Mathematical Statistics with Applications
7th Edition
ISBN: 9781111798789
Author: Dennis O. Wackerly
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 15.3, Problem 8E
Refer to Exercise 12.15. Using the sign test, do you find sufficient evidence to support concluding that completion times differ for the two populations? Use α = .10.
A plant manager, in deciding whether to purchase a machine of design A or design B, checks the times for completing a certain task on each machine. Eight technicians were used in the experiment, with each technician using both machine A and machine B in a randomized order. The times (in seconds) required to complete the task are given in the accompanying table.
- a Test to see if there is a significant difference between mean completion times, at the 5% significance level.
- b Do you think pairing on technicians was worthwhile in this case? Explain.
- c What assumptions are necessary for the test in part (a)?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A nutritionist compared the effectiveness of an online diet program to that of an in-person diet program. After three months, she compared the number of pounds of weight lost. The control group (in-person) lost a mean of 18.00 pounds (s = 14.50, n = 16) and the experimental group (online) lost 16.00 pounds (s = 13.30, n = 21). Use an alpha of .05, a two-tailed test, s2pooled = 191.19, and sM1−M2 = 4.5 to determine if there is a difference between the two programs.
In a study of the effectiveness of a fabric device that acts like a support stocking for a weak or damaged heart, 110 people who consented to treatment were assigned at random to either a standard treatment consisting of drugs or the experimental treatment that consisted of drugs plus surgery to install the stocking. After two years, 30% of the 60 patients receiving the stocking had improved and 24% of the patients receiving the standard treatment had improved. (Use a statistical computer package to calculate the P-value. Use pexperimental − pstandard. Round your test statistic to two decimal places and your P-value to four decimal places.)
z
= ?
P
= ?
A research study recruited 32 adolescent patients with Type 1 diabetes. In random order, each patient received therapy with a bionic pancreas for 5 days and therapy with an insulin pump for 5 days. Is there evidence that, on average, a bionic pancreas helps patients attain a lower plasma glucose level than an insulin pump?
Which test is most appropriate for this scenario?
1-sample z-test for proportions
B
matched-pairs
C
1-sample t-test for means
D
2-sample test for proportions
E
2-sample test for means
Chapter 15 Solutions
Mathematical Statistics with Applications
Ch. 15.3 - What significance levels between = .01 and = .15...Ch. 15.3 - Prob. 2ECh. 15.3 - Clinical data concerning the effectiveness of two...Ch. 15.3 - Prob. 4ECh. 15.3 - New food products are frequently subjected to...Ch. 15.3 - On clear, cold nights in the central Florida...Ch. 15.3 - A psychological experiment was conducted to...Ch. 15.3 - Refer to Exercise 12.15. Using the sign test, do...Ch. 15.3 - Prob. 9ECh. 15.4 - The accompanying table gives the scores of a group...
Ch. 15.4 - Refer to Exercise 15.4. What answers are obtained...Ch. 15.4 - Refer to Exercise 15.6(a). Answer the question by...Ch. 15.4 - Eight subjects were asked to perform a simple...Ch. 15.4 - Two methods, A and B, for controlling traffic were...Ch. 15.4 - Dental researchers have developed a new material...Ch. 15.4 - Refer to Exercise 12.16. With = .01, use the...Ch. 15.4 - Suppose that Y1, Y2,, Yn is a random sample from a...Ch. 15.4 - The spokesperson for an organization supporting...Ch. 15.6 - Find the p-values associated with each of the...Ch. 15.6 - In some tests of healthy, elderly men, a new drug...Ch. 15.6 - Two plastics, each produced by a different...Ch. 15.6 - Prob. 24ECh. 15.6 - Prob. 25ECh. 15.6 - Prob. 26ECh. 15.6 - Prob. 27ECh. 15.6 - Prob. 28ECh. 15.7 - The table that follows contains data on the leaf...Ch. 15.7 - Prob. 30ECh. 15.7 - Three different brands of magnetron tubes (the key...Ch. 15.7 - An experiment was conducted to compare the length...Ch. 15.7 - Prob. 33ECh. 15.7 - Prob. 34ECh. 15.7 - Prob. 35ECh. 15.8 - In a study of palatability of antibiotics for...Ch. 15.8 - Prob. 38ECh. 15.8 - Prob. 39ECh. 15.8 - A serious drought-related problem for farmers is...Ch. 15.8 - Prob. 41ECh. 15.8 - Prob. 42ECh. 15.8 - Prob. 43ECh. 15.8 - Prob. 44ECh. 15.8 - Prob. 45ECh. 15.9 - Prob. 46ECh. 15.9 - Prob. 47ECh. 15.9 - Prob. 48ECh. 15.9 - Prob. 49ECh. 15.9 - Prob. 50ECh. 15.9 - Prob. 52ECh. 15.10 - Prob. 53ECh. 15.10 - Prob. 54ECh. 15.10 - Prob. 55ECh. 15.10 - Prob. 56ECh. 15.10 - Prob. 57ECh. 15.10 - Prob. 58ECh. 15.10 - Refer to Exercise 11.4. Regard both book and...Ch. 15.10 - Prob. 60ECh. 15 - Prob. 62SECh. 15 - Prob. 63SECh. 15 - Prob. 64SECh. 15 - Prob. 65SECh. 15 - Prob. 67SECh. 15 - Prob. 69SECh. 15 - Prob. 70SECh. 15 - Prob. 71SECh. 15 - Prob. 72SECh. 15 - Prob. 74SECh. 15 - Prob. 75SECh. 15 - Prob. 76SECh. 15 - Prob. 77SECh. 15 - Prob. 78SE
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- Annie is concerned over a report that "a woman over age 4040 has a better chance of being killed by a terrorist than of getting married." A study found that the likelihood of marriage for a never-previously-wed, 4040-year-old university-educated American woman was 2.9%2.9%. To demonstrate that this percentage is too small, Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 516516 never-previously-wed, university-educated, American women who were single at the beginning of their 4040s and who are now 4545. Of these women, 2121 report now being married. Does this evidence support Annie’s claim, at the 0.100.10 level of significance, that the chances of getting married for this group is greater than 2.9%2.9%? Step 1 of 3 : State the null and alternative hypotheses for the test. Fill in the blank below. H0Ha: p=0.029: p⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯0.029H0: p=0.029Ha: p00000000_0.029 Answer Tablesarrow_forwardAnnie is concerned over a report that "a woman over age 4040 has a better chance of being killed by a terrorist than of getting married." A study found that the likelihood of marriage for a never-previously-wed, 4040-year-old university-educated American woman was 2.9%2.9%. To demonstrate that this percentage is too small, Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 516516 never-previously-wed, university-educated, American women who were single at the beginning of their 4040s and who are now 4545. Of these women, 2121 report now being married. Does this evidence support Annie’s claim, at the 0.100.10 level of significance, that the chances of getting married for this group is greater than 2.9%2.9%? Step 2 of 3 : Compute the value of the test statistic. Round your answer to two decimal places.arrow_forward12. A researcher conducts an independent-measures studycomparing two treatments and reports the t statistic ast(30) 2.085.a. How many individuals participated in the entire study?b. Using a two-tailed test with .05, is there asignificant difference between the two treatments?c. Compute r2 to measure the percentage of varianceaccounted for by the treatment effect.arrow_forward
- The following data on the left have been gathered from a randomized block design. Test for a significant difference in the treatment levels. Establish the hypotheses and reach a conclusion about the null hypothesis. Block. Treatment Level 1. 2 3 1 1.28 1.29 1.29 2. 1.40 1.36 1.35 3. 1.15 1.13 1.19 4 1.16 1.25 1.33arrow_forward1. To determine whether using a cell phone while driving increases the risk of an accident, a researcher examines accident reports to obtain data about the number of accidents in which a driver was talking on a cell phone. A. Is this a randomized experiment or an observational study? B. Assume that the accident reports show that people were more likely to have an accident while talking on a cell phone. Could this result be due to confounding?arrow_forwardAnnie is concerned over a report that "a woman over age 4040 has a better chance of being killed by a terrorist than of getting married." A study found that the likelihood of marriage for a never-previously-wed, 4040-year-old university-educated American woman was 2.8%2.8%. To demonstrate that this percentage is too small, Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 513513 never-previously-wed, university-educated, American women who were single at the beginning of their 4040s and who are now 4545. Of these women, 2323 report now being married. Does this evidence support Annie’s claim, at the 0.050.05 level of significance, that the chances of getting married for this group is greater than 2.8%2.8%? Step 3 of 3 : Draw a conclusion and interpret the decision.arrow_forward
