Question

1.

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.

A. H0: p = 0.078; Ha: p ≠ 0.078

B. H0: p = 0.078; Ha: p > 0.078

C. H0: p = 0.104; Ha: p ≠ 0.104

D. H0: μ = 0.104; Ha: μ > 0.104

2.

Discrimination in the workplace: A large multinational corporation is accused of discriminatory hiring practices, tending to hire male employees who are 25 to 30 years old. After management agree to offer a series of human resource trainings at their various locations, in-house staff examine and analyze their most current hiring data. They look at a sample of 2,000 new employees and find that a higher proportion of female employees have been recently hired, and the difference is statistically significant.

Which of the following best describes how we should interpret these results?

A. With a large sample, statistically significant results suggest a large improvement in perceived discriminatory hiring practices.

B. With a large sample, statistically significant results may actually indicate a small improvement in perceived discriminatory hiring practices.

C. Regardless of the sample size, a statistically significant result means there is a meaningful difference in hiring practices.

Answer 1

The appropriate null and alternative hypothesis for this research is obtained below From the given information, researchers randomly select 1,200 babies whose mothers had extensive exposure to second hand smoke during pregnancy. According to the National Center Health Statistics, about 7.8% of all babies born in the US are categorized as low birth weight The claim of the test all babies born in the US are categorized as low birth weight is 7.8%. Null hypothesis: H p 0.078 Alternative Hypothesis: H p> 0.078 Thus, the correct answer s Ho p 0.078 and H p>0.078

2. From the given information, 2,000 new employees are looked a higher proportion of female employees have been recently hired, and the difference is statistically significant. It is clearly denoted that the test statistics statistically significant. If the test statistics is statistically significant the claim will be rejected. Hence there is sufficient evidence to conclude that the higher proportion of female employees have been recently hired It means the company tend to hire male employees, but it results about the higher proportion of female employees. Hence, the correct answer is with a large sample, statistically significant results may actually indicate a small improvement in perceived discriminatory hiring practices