Exam 9: Hypothesis Tests

Read the t statistic from the t distribution table and choose the correct answer.For a one-tailed test (lower tail), using a sample size of 14, and at the 5% level of significance, t =

For a two-tailed test, the p-value is the probability of obtaining a value for the test statistic as

From a population of cans of coffee marked "12 ounces," a sample of 50 cans was selected and the contents of each can were weighed.The sample revealed a mean of 11.8 ounces with a standard deviation of .5 ounces. a. Formulate the hypotheses to test if the mean weight of the population is at least 12 ounces. b. Compute the test statistic. c. Using the p-value approach, what is your conclusion? Let α = .05.

For a given sample size in hypothesis testing,

If a hypothesis test leads to the rejection of the null hypothesis, a _____ have been committed.

In order to test the following hypotheses at an α level of significance ​ H₀: μ 800 H_a: μ > 800 ​ The null hypothesis will be rejected, if the test statistic z is

A random sample of 25 students selected from the student body of a large university had an average age of 25 years and a standard deviation of 2 years.We want to determine if the average age of all the students at the university is significantly more than 24.Assume the distribution of the population of ages is normal.Using α = .05, it can be concluded that the population mean age is

Read the z statistic from the normal distribution table and choose the correct answer.For a one-tailed test (lower tail) using α = .005, z =

A weatherman stated that the average temperature during July in Chattanooga is 80 degrees or less.A sample of 32 Julys is taken to test the weatherman's statement.The correct set of hypotheses is

The error of rejecting a true null hypothesis is

For a lower tail test, the p-value is the probability of obtaining a value for the test statistic at least as

In the last presidential election, a national survey company claimed that no more than 50% (i.e., < 50%) of all registered voters voted for the Republican candidate.In a random sample of 400 registered voters, 208 voted for the Republican candidate. a. State the null and the alternative hypotheses. b. Compute the test statistic. c. Compute the p-value, and test the hypotheses using a 5% level of significance.

A random sample of 100 people was taken.Eighty-five of the people in the sample favored Candidate A.We are interested in determining whether or not the proportion of the population in favor of Candidate A is significantly more than 80%.The p-value is

For a one-tailed hypothesis test (upper tail), the p-value is computed to be .034.If the test is being conducted at the 1% level of significance, the null hypothesis

An assumption made about the value of a population parameter is called a(n)

If the null hypothesis is not rejected at the 5% level of significance, it _____ rejected at the 1% level.

In a one-tailed hypothesis test (lower tail), the test statistic is determined to be 2.The p-value for this test is

More evidence against H₀ is indicated by​

Choo Choo Paper Company makes various types of paper products.One of their products is a 30 mils thick paper.In order to ensure that the thickness of the paper meets the 30 mils specification, random cuts of paper are selected and the thickness of each cut is measured.A sample of 256 cuts had a mean thickness of 30.3 mils with a standard deviation of 4 mils. a. Compute the standard error of the mean. b. b. At the .05 level of significance using the critical value approach, test to see if the mean thickness is significantly more than 30 mils. c. Show that the p-value approach results in the same conclusion as that of part

If the cost of making a Type I error is high, a smaller value should be chosen for the​