data collection method
• C. A sampling technique
• D. A research ethics framework

Answer: (A)

NOIR refers to the four levels of measurement—nominal, ordinal, interval, and ratio. This classification shows what you can legitimately do with data and which analyses are appropriate. Nominal data categorize without order (like gender or color). Ordinal data introduce order but not equal gaps between ranks. Interval data have equal gaps between values but no true zero (such as Celsius temperature). Ratio data have equal intervals and a true zero (such as height or weight). Because the level of measurement determines which summaries and tests make sense, NOIR is the framework for choosing the right statistical methods. It isn’t about data collection methods, sampling techniques, or ethics frameworks.