5) You are disappointed to find that your 15-item depression inventory has an alpha of .50. You are fairly certain you can come up with additional items that are equally good.

a) Give your best prophecy for how many additional items would need to be added to your inventory to achieve a reliability of .80. (2 marks)

b) Under what conditions might your prophecy above fail to be fulfilled? (2 marks)

c) Other than creating additional items, what else might you do to increase the reliability of your depression inventory data? (2 marks)