The article “Effect of Granular Subbase Thickness on Airfield Pavement Structural Response” (K. Gopalakrishnan and M. Thompson, Journal of Materials in Civil Engineering. 2008:331–342) presents a study of the effect of the subbase thickness (in mm) on the amount of surface deflection caused by aircraft landing on an airport runway. Two landing gears, one simulating a Boeing 747 aircraft, and the other a Boeing 777 aircraft, were trafficked across four test sections of runway. The results are presented in the following table.
Can you conclude that the mean deflection is greater for the Boeing 777?
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- Here is a dataset containing plant growth measurements of plants grown in solutions of commonly-found chemicals in roadway runoff.Phragmites australis, a fast-growing non-native grass common to roadsides and disturbed wetlands of Tidewater Virginia, was grown in a greenhouse and watered with either: Distilled water (control); A weak petroleum solution (representing standard roadway runoff); Sodium chloride solution; Magnesium chloride solution; De-icing brine (50% sodium chloride and 50% magnesium chloride).Twenty grass preparations were used for each solution, and total growth (in cm) was recorded after watering every other day for 40 days.-Perform the correct statistical test to determine the p-value.-Report your answer rounded to four decimal places.-You should use formulas, functions, and the Data Analysis ToolPak in MS Excel to avoid additive rounding errors. Here are some useful functions: =t.test(array1,array2,tails,type) Produces a p-value for any…arrow_forwardStressed-Out Bus Drivers. Previous studies have shown that urban bus drivers have an extremely stressful job, and a large proportion of drivers retire prematurely with disabilities due to occupational stress. In the paper, “Hassles on the Job: A Study of a Job Intervention With Urban Bus Drivers” (Journal of Organizational Behavior, Vol. 20, pp. 199–208), G. Evans et al. examined the effects of an intervention program to improve the conditions of urban bus drivers.Amongother variables, the researchers monitored diastolic blood pressure of bus drivers in downtown Stockholm, Sweden. The data, in millimeters of mercury (mm Hg), on the WeissStats site are based on the blood pressures obtained prior to intervention for the 41 bus drivers in the study. Use the technology of your choice to do the following. a. Obtain a normal probability plot, boxplot, histogram, and stemand-leaf diagram of the data. b. Based on your results from part (a), can you reasonably apply the one-mean t-test to the…arrow_forwardThe spike stature of the plants grown from the seeds of the porcine separates (Dactylis glomerata L) collected from the University campus and İbradı Eynif pasture are given below. In this plant, compare whether there is a difference between regions in terms of spike height. Virgo Height (cm) Data obtained from plants collected from university campus 5 6 8 7 8 6 5 5 4 6 6 Data obtained from plants collected from Eynif pasture 12 9 11 9 9 11 9 10 11 10 Note: Your results interpretation according to two different possibilities (Do it separately, assuming that it is 0.07 and 0.04).arrow_forward
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