Question

Does secondhand smoke increase the risk of a low weight birth? a baby is "low birth weight" if it weighs less than 5. 5 pounds at birth. According to the national center of health statistics, about 7. 8% of all babies born in the u. S. Are categorized as low birth weight. Researchers randomly select 1200 babies whose mothers had extensive exposure to secondhand smoke during pregnancy. 10. 4% of the sample are categorized as low birth weight. Which of the following are the appropriate null and alternative hypotheses for this research question.

Answer 1

The appropriate null and alternative hypotheses for this research question are:

Null Hypothesis: Secondhand smoke exposure during pregnancy does not increase the risk of having a low birth weight baby.

Alternative Hypothesis: Secondhand smoke exposure during pregnancy increases the risk of having a low birth weight baby.

In statistical terms, the null hypothesis can be represented as:

H0: p = 0.078

Where p is the proportion of low birth weight babies in the general population (based on the national center of health statistics).

The alternative hypothesis can be represented as:

Ha: p > 0.078

Where p is the proportion of low birth weight babies in the sample of babies whose mothers had extensive exposure to secondhand smoke during pregnancy.

Note that the alternative hypothesis is one-tailed, as we are only interested in whether the proportion of low birth weight babies in the sample is greater than the proportion in the general population.