- Annie is concerned over a report that "a woman over age 4040 has a better chance of being killed by a terrorist than of getting married." A study found that the likelihood of marriage for a never-previously-wed, 4040-year-old university-educated American woman was 3.1%3.1%. To demonstrate that this percentage is too small, Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 465465 never-previously-wed, university-educated, American women who were single at the beginning of their 4040s and who are now 4545. Of these women, 2222 report now being married. Does this evidence support Annie’s claim, at the 0.050.05 level of significance, that the chances of getting married for this group is greater than 3.1%3.1%? Step 2 of 3 : Compute the value of the test statistic. Round your answer to two decimal places. step 3of 3 : Conclusion - Reject the null hypothesis/ fail to reject ...insufficient/sufficientarrow_forwardIn a survey of 460 drivers from the South, 397 wear a seat belt. In a survey of 340 drivers from the Northeast, 281 wear a seat belt. At alpha equals 0.06 , can you support the claim that the proportion of drivers who wear seat belts is greater in the South than in the Northeast? Assume the random samples are independent. Complete parts (a) through (e).arrow_forwardDetermine whether each of the following experiments/situations involve a discrete or a continuous random variable. 4. getting the distance travelled by a car5. the number of phone calls taken by a call center agent in a weekName two random variables of interest in the following studies. 6. An education researcher wishes to see whether or not there is a correlation between the number of hours of sleep of senior high school students and their test scores.____________________ and ____________________ 7. A nurse at the Neonatal Intensive Care Unit (NICU) of St. Mark’s Hospital wishes to explore the relationship between a mother’s age and her baby’s general health.____________________ and ____________________arrow_forward
- Recent incidents of food contamination have caused great concern among consumers. The article “How Safe Is That Chicken?” (Consumer Reports, Jan. 2010: 19–23) reported that 35 of 80 randomly selected Perdue brand broilers tested positively for either campylobacter or salmonella (or both), the leading bacterial causes of food-borne disease, whereas 66 of 80 Tyson brand broilers tested positive. If the true proportions of non-contaminated chickens for the Perdue and Tyson brands are .50 and .25, respectively, how likely is it that the null hypothesis of equal proportions will be rejected when a .01 significance level is used and the sample sizes are both 80?arrow_forwardwhat is the critical value of a single sample t-test based on n=23, and a two-tailed alpha of a=0.05arrow_forwardAn article from the American Journal of Public Health reports the results from a randomized study designed to evaluate the efficacy of an intervention targeted to Hispanic/Latino men who identify as gay, bi-sexual or other men who have sex with men (MSM). A representative sample of 254 such men was randomized to be in either the intervention group (n=152, with 141 ultimately participating in the study) or the control group (n=152, with 147 ulitmately participating in the study). The primary outcome under study getting tested for HIV within the six-months following group assignment (randomization) among those who had been sexually active in this same six-month follow-up period. At six months of follow-up, 141 subjects in the intervention group reported having had sex (with men and/or women) since randomization. Of these 141 men, 114 had been tested for HIV since being randomized. At six months of follow-up, 147 subjects in the control group reported having had sex (with men…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL
Holt Mcdougal Larson Pre-algebra: Student Edition...
Algebra
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL
Hypothesis Testing using Confidence Interval Approach; Author: BUM2413 Applied Statistics UMP;https://www.youtube.com/watch?v=Hq1l3e9pLyY;License: Standard YouTube License, CC-BY
Hypothesis Testing - Difference of Two Means - Student's -Distribution & Normal Distribution; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=UcZwyzwWU7o;License: Standard Youtube License