# Quiz 2 - Quiz 2 Prep 1 The probability of a Type I error is...

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Quiz 2 Prep1.The probability of a Type I error is denoted as _____.
2.A Type II error occurs in hypothesis testing when we _____.
3.YouTube would like to test the hypothesis that the average length of an online video watched by a user is more than 8 minutes. A random sample of 37 people watched online videos that averaged 8.7 minutes in length. It is believed that the population standard deviation for the length of online videos is 2.5 minutes. YouTube would like to set α= 0.02. The correct hypothesis statement for thishypothesis test would be _____.
4.A professor would like to test the hypothesis that the average number of minutes thata student needs to complete a statistics exam is equal to 45 minutes. A Type I error would occur if the professor concludes that the average exam time is
5.The power curve plots the power values of a hypothesis test over a range of corresponding sample means.
6.A hypothesis is an assumption about a population parameter such as a mean or a proportion.
7.The purpose of hypothesis statements is to draw a conclusion about the population parameters for which we do not have complete knowledge.
8.The only way to reduce both αand βsimultaneously in a hypothesis test is to increasethe sample size.
9.The alternative hypothesis, denoted by, represents the opposite of the null hypothesisand is believed to be true if the null hypothesis is found to be false.
10.The null hypothesis is also known as the research hypothesis because it representsthe position the researcher wants to establish.
11.If you are a researcher and the purpose of the hypothesis test is to prove that your findings are an improvement over the status quo, the condition that you are attempting to prove is assigned to the null hypothesis.
12.Historically, voter turnout for political elections in Texas have been reported to be 54%. You have been assigned by a polling company to test the hypothesis that voter turnout during the most recent election was higher than 54%. You have collected a random sample of 90 registered voters from this election and found that 54 actually voted. Use the critical value approach to test this hypothesis with a= 0.02.
Because zp= 1.14 is greater than za= 2.05, we fail to reject the null hypothesis. Therefore, you cannot conclude that the proportion of voter turnout exceeds 0.54.
13.Because hypothesis testing relies on a sample, we expose ourselves to the risk that our conclusions about the population will be wrong because of a sampling error.
14.When testing for the population mean when sigma is known and a sample size is greater than 30, the population must be normally distributed in order for the conclusions to be reliable.