| Previous AnswersDevoreStat9 9.E.006.
Ask Your Teacher
My Notes
Question Part |
Points |
Submissions Used |
An experiment to compare the tension bond strength of polymer
latex modified mortar (Portland cement mortar to which polymer
latex emulsions have been added during mixing) to that of
unmodified mortar resulted in x = 18.17 kgf/cm2
for the modified mortar (m = 42) and y = 16.85
kgf/cm2for the unmodified mortar (n = 32). Let
μ1 and μ2 be the true
average tension bond strengths for the modified and unmodified
mortars, respectively. Assume that the bond strength distributions
are both normal.(a) Assuming that σ1 = 1.6 and
σ2 = 1.3, test H0:
μ1 − μ2 = 0 versus
Ha: μ1 −
μ2 > 0 at level 0.01.
Calculate the test statistic and determine the P-value.
(Round your test statistic to two decimal places and your
P-value to four decimal places.)
z | = | |
P-value | = |
State the conclusion in the problem context.
Reject H0. The data does not suggest that the difference in average tension bond strengths exceeds 0.Fail to reject H0. The data does not suggest that the difference in average tension bond strengths exceeds from 0. Reject H0. The data suggests that the difference in average tension bond strengths exceeds 0.Fail to reject H0. The data suggests that the difference in average tension bond strengths exceeds 0.
(b) Compute the probability of a type II error for the test of part
(a) when μ1 − μ2 = 1.
(Round your answer to four decimal places.)
(c) Suppose the investigator decided to use a level 0.05 test and
wished β = 0.10 when μ1 −
μ2 = 1. If m = 42, what value of
n is necessary? (Round your answer up to the nearest whole
number.)
n =
(d) How would the analysis and conclusion of part (a) change if
σ1 and σ2 were unknown but
s1 = 1.6 and s2 = 1.3?
Since n = 32 is not a large sample, it would no longer be appropriate to use the large sample test. A small sample t procedure should be used, and the appropriate conclusion would follow.Since n = 32 is a large sample, it would no longer be appropriate to use the large sample test. Any other test can be used, and the conclusions would stay the same. Since n = 32 is a large sample, it would be more appropriate to use the t procedure. The appropriate conclusion would follow.Since n = 32 is not a large sample, it still be appropriate to use the large sample test. The analysis and conclusions would stay the same.
| Previous AnswersDevoreStat9 9.E.006. Ask Your Teacher My Notes Question Part Points Submissions Used An experiment to co...
An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.18 kgf/cm2 for the modified mortar (m = 42) and y = 16.88 kgf/cm2 for the unmodified mortar (n = 30). Let uz and uz be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions...
An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.11 kgf/cm2 for the modified mortar (m = 42) and y = 16.84 kgf/cm2 for the unmodified mortar (n = 30). Let uy and My be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions...
An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.19 kgf/cm2 for the modified mortar (m = 42) and y = 16.87 kgf/cm2 for the unmodified mortar (n = 31). Let Hy and uz be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions...
An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.13 kgf/cm2 for the modified mortar (m = 42) and y = 16.83 kgf/cm2 for the unmodified mortar (n = 32). Let μ1 and μ2 be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions...
strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during miing) to that o unmodified mortar resulted in x 18.16 kgt/cm2 for the modified mortar (m 42) and y tension bond strengths for the modified and unmodified -16.87 kgf/cm2 for the unm dined mortar (n = 30). Let μ1 and», be the true average mortars, respectively. Assume that the bond strength distributions are both normal. (a) Assuming that σ1 1.6 and σ2-1.3,...
1. An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in =18.12 kgf/cm2 for the modified mortar (m=40) and j = 16.87 kgf/cm2 for the unmodified mortar (n=32). Let Hy and My be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions are both normal. a. Assuming...
An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.12 kgf/cm2 for the modified mortar (m = 40) and y = 16.87 kgf/cm2 for the unmodified mortar (n = 32). Let ?1 and ?2 be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions...
============================================== An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in 3 = 18.14 kgf/cm2 for the modified mortar (m = 42) and y = 16.34 kgf/cm2 for the unmodified mortar (n = 32). Let u, and uz be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength...
An experiment was performed to compare the fracture toughness of high-purity 18 Ni maraging steel with commercial-purity steel of the same type. For m = 30 specimens, the sample average toughness was x = 65.5 for the high-purity steel, whereas for n = 39 specimens of commercial steel y = 59.9. Because the high-purity steel is more expensive, its use for a certain application can be justified only if its fracture toughness exceeds that of commercial-purity steel by more than...
Would Not Approve of Driving Drunk Would Not Approve of Driving Drunk n1=40 n2=25 X¯1=2.1 X¯2=8.2 s1=1.8 s2=1.9 John Worrall and colleagues (2014) found that the fear of losing the good opinion of one’s family and peers kept people from driving home drunk. Let’s say we have two independent random samples of people: those who think that their peers would disapprove of them from driving drunk, and those who think that their peers would either not care or approve of...