Question

My statistics book says there are 8 degrees of freedom for this data set. I don't understand how they got that number. # of Books Education Level 68 11 345 15 276 16 756 12 43 6 546 14 58 6 187 14 286 9 93 8 376 11 623 18 876 12 28 4 289 15

Answer 1

It's a bit unclear with the table this way, but I count fifteen points, fifteen lines of the table, each a pair of numbers.

That's 15 degrees of freedom in the data. When modeling, each parameter in the model uses up one degree of freedom, so you'd use a smaller number of degrees of freedom when calculating t statistics, etc.