Question 8.24

8.24 Even more on bias and reliability. Exercise 8.22 gives five true values for lengths. A subject measures the first length (true length = 2.9 inches) four times by eye. His measurements are

3.0 2.9 3.1 3.0

Suppose his measurements have a bias of +0.1 inch.

  1. (a) What are the four random errors for his measurements?

  2. (b) What is the variance of his four measurements?