Asha owns a car-wash and is trying to decide whether or not to purchase a vending machine so customers
can buy coffee while they wait. She'll get the machine if she's convinced that more than 30% of her
customers would buy coffee. She plans on taking a random sample of n customers and asking them
whether or not they would buy coffee from the machine, and she'll then do a significance test using
a = 0.05 to see if the sample proportion who say "yes" is significantly greater than 30%.
Suppose that in reality, it is actually 33% of her customers that would buy coffee.
Which of the changes below would result in the highest power for her test?

Answer :

Answer: D

Step-by-step explanation:

She uses a sample size of n=200, and 50%  of all customers would actually buy coffee.

The change that would result in the highest power for her test is D. increase the significance level to α = 0.01 and use a sample size of n = 300.

What is significance level?

The significance level simply means the probability of rejecting the null hypothesis when it is true.

It should be noted that the power of the test depends on 4 factors which are the sample size, standard deviation, effect size, and significance level.

In the given scenario, the larger sample size will increase the power of the test and a higher significance level will result in a higher power.

Therefore, the test is done with the largest sample size and highest significance level of 0.10

Learn more about significance level on:

https://brainly.com/question/4599596

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