Antibiotics in Infancy
Exercise 2.19 describes a Canadian longitudinal study that examines whether giving antibiotics in infancy increases the likelihood that the child will be overweight later in life. The study included 616 children and found that 438 of the children had received antibiotics during the first year of life. Test to see if this provides evidence that more than 70% of Canadian children receive antibiotics during the first year of life.
(a) State the null and alternative hypotheses
(b) Calculate the z-statistic.
(c) Find the p-value.
(d) Make a generic conclusion about the null hypothesis, using α = 0.05
(e) Make a conclusion in context.

Respuesta :

Answer:

e)The information from the sample does not give enough information  to support that more than 70% of Canadian children receive antibiotics during the first year of life

Step-by-step explanation:

The proportion we will use for the test is  p  = 70 %

From a random sample we got

n  =  616

x = 438      then   p₁ = 438/616     p₁  =  0,71    p₁  = 71 %

Then  q₁  =  1 - p₁      q₁  = 1 - 0,71    q₁ = 0,29   q₁ = 29 %

a) Hypothesis test:

Null hypothesis                      H₀           p₁   = p

Alternative hypothesis          Hₐ           p₁  > p >70 %

CI = 95 % significance level    α  = 5 %   α = 0,05

z(c) for  α  =  0,05   from z-table is    z(c)  = 1,64

b) To calculate  z(s)  =  ( p₁  -  p ) / √ p₁*q₁ / n

z(s) = ( 0,71  -  0,70 )/ √ 0,71*0,29/616

z(s) = 0,01 /0,01828

z(s) = 0,547 ≈ 0,55

c) p-value for   z(s) is from z-table   p-value ≈ 0,7088

d) p-value > 0,05   then we accept H₀  we don´t have enough evidence to reject H₀

e)The information from the sample does not give enough information  to support that more than 70% of Canadian children receive antibiotics during the first year of life