Exam 9: Hypothesis Tests

The average hourly wage of computer programmers with 2 years of experience has been $21.80.Because of high demand for computer programmers, it is believed there has been a significant increase in the average hourly wage of computer programmers.To test whether or not there has been an increase, the correct hypotheses to be tested are

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%.At the .05 level of significance, it can be concluded that the proportion of the population in favor of candidate A is

​When the null hypothesis is rejected, it is​

A Type I error is committed when​

A machine is designed to fill toothpaste tubes, on an average, with 5.8 ounces of toothpaste.The manufacturer does not want any underfilling or overfilling.The correct hypotheses to be tested are

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

Read the z statistic from the normal distribution table and circle the correct answer.For a one-tailed test (upper tail) at α = .0630, z =

In hypothesis testing, if the null hypothesis has been rejected when the alternative hypothesis has been true,

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

A random sample of 16 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

If the null hypothesis is rejected in hypothesis testing,

The p-value is a probability that measures the support (or lack of support) for

For a one-tailed hypothesis test (upper tail), the p-value is computed to be .034.If the test is being conducted at the 5% level of significance, the null hypothesis

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

Read the t statistic from the t distribution table and circle the correct answer.For a one-tailed test (lower tail) with 22 degrees of freedom at α = .05, the value of t =

A grocery store has an average sales of $8000 per day.The store introduced several advertising campaigns in order to increase sales.To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected.It was found that the average was $8300 per day.From past information, it is known that the standard deviation of the population is $1200.The correct null hypothesis for this problem is

A sample of 1400 items had 280 defective items.For the following hypothesis test, ​ H₀: p ≤ .20 H_a: p > .20 ​ The test statistic is

As the test statistic becomes larger, the p-value

Read the t statistic from the t distribution table and circle the correct answer.For a two-tailed test with a sample size of 20 and using α = .20, t =

Read the z statistic from the normal distribution table and circle the correct answer.For a two-tailed test using α = .0160, z =