Problem 33

  1. H0: The computer fine HA: The computer is damaged.
  2. Some good computers (20%) will be seen as damaged. But all broekn ones will be known to be broken.
  3. 3+
  4. 20%
  5. With a 2% alpha, power will be increased to ~90%.

Problem 34

  1. As sample size increase, power increases
  2. Power decreases as alpha level decreases

Problem 35

H0: p=0.66

p value = 0.0228

His ratings were actually probably better than the null, so we reject the null since the p value is below our alpha level.

Problem 36

Yes, the sample size is large and the conditions are met (10%, random sample). The p value is almost 0, meaning that there is almost certianly been an increase in the true proportion of grades above 3.5.

Problem 37

  1. The company wants to know that the athlete is renowned
  2. Type 1 Company thinks the athelete is well known, but he’s not.

Type 2 Company thinkgs the athelete is not well know, but he is. c) Type 1 more probable than type 2

Problem 38

Even thought the star is above the 25% threshold at 27%, the probabilty that these results were due to random sampling variation are too high for the comopnay to reject the null. Therefore, they wont sign the contract.

Problem 39

I’m 95% confident that the true proportion of people who want a nuclear power plant near them versus not near them is higher by 7 to 19%.