Question

7. Psychological and social factors can influence the survival of patients with serious diseases. One study compared the relationship between survival of patients with coronary heart disease and pet ownership. Patients were either classified as having a pet or not and whether they survived for 1 year. Based on the data below, is there an association between owning a pet and survival? No need to do the entire significance test, just the parts below. Pet Ownership Patient Status Yes No Alive 28 50 Dead 11 3 a. State the hypotheses for the appropriate test in the context of this problern. + b. If the X test statistie has a value of 8 85 then give the p-value and conclusion of your significance test. 8. A researcher wishes to determine whether the rate of water flow (x) in liters per second) over an experimental soil bed can be used to predict the amount of soil washed awayçy) (in kilograms). The researcher measures the amount of soil washed away for various flow rates, finds that the sample mean flow rate is 6.1 Lis with a standard deviation of 0.5 Ls. Also the sample mean for the amount of creded soil is 4.2 kg with a standard deviation of 1.2 kg. If the correlation between flow rate (s) and the amount of eroded soil (9) is 0.65 then give The equation of the least squares regression line of yonx b What is the predieted amount of eroded soil for a flow rate of 108?

Answer 1

a)

The following null and alternative hypotheses need to be tested: Ho: The two variables are independent H: The two variables are dependent

b)

df = (2-1) x (2-1) = 1

using below function in excel

p = CHIDIST (X2, v)

p-value = 0.00293

we are allowed to solve one question only.