A study of iron deficiency among infants compared samples of infants following d
ID: 3374874 • Letter: A
Question
A study of iron deficiency among infants compared samples of infants following different feeding regimens. One group contained breast-fed infants, while the children in another group were fed a standard baby formula without any iron supplements. Here are summary results on blood hemoglobin levels at 12 months of age. Groupnxs Breast-fed 23 13.2 1.7 Formula20 12.4 1.8 (a) Is there significant evidence that the mean hemoglobin level is higher among breast-fed babies? State Ho and Ha O HO-Abreast-fed > ?formulai Ha: Abreast-fed-lformula Carry out a t test. Give the P-value. (Use ? = 0.01. Use ?breast-fed-lformula. Round your value for t to three decimal places, and round your P-value to four decimal places.) P-value What is your conclusion? O Reject the null hypothesis. There is significant evidence that the mean hemoglobin level is higher among breast-fed babies O Reject the null hypothesis. There is not significant evidence that the mean hemoglobin level is higher among breast-fed babies. Fail to reject the null hypothesis. There is not significant evidence that the mean hemoglobin level is higher among breast-fed babies. Fail to reject the null hypothesis. There is significant evidence that the mean hemoglobin level is higher among breast-fed babies. (b) Give a 95% confidence interval for the mean difference in hemoglobin level between the two populations of infants. (Round your answers to three decimal places.)Explanation / Answer
The statistical software output for this problem is:
Two sample T summary hypothesis test:
?1 : Mean of Population 1
?2 : Mean of Population 2
?1 - ?2 : Difference between two means
H0 : ?1 - ?2 = 0
HA : ?1 - ?2 > 0
(with pooled variances)
Hypothesis test results:
95% confidence interval results:
Hence,
t = 1.498
P-value = 0.0709
95% confidence interval: (-0.279, 1.879)
Difference Sample Diff. Std. Err. DF T-Stat P-value ?1 - ?2 0.8 0.53414782 41 1.4977128 0.0709Related Questions
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