Spam filters in an email program are similar to hypothesis tests in that there are two possible decisions and two possible realities and therefore two kinds of errors that can be made. The hypotheses can be considered as:

H₀: Incoming email message is legitimate.
H_a: Incoming email message is spam.
a. Describe what rejecting H₀ means in this context.
b. Describe what failing to reject H₀ means in this context.
c. Describe what Type I error means in this context.
d. Describe what Type II error means in this context.