An article in Journal of Structural Engineering presents the results of an experiment that evaluated a...

An article in Journal of Structural Engineering presents the results of an experiment that evaluated a standard method for estimating the brace force for a truss. In a sample of 360 short test trusses the method underestimated the force for 45 of them, and in a sample of 400 long test trusses, the method underestimated the force for 60 of them. Find a 95% confidence interval for the difference between the underestimation rates for long and short trusses.

Solutions

Expert Solution

Population 1 = long test trusses

Population 2 = short test trusses

Therefore, based on the data provided,95% confidence interval for the difference between the underestimation rates for long and short trusses. p1−p2 is −0.024<p<0.074, which indicates that we are 95% confident that the true difference between population proportions is contained by the interval (-0.024, 0.074)

orchestra answered 1 year ago

Next > < Previous

Related Solutions

1. An article from an Environmental Engineering journal reported the results of a study on the...

1. An article from an Environmental Engineering journal reported the results of a study on the occurrence of sodium and chloride on the surface of water currents in Rhode Island. The following data presents the concentration of chloride designated ? (in milligrams per liter) and the taxiway area in the basin as ? (in percentage). ? 4.4 6.6 9.7 10.6 10.8 10.9 ? 0.19 0.15 0.57 0.70 0.67 0.63 ? 11.8 12.1 14.3 14.7 15.0 17.3 ? 0.47 0.70 0.60...

summarize and analyze a peer-reviewed journal article that presents qualitative research results (effective communication and adapting...

summarize and analyze a peer-reviewed journal article that presents qualitative research results (effective communication and adapting to change within workplace scenarios). Are there any key insights from the qualitative article.

An article in the Journal of Environmental Engineering (1989, Vol. 115(3), pp. 608–619) reported the results...

An article in the Journal of Environmental Engineering (1989, Vol. 115(3), pp. 608–619) reported the results of a study on the occurrence of sodium and chloride in surface streams in central Rhode Island. The following data are chloride concentration y (in milligrams per liter) and roadway area in the watershed x (in percentage). (5px5) Y: 4.4 6.6 9.7 10.6 10.8 10.9 11.8 12.1 14.3 14.7 15.0 17.3 19.2 23.1 27.4 27.7 31.8 39.5 X: 0.19 0.15 0.57 0.70 0.67 0.63...

You read in the results section of an article in a psychology journal that the results...

You read in the results section of an article in a psychology journal that the results of at-test for independent sample means revealed a significant t12 = 1.8, with σˆX1−X2 = 2. If there were 8 participants in the experimental group, (a) how many participants were in the corresponding control group? (b) what significance level was used, and was the test a one-tailed or a two-tailed test? (c) what was the mean difference between the experimental and the control groups?

Structural engineering

The results of a tensile test can be evaluated as either engineering stress-strain curves or true...

The results of a tensile test can be evaluated as either engineering stress-strain curves or true stress-strain curves. The original cross-sectional area of the tensile test specimen is used to plot the former one, whereas the instantaneous cross-sectional area is used for the latter one. Assume that you are an engineer who needs to design a structural product using a hypothetical metal A, which should not plastically deform in the application area. You need to apply a tensile test to...

An article presents the results of a study in which the weights of 295 eggs from...

An article presents the results of a study in which the weights of 295 eggs from 27-week-old breeding hens averaged 54.1 g with a standard deviation of 4.4 g, and weights of 295 eggs from 59-week-old hens averaged 72.7 g with a standard deviation of 4.7 g. Let μX represent the population mean weight for 59-week-old hens and let μY represent the population mean weight for 27-week-old hens. Find a 95% confidence interval for the difference μX−μY . Round the...

An article in the Journal of the American Medical Assocation described an experiment to investigate the...

An article in the Journal of the American Medical Assocation described an experiment to investigate the effect of four treatments on various body characteristics. In this double-blind experiment, each of 59 female subjects age 65 or older was assigned at random to one of the following four treatments: 1) P + P: placebo "growth hormone" and placebo "steroid" 2) P + S: placebo "growth hormone" and the steroid estradiol 3) G + P: growth hormone and placebo "steroid" 4) G...

Find the original published journal article for the Griffith experiment and the Hershey Chase experiment. Put...

Find the original published journal article for the Griffith experiment and the Hershey Chase experiment. Put the citations here:

An article in Optical Engineering reported on use of an optical correlator to perform an experiment...

An article in Optical Engineering reported on use of an optical correlator to perform an experiment by varying brightness and contrast. The useful range of gray levels characterizes the resulting modulation. The data are shown below: Brightness (%): 54 61 65 100 100 100 50 57 54 Contrast (%): 56 80 70 50 65 80 25 35 26 Useful range (ng): 96 50 50 112 96 80 155 144 255 USING MINITAB... Fit a multiple linear regression model to these...

Subjects