Question

In a study published in 2007 by the NCBI and National Institutes of Health (NIH) under their OpenMed initiative, researchers wanted to determine if there were "differences between ethnic groups with respect to fetal growth." In particular, were infants of European descent heavier at birth than infants of Chinese descent?

a) What hypotheses are they testing?

H₀: μ_Euro - μ_Chinese = 0 vs. H_a: μ_Euro - μ_Chinese > 0H₀: p_Euro - p_Chinese = 0 vs. H_a: p_Euro - p_Chinese ≠ 0    H₀: μ_D = 0 vs. H_a: μ_D > 0

b) The researchers reported for their test a p-value of 0.001. What should they conclude at α = .05?

Newborn European infants weigh more, on average, than newborn Chinese infants.There is not enough evidence to conclude that newborn European infants weigh more, on average, than newborn Chinese infants.    Newborn European infants and newborn Chinese infants do not have significantly different weights.Ethnicity and weight at birth are independent.

Answer 1

a) The hypotheses they are testing is:

H₀: μ_Euro - μ_Chinese = 0 vs. H_a: μ_Euro - μ_Chinese > 0

Option A is correct.

b) Option A is correct.