If the quality of teaching is similar in a school, the scores on a standardized test will have a standard deviation of 29. The superintendent wants to know if there is a disparity in teaching quality, and decides to investigate whether the standard deviation of test scores has changed. She samples 24 random students and finds a mean score of 163 with a standard deviation of 20.7366. Is there evidence that the standard deviation of test scores has decreased at the α=0.005 level? Assume the population is normally distributed.
Step 2
Determine the critical value(s) of the test statistic. If the test is two-tailed, separate the values with a comma. Round your answer to three decimal places.
Step 3
Determine value of test statistic
Step 4
reject or fail to reject
Step 5
What is conclusion?
If the quality of teaching is similar in a school, the scores on a standardized test...
If the quality of teaching is similar in a school, the scores on a standardized test will have a standard deviation of 2424. The superintendent wants to know if there is a disparity in teaching quality, and decides to investigate whether the standard deviation of test scores has changed. She samples 2525 random students and finds a mean score of 145145 with a standard deviation of 10.215310.2153. Is there evidence that the standard deviation of test scores has decreased at...
In an annual report to investors, an investment firm claims that the share price of one of their bond funds had very little variability. The report shows the average price as $$12.00 with a variance of 0.22. One of the investors wants to investigate this claim. He takes a random sample of the share prices for 25 days throughout the last year and finds that the standard deviation of the share price is 0.1616. Can the investor conclude that the...
1. Find the P-value for the indicated hypothesis test with the given standardized test statistic, z. Decide whether to reject Upper H 0 for the given level of significance alpha. Two-tailed test with test statistic z= -1.95 and alpha=0.04 P-value= ? (Round to four decimal places as needed.) Reject H0 or fail to reject? 2. Find the critical value(s) for a left-tailed z-test with alpha=0.01. Include a graph with your answer. The critical value(s) is(are) ___ (Round to two...
Provide an appropriate response. Find the P-value for the hypothesis test with the standardized test statistic z. Decide whether to reject H o for the level of significance a. Two-tailed test z= 1.95 a = 0.05 0.0512; fail to reject Ho 0.0256; reject Ho 0.9744; fail to reject Ho 0.0512; reject Ho QUESTIO 8 points Save Answer Provide an appropriate response. Find the P-value for the hypothesis test with the standardized test statistic z. Decide whether to reject H o...
A standardized test is given to a sixth grade class. Histo deviation of performance may have recently changed. She randomly evidence that the standard deviation of test scores has increa rically, the test scores have had a standard deviation of 21. The believes that the standard sampled 30 students and found a mean of 160 with a standard deviation of 21.3846. Is there sed at the a 0.025 level? Assume the population is normally distributed Step 3 of 5: Determine...
Find the P value for the indicated hypothesis test with the given standardized test statistic z Decide whether to reject Ho for the given level of significance ? Right-tailed test with test statistic z-1.55 and ?-0.04 P-value(Round to four decimal places as needed.) State your conclusion O Reject Ho O Fail to reject Ho
3, Hypothesis testing for the mean (gis known) Find the P-value for a two-tailed hypothesis test with a standardized test statistic of z 1.64. Decide whether to reject Ho when the level of significance is α a. 0.10. b. Find the P-value for a right-tailed hypothesis test with a standardized test statistic of z 1.64. Decide whether to reject Ho when the level of significance is a0.10. Homeowners claim that the mean speed of automobiles traveling on their street is...
Find the value for the indicated hypothesis test with the given standardized test statistic, z. Decide whether to reject He for the given level of significance a Two-tailed test with test statistic zs - 1.99 and a=0.02 P value - (Round to four decimal places as needed.) State your conclusion Fail to reject He Reject Ho Click to select your answer(s).
Find the P-value for the indicated hypothesis test with the given standardized test statistic, z. Decide whether to reject Ho for the given level of significance a Right-tailed test with test statistic z = 1.32 and a = 0.03 P-value = (Round to four decimal places as needed.) State your conclusion O Reject Ho Fail to reject Ho
Find the P-value for the indicated hypothesis test with the given standardized test statistic, z. Decide whether to reject Hy for the given level of significance a. Two-tailed test with test statistic zs - 2.26 and 0.03 P-value = (Round to four decimal places as needed.) State your conclusion O Fail to reject Ho Reject Ho O