Question

Background: Based on the National Center of Health Statistics, the proportion of babies born at low birth weight (below 2,500 grams) in the United States is roughly .078, or 7.8% (based on all the births in the United States in the year 2002). A study was done in order to check whether pregnant women exposed to second hand smoke increases the risk of low birth weight. In other words, the researchers wanted to check whether the proportion of babies born at low birth weight among women who were exposed to second hand smoke during their pregnancy is higher than the proportion in the general population. The researchers followed a sample of 400 women who had been exposed regularly to second hand smoke during their pregnancy and recorded the birth weight of the newborns. Based on the data, the p-value was found to be .119.1.Based on the p-value, what is your conclusion (use .05 significance level)?

Answer 1

Explanation:

Hello!

Remember, the rule to decide using the p-value is always the same.

If the p-value ≤ α, you reject the null hypothesis.

If the p-value > α, you support the null hypothesis.

The experiment states the hypothesis that the proportion of babies born with low weight is higher if their mothers were exposed to second-hand smoking during pregnancy. Symbolically:

H₀: ρ ≤ 0.078

H₁: ρ > 0.078

α: 0.05

The given p-value is 0.119

Since the p-value (0.119) is greater than the level of significance (α: 0.05) the decision is to not reject the null hypothesis.

The proportion of babies born with low weight among women that were exposed to second-hand smoking during pregnancy is no different from the proportion in the general population.

I hope it helps!