Exam 10: One-Sample Tests of Hypothesis

The Greek letter used to represent the probability of a Type I error is alpha (α).

Consider a right-tailed test (upper tail) and a sample size of 40 at the 95% confidence level. The value of t is ________.

A test statistic is a value computed from sample information that is used to test the null hypothesis.

The waiting time for patients at a local walk-in health clinic follows a normal distribution with a mean of 15 minutes and a population standard deviation of 5 minutes. The quality-assurance department sampled 50 patients and found that the mean waiting time was 14.25 minutes. At the 0.025 significance level, decide if the sample data support the claim that the mean waiting time is less than 15 minutes. State your decision in terms of the null hypothesis.

A statement about the value of a population parameter is called a ________________.

A machine is set to fill the small-size packages of M&M candies with 56 candies per bag. A sample revealed: three bags of 56, two bags of 57, one bag of 55, and two bags of 58. To test the hypothesis that the mean candies per bag is 56, how many degrees of freedom are there?

Which of the following is NOT one of the six steps in the hypothesis testing procedure?

An alternate hypothesis is a statement about a population parameter that is accepted when the null hypothesis is rejected.

A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the sample variance?

If the null hypothesis is true and the researchers reject it, a ________ error has been made.

The waiting time for patients at a local walk-in health clinic follows a normal distribution with a mean of 15 minutes and a population standard deviation of 5 minutes. The quality-assurance department sampled 50 patients and found that the mean waiting time was 14.25 minutes. What is the test statistic?

What is a Type II error?

Records on a fleet of trucks reveal that the average life of a set of spark plugs is normally distributed with a mean of 22,100 miles. The fleet owner purchased 18 sets and found that the sample average life was 23,400 miles; the sample standard deviation was 1,412 miles. To determine if the spark plugs average 22,100 miles, what is the critical value for the test using a 0.05 level of significance?

An example of a hypothesis is: A person is innocent until proven guilty.

The critical t statistic for the alternative hypothesis, H₁: µ < 12, a 0.005 level of significance, and a sample size of 20 is ______.

Consider a two-tailed test with a level of confidence of 99%. The p-value is determined to be 0.05. Therefore, the null hypothesis ________.

If the null hypothesis is false and the researchers do not reject it, a Type I error has been made.

The p-value is determined by the value of a ______________________.

A manufacturer wants to increase the shelf life of a line of cake mixes. Past records indicate that the average shelf life of the mix is 216 days. After a revised mix has been developed, a sample of nine boxes of cake mix had a mean of 217.222 days and a standard deviation of 1.2019 days. At the 0.025 significance level, what is the critical value?

A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the sample mean?