Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Grandma’s birthday is coming up and my kids are both excited to get her the perf

ID: 3341153 • Letter: G

Question

Grandma’s birthday is coming up and my kids are both excited to get her the perfect gift. We have 2 different colors of wrapping paper at home, Green and Red. Child A loves Green and Red and gravitates toward Red 60% of the time and Child B also loves Green and Red but gravitates toward Red 30% of the time. If on Grandma’s birthday she gets a gift that is wrapped in Red wrapping paper she will conclude that Child A gave her the gift, and if she gets a gift that is wrapped in Green wrapping paper, she will conclude that Child B gave her the gift. Statistically speaking, the following hypotheses and rejection rule have been stated: H0: The gift comes from Child A; that is, the P(wrapping paper is Red | gift comes from Child A) = 0.60. Ha: The gift comes from Child B; that is, the P(wrapping paper is Red | gift comes from Child B) = 0.30. When grandma gets her gift, her decision rule wll be: Reject H0 if the wrapping paper is Green and thus fail to reject H0 if the wrapping paper is Red. For this situation, what is the probability of committing a Type II error? a) 0.05 b) 0.10 c) 0.20 d) 0.30 e) 0.40 f) 0.50 g) 0.60 h) 0.70

Explanation / Answer

Here, P(wrapping paper is Red | gift comes from Child A) = 0.60

P(wrapping paper is Red | gift comes from Child B) = 0.30

Null Hypothesis is H0: The gift comes from Child A

When grandma gets her gift, her decision rule is: Reject H0 if the wrapping paper is Green

So, The probability of committing a Type II error

=Probability of accepting the hypothesis when it is actually false

=Probability that grandma concludes the gift is from child A(ie, she receives the gift wrapped in red paper), when actually it is from child B

=P(wrapping paper is Red | gift comes from Child B)

= 0.30 [Option d ]