Question

Which of these variables are nominal variables?
Age
Gender
Reported calcium level (mmol/L) for each patient
Reported phosphorus level (mmol/L) for each patient
Reported alkaline phosphatase level (IU/L) for each patient
Six laboratories (coded as 1 to 6 in the dataset).
Five age groups (65-69, 70- 74, 75-79, 80-84, 85-89)

Answer 1

Variables which are qualitative or categorical are called nominal variable .

We cannot not use nominal data for mathematical calculations.

In the given question gender and six laboratories (codes as 1 to 6 in the dataset ) are nominal variables .

Because variable gender is classified in three categories. Also laboratories are labelled 1 to 6 . Numbers 1, 2 ,3, 4, 5 ,6 are labels of six laboratories.

Remaining variables given in the question such as age , reported calcium level , phosphorus , alkaline phosphate levels and age groups are quantitative variables .