Exam 9: Hypothesis Tests

The error of rejecting a true null hypothesis is

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

​For a sample size of 30, changing from using the standard normal distribution to using the t distribution in a hypothesis test,

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

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 100 days of sales was selected. It was found that the average was $8200 per day. From past information, it is known that the standard deviation of the population is $1500. The correct null hypothesis for this problem is

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

In a lower tail hypothesis test situation, the p-value is determined to be .2. If the sample size for this test is 41, the t statistic has a value of

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

A Type II error is committed when

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

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

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 =

The level of significance is the

Read the t statistic from the t distribution table and choose the correct answer. For a one-tailed test (upper tail) with a sample size of 16 and at the .10 level, t =

The probability of making a Type II error is denoted by

Read the z statistic from the normal distribution table and choose the correct answer. For a one-tailed test (lower tail) using α = .0901, z =

A Type I error is committed when​

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

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

For a two-tailed hypothesis test about ?, we can use any of the following approaches except