This question is from ex 1418 in the Practice of Statistics

This question is from ex 14.18 in the Practice of Statistics in Life Sciences 3rd but the answer isn\'t posted yet on the site

.Hepatitis C and bone density. Does chronic hepatitis C infection impact bone mineral density? In the general population of young healthy adults, bone mineral denisty is Normally distributed, and density scores are standardized to have a mean u= 0 and a standard deviation of =1. A study examined the bone densities of random sample of 28 adult men suffering from chronic hepatitis C infection. Their mean standardized bone density was -0.61. Does this provide good evidence that the mean standardized bone density of adult men suffering from Hepatitis C infection is less than 0?

Solution

Sol)

H0:  u= 0

H1:  u<0 (Left tail)

Level of significance is 5%

Test statistic is -0.67

Conclusion: t cal =-0.67 and t critical value is -1.703 at 5% level with 27 d.f

Hence t cal < t critical value , we accept the null hypothesis.

Hence the mean standardized bone density of adult men suffering from Hepatitis C infection is0.