Question

Meet our dog; Otter; three-year old lab-shepherd mix. Unfortunately, Otter has cancer in her right front leg which will eventually affect her lungs. Vets have suggested two courses of action. Medicate her and keep her comfortable until she dies or amputate the leg with the hopes of extending her life. The following table shows paired differences of life expectancy of seven dogs close to two-years old with this specific type of osteo sarcoma. Each of the owners will make their decision based on the data in the table below. Test the veterinarian’s claim that the average dog will increase his or her life by removing the affected leg. α = 0.10; ∑D = -4.75; SD = .40,

• A. 1 tail, 1.415, 28.28

• B. -1.440, -4.48, R Ho

• C. 1 tail, 1.440, 1.41, R H

• D. 1 tail, 1.440, -1.41

• E. 1 tail, -1.895, -4.48, R Ho

Answer 1

Answer: E. 1 tail, -1.895, -4.48, R Ho

H0: The average dog will not increase his or her life by removing the affected leg. i.e D = 0

H1: The average dog will increase his or her life by removing the affected leg. i.e D < 0

Paired t test

Test statistics:

t = -4.488

critical value = -1.95 (from statistical table)

conclusion

t value < critical value. Hence the value falls in rejection region. So we conclude that the null hypothesis H0 is rejected.