Question

Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...

Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent.

Time A B C F Row Total
1 h 25 44 57 12 138
Unlimited 15 47 82 18 162
Column Total 40 91 139 30 300

(i) Give the value of the level of significance.


State the null and alternate hypotheses.

H0: Time to take a test and test score are not independent.
H1: Time to take a test and test score are independent.H0: Time to take a test and test score are independent.
H1: Time to take a test and test score are not independent.    H0: The distributions for a timed test and an unlimited test are the same.
H1: The distributions for a timed test and an unlimited test are different.H0: The distributions for a timed test and an unlimited test are different.
H1: The distributions for a timed test and an unlimited test are the same.


(ii) Find the sample test statistic. (Round your answer to two decimal places.)


(iii) Find or estimate the P-value of the sample test statistic.

P-value > 0.1000.050 < P-value < 0.100    0.025 < P-value < 0.0500.010 < P-value < 0.0250.005 < P-value < 0.010P-value < 0.005


(iv) Conclude the test.

Since the P-value < α, we do not reject the null hypothesis.Since the P-value is ≥ α, we do not reject the null hypothesis.    Since the P-value < α, we reject the null hypothesis.Since the P-value ≥ α, we reject the null hypothesis.


(v) Interpret the conclusion in the context of the application.

At the 1% level of significance, there is insufficient evidence to claim that time to do a test and test results are not independent.At the 1% level of significance, there is sufficient evidence to claim that time to do a test and test results are not independent.    

Homework Answers

Answer #1

The statistical software output for this problem is :

(i)

H0: Time to take a test and test score are independent.
H1: Time to take a test and test score are not independent.

(ii)

sample test statistic = 6.42

(iii)

0.050 < P-value < 0.100  

(iv)

Since the P-value is ≥ α, we do not reject the null hypothesis.

(v)

At the 1% level of significance, there is insufficient evidence to claim that time to do a test and test results are not independent.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a...
Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the following table. Test at the 0.01 level of significance that time to complete a test and test results are independent. Time A...
The types of raw materials used to construct stone tools found at an archaeological site are...
The types of raw materials used to construct stone tools found at an archaeological site are shown below. A random sample of 1486 stone tools were obtained from a current excavation site. Raw Material Regional Percent of Stone Tools Observed Number of Tools as Current excavation Site Basalt 61.3% 912 Obsidian 10.6% 163 Welded Tuff 11.4% 176 Pedemal chert 13.1% 186 Other 3.6% 49 Use a 1% level of significance to test the claim that the regional distribution of raw...