Exam 10: One-Sample Tests of Hypothesis

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

The probability of a Type II error is represented by the Greek symbol β.

Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign,a sample of 49 days of sales were taken. They found that the average daily sales were $6,300 per day. From past history,the restaurant knew that its population standard deviation is about $1,000. If the level of significance is 0.01,have sales increased as a result of the advertising campaign?

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 are the degrees of freedom?

Consider a two-tailed test with a level of confidence of 80.30%. The z-value is ________.

The probability of a Type II error is directly related to ________.

The mean length of a candy bar is 43 millimeters. There is concern that the settings of the machine cutting the bars have changed. Test the claim at the 0.02 level that there has been no change in the mean length. The alternate hypothesis is that there has been a change. Twelve bars (n = 12)were selected at random and their lengths in millimeters recorded. The lengths (in millimeters)are 42,39,42,45,43,40,39,41,40,42,43,and 42. The mean of the sample is 41.5 and the standard deviation is 1.784. If the computed t = −2.913,has there been a statistically significant change in the mean length of the bars?

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 ________.

Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign,a sample of 49 days of sales were taken. They found that the average daily sales were $6,300 per day. From past history,the restaurant knew that its population standard deviation is about $1,000. If the level of significance is 0.05,have sales increased as a result of the advertising campaign?

Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign,a sample of 49 days of sales were taken. They found that the average daily sales were $6,300 per day. From past history,the restaurant knew that its population standard deviation is about $1,000. If the level of significance is 0.025,have sales increased as a result of the advertising campaign?

For a two-tailed test with a 0.05 significance level,where is the rejection region when n is large and the population standard deviation is known?

A null hypothesis makes a claim about a ________.

What are the critical z-values for a two-tailed hypothesis test if α = 0.01?

The average cost of tuition plus room and board for a small private liberal arts college is reported to be $8,500 per term,but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let α = 0.05. Based on the computed test statistic or p-value,what is our decision about the average cost?

What are the critical values for a two-tailed test with a 0.01 level of significance when n is large and the population standard deviation is known?

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

A random sample of size 15 is selected from a normal population. The population standard deviation is unknown. Assume the null hypothesis indicates a two-tailed test and the researcher decided to use the 0.10 significance level. For what values of t will the null hypothesis not be rejected?

If we reject the null hypothesis,what can we conclude subject to the probability,α?

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. The null hypothesis is ________.