Exam 10: One-Sample Tests of Hypothesis

Which symbol is a test statistic used to test a hypothesis about a population mean?

The probability of a Type I error is also referred to as alpha.

What is the critical value for a one-tailed hypothesis test in which a null hypothesis is tested at the 5% level of significance based on a sample size of 25?

When testing a hypothesis about a proportion,the data collection is based on counting something.

The mean weight of newborn infants at a community hospital 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 standard deviation?

Type II error is the probability or risk of rejecting a null hypothesis when it is actually true.

What is the test of hypothesis when the alternate hypothesis states a direction? ________________________

As sample sizes decrease,we are more confident in sample estimates of population parameters.

The 0.05 level of significance is applied to all studies involving sampling.

The mean weight of newborn infants at a community hospital 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 decision for a statistical significant change in average weights at birth at the 5% level of significance?

A manufacturer claims that less than 1% of all his products do not meet the minimum government standards.A survey of 500 products revealed ten did not meet the standard.What is the p-value? _______________

What is another name for the alternate hypothesis?

A nationwide survey of college students was conducted and found that students spend two hours per class hour studying.A professor at your college wants to determine whether the time students spend at your college is significantly different from two hours.A random sample of fifteen statistics students is carried out and the findings indicate an average of 1.75 hours with a standard deviation of 0.24 hours.The t-test is to be conducted at the 5% level of significance.What is our decision? _______________

If the critical z-value for a test statistic equals 2.45,what value of the test statistic would provide the least chance of making a Type I error?

The mean weight of newborn infants at a community hospital 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

Based on the Nielsen ratings,the local CBS affiliate claims its 11:00 PM newscast reaches 41% of the viewing audience in the area.In a survey of 100 viewers,36% indicated that they watch the late evening news on this local CBS station.What is the critical value if the level of significance is 0.10?

The mean weight of newborn infants at a community hospital 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 alternate hypothesis?

A Type I error is the probability of accepting a true null hypothesis.

Hypothesis testing is a procedure that uses sample evidence and probability theory to decide whether to reject or fail to reject a hypothesis.

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.A manufacturer of spark plugs claims that its plugs have an average life in excess 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 1,500 miles and the computed t = 3.677.Based on these findings,there is enough evidence to accept the manufacturer's claim at the 0.05 level.