Number of variables (k)
What does k mean in a dataset?
How many variables a dataset has, written k.
Count the columns of your dataset and you have the number of variables, which we write as a lowercase k. Together, n and k describe the size of a dataset: n rows of observations by k columns of variables.
Each new question you add to your interviews adds one to k, and each new person you interview adds one to n.
From our own dataset
A table with a Nickname column and one column for each interview question has k equal to the number of questions plus one.
Where we teach it
Lesson 1.2 of Project 1: Sibling Interviews. Watch lesson 1.2 and read the notes, free with a free account.
Related terms
- Variable: A characteristic or question we record for each observation.
- Column: A vertical line of cells.
- Number of observations (n): How many observations a dataset has, written n. Also called the sample size.