Lady Hawkins only

Value Ranges: heights: 5-9, 5-11, 6-0, 6-1, 6-2, 6-3, 6-4, 6-5, 6-6, 6-7, 6-8, 6-9, 6-10, 6-11, 7-0, 7-1, 7-2

Data Source: http://stats.nba.com/

Research question: “Is there a relationship between height and free throw statistics?”

You want to have only one dependent variable and numerous independent variables. 

“Is there a relationship between height and free throw statistics?” You could  use height as the dependent variable.  Your three categories can be the independent variable 1. sum of free throws attempted,  2. sum of free throws made, 3. average free throw percentage as three different independent variables.  This will determine if there is a relationship between various free throw stats and height.   

You will want to run an individual regression model on each independent variable and then one combined multiple regression model.