Question

5. Which of the following would be an appropriate Alternative Hypothesis? A) The mean of a population is equal to 60 B) The mean of a sample is equal to 60 C) The mean of a population is not equal to 60 D) The mean of a sample is not equal to 60 E) All of the above 6. Which of the following statements about the level of significance in a hypothesis test is true? A) The larger the level of significance, the more likely you are to reject the null hypothesis. B) The larger the level of significance, the smaller the magnitude of the critical z-scores. C) The level of significance is also denoted a D) All of the above statements are true. 7. The owner of a local nightclub has recently surveyed a random sample of n = 300 customers of the club. She would now like to determine whether or not the mean of her customers is younger than 32. If so, she plans to alter the entertainment to appeal to a younger crowd. If not, no entertainment changes will be made. The appropriate hypothesis test is: A) Hn: u = 32 vs. Ha: u > 32 B) Hn: u = 32 vs. Ha: u < 32 C) HniH + 32 vs. Hau 32 D) HN: x-bar = 32 vs. x-bar: u < 32

Answer 1

Solution:

Question 5)

Null hypothesis always = type whereas alternative is < or > or not equal to type.

Hypothesis statement are about population parameters , not about sample statistic.

Thus option B and D are not correct.

Now from option A and C, option A is equal to type , so this is not correct for alternative hypothesis.

Thus correct option is :

C. The mean of the population is not equal to 60

Question 6)

Level of significance is denoted by $\alpha$ which is nothing but rejection region, if it gets larger , then rejection increases and hence there is more chance of rejecting null hypothesis.

Also if it gets larger, we get smaller z values.

For example: z value for 0.05 level of significance is 1.645 and z value for 0.10 level of significance =1.28

thus correct option is:

D. All of the above statements are true.

Question 7)

We have to test whether or not the mean of customers is younger than 32.

That means: test if mean is less than 32 or not.

Thus correct option is:
B) $H_{N}: \mu = 32 \: \: \: Vs \: \: \: H_{A}: \mu <32$