Which description matches nominal data?

• A. It can be ordered
• B. It can take any value in a range
• C. It cannot be ordered
• D. It has a natural zero

Answer: (C)

Nominal data are categories used for labeling attributes with no inherent order. Each category is just a label; there isn’t a meaningful way to say one category comes before another or that there are distances between categories. Because of that, they cannot be ordered, which is why this description fits best. You can count how many items fall into each category, but you wouldn’t compute meaningful averages or differences between categories. By contrast, data that can be ordered have a natural ranking (ordinal data), and numeric scales (interval/ratio) have meaningful distances, with a natural zero occurring in ratio data.