500 câu trắc nghiệm Kinh tế lượng – 8B

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
Use the traditional method to test the given hypothesis. Assume that the samples are independent and that they have been randomly selected
7) In a random sample of 500 people aged 20-24, 22% were smokers. In a random sample of 450 people aged 25-29, 14% were smokers. Test the claim that the proportion of smokers in the two age groups is the same. Use a significance level of 0.01.

H0: p1 = p2. H1: p1 ≠ p2.
Test statistic: z = 3.19. Critical values: z = -2.575, 2.575.
Reject the null hypothesis. There is sufficient evidence to warrant rejection of the claim that the proportion of smokers in the two age groups is the same.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Determine whether the samples are independent or consist of matched pairs.
8) The effectiveness of a headache medicine is tested by measuring the intensity of a headache in patients before and after drug treatment. The data consist of before and after intensities for each patient.
● Matched pairs
○ Independent samples
Construct the indicated confidence interval for the difference between population proportions p1 – p2. Assume that the samples are independent and that they have been randomly selected.
9) A marketing survey involves product recognition in New York and California. Of 558 New Yorkers surveyed, 193 knew the product while 196 out of 614 Californians knew the product. Construct a 99% confidence interval for the difference between the two population proportions.
○ -0.0034 < p1 – p2 < 0.0566
○ 0.0247 < p1 – p2 < 0.0286
○ -0.0177 < p1 – p2 < 0.1243
● -0.0443 < p1 – p2 < 0.0976

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
Test the indicated claim about the means of two populations. Assume that the two samples are independent and that they have been randomly selected.
10) Two types of flares are tested for their burning times (in minutes) and sample results are given
below.

Refer to the sample data to test the claim that the two populations have equal means. Use a 0.05 significance level.

H0: \({\mu _1} = {\mu _2}\). H1: \({\mu _1} ≠ {\mu _2}\).
Test statistic t = 16.025. Critical values: t = 2.032, -2.032.
Reject the null hypothesis. There is sufficient evidence to warrant rejection of the claim that the two populations have equal means.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Construct the indicated confidence interval for the difference between the two population means. Assume that the two samples are independent and that they have been randomly selected.
11) A researcher wishes to determine whether people with high blood pressure can reduce their blood pressure by following a particular diet. Use the sample data below to construct a 99% confidence interval for u1 – u2 where u1 and u2 represent the mean for the treatment group and the control group respectively.

○ -29.0 < \({\mu _1} – {\mu _2}\) < -0.2
○ -1.3 < \({\mu _1} – {\mu _2}\) < 30.5
○ -26.7 < \({\mu _1} – {\mu _2}\) < -2.5
● -30.5 < \({\mu _1} – {\mu _2}\) < 1.3

The two data sets are dependent. Find \(\bar d\) to the nearest tenth.

12)

○ -10.2
○ -1.0
● -1.7
○ -2.2

Find sd.
13) The differences between two sets of dependent data are 0.42 0.42 0.51 0.54 0.6. Round to the nearest hundredth.
● 0.08
○ 0.24
○ 0.12
○ 0.04