BUS105 SECOND TRY

Q There is a five-step procedure that systematizes hypothesis testing. Which is not a step in this procedure?

I. Construct a confidence interval.

II. Select the level of significance.

III. Select the test statistic.

A I only

Q When a hypothesis test is setup and the null hypothesis includes the term "=", then the test is a

A Two-tailed test.

Q Instant Beverages, Inc believe that they supply to more than 40% of the restaurants. A random survey found that 75 of the 170 restaurants surveyed purchased ice from this manufacturer. If we want to conduct a statistical test for this problem, the alternative hypothesis would be

A the population proportion is > 0.40

Q ______ is the value that is the crossover point between the region where the null hypothesis is not rejected and the region where it is rejected.

A Critical value

Q In a five-step procedure that systematizes hypothesis testing, what is the first step?

I. State the null hypothesis (H₀) and the alternate hypothesis (H₁).

II. Select the level of significance.

III. Select the test statistic.

A I only

Q A ________ is a single value (statistic) used to estimate a population value (parameter) whereas a ________ is a range of values within which the population parameter is expected to be found.

A point estimate; confidence interval

Q _______ is a statement or claim about the value of a population parameter. It suggests a change in the population parameter.

A Hypothesis

Q To execute an appropriate hypothesis testing, the_________ divides the rejection and non-rejection regions.

A critical values.

Q If the alternative hypothesis in a hypothesis test includes the term "≠", then the test is a

A Two-tailed test.

Q We should use _________ when the samples are chosen at random and are not related to each other.

A Independent samples

Q In performing a hypothesis test, the null hypothesis is population mean = 6.9 and the alternative hypothesis is population mean ≠ 6.9, a random sample of 16 items is selected. The sample mean is 7.1 and the sample standard deviation is 2.0. The population is approximated to be normal. What is the value of calculated t for this test?

A 0.40

Q When should a paired t test be used?

I. There are 2 independent samples. The samples are drawn from different or independent populations. The means of each sample are used to derive the test statistic.

II. There are dependent samples. The samples are drawn from the same population or dependent populations. The means of the difference of the dependent observations are used to derive the test statistic.

III. There is only one sample. This sample is divided into 2 sub-groups. The means of each sub group are used to derive the test statistic.

A II only

Q What are factors that determine the sample size when we wish to estimate a proportion?

I. Desired level of confidence.

II. Maximum allowable error.

III. Sample proportion

A I, II & III

Q If the alternative hypothesis in a hypothesis test includes phrases like “improved”, “declined”, “has reduced” or “has increased”, the test should be

A None of the listed choices.

Q _______ is the probability computed for the value of the test statistic which is at least as extreme as the one found in the sample data when the null hypothesis is true.

A p-value

Q In comparing two population means we wish to know whether they could be equal. What is the suitable hypothesis test to conduct?

A A two-sample test because we are investigating whether the distribution of the difference between the sample means could have a mean of 0.

Q When the sample size increases, the

I. population mean increases.

II. sampling distribution mean increases.

III. population standard deviation decreases.

A None of the listed choices

Q A one-tail hypothesis test was conducted with a large sample size and the observed z value of 2.33 was obtained. What is the p-value for this z?

A 0.0099.

Q In order to conduct a 2 sample pooled t-test,

I.     we assume that the samples are from independent populations which are approximately 

      normal.

II.   the sample sizes must be the same.

III.  we assume that the standard deviations of the sampled populations are almost equal.

A I Only

Q Execute an appropriate hypothesis test with p-value=0.02. Which of the following could be a correct conclusion?

A reject the null hypothesis if the level of significance is set at 5% but do not reject if the level of significance is set at 1%.

RESULTS: 90/100