Can someone please confirm that all of my answers are correct and if not, which
ID: 3129931 • Letter: C
Question
Can someone please confirm that all of my answers are correct and if not, which ones are wrong and why?!!! PLEASE HELP
1) Hemoglobin is a protein in the red blood cells that carries oxygen from the lungs to body tissues. People with less than 12 grams of hemoglobin per deciliter of blood (g/dl) are anemic. One public health official in Jordan tested whether the mean hemoglobin level for all children is less than 12 grams. He took a random sample of 50 children, found P-value = 0.047 and concluded that the mean hemoglobin level for all children is less than 12 grams at = 0.05. Another public health official performed the same test by taking a different random sample of 50 children and found P-value = 0.052. At = 0.05, she concluded that the mean hemoglobin level for all children is NOT less than 12 grams. What advice would you give those concerned about these controversial results?
a. One of the health officials made a mistake in their analysis.
b. Neither health official's results should be believed.
c. There is no sharp border between significant and not significant, only increasingly strong evidence against the null hypothesis as the P-value decreases.
2) A poultry farmer analyzed the egg production of his 20,000 chickens. When he compared the mean production of eggs per month for the 10,000 chickens living in the north side of his chicken housing with the mean production of eggs per month for the 10,000 chickens living in the south side of his chicken housing, he computed a P-value of 0.0011. Is this difference statistically significant at = 0.05?
a. Yes
b. No
3) Referring to question 4, as the result of his analysis, the poultry farmer considered building more housing units so that all chickens could live on the north side since the mean egg production for all chickens living on the north side was higher by 1 egg per month than for all chickens living on the south side. On the basis of this difference between the means of 1 egg per month, are these results practically significant?
a. Yes
b. No
4) True or false: Data should always be plotted and examined for outliers when doing inference, especially when sample sizes are small.
a. True
b. False
5) Which of the following does the researcher NOT control?
a. The population standard deviation.
b. The sample size.
c. The level of confidence.
5) When performing a test of significance, when should we select ?
a. In the PLAN step when defining the research problem.
b. In the SOLVE step after collecting data, but before graphing and computing numerical summaries.
c. In the SOLVE step after graphing and computing numerical summaries, but before computing P-value.
d. In the SOLVE step after computing P-value.
e. In the CONCLUSION step before comparing with P-value.
6) Statistical inference depends on all of the following except one. Which one is NOT something upon which statistical inference depends?
a. the laws of probability and chance
b. properly collected data
c. data from a convenience sample
d. sampling distribution of the statistic
e. a parameter to be estimated or tested
7) The test statistic for testing H0: = 45 versus Ha: < 45 is z = -1.86 and the associated P-value is 0.0314. What would be the P-value for testing H0: = 45 versus Ha: 45 for the same test statistic?
a. 0.0157
b. 0.0314
c. 0.0628
d. 0.9686
e. 1.9372
8) True or false: If a small random sample has a lot of chance variation, a test of significance may fail to find a large population effect to be significant.
a. True
b. False
9) Company executives are concerned that their bags of chips were being overfilled. They decide to take a sample of bags to estimate , the mean weight of their bags. They want to estimate this with 95% confidence and they want their estimate to be within ± 0.5 oz of . They know from previous studies that the population standard deviation, , is equal to 2.4 oz. How many bags should they sample?
a. 0.5
b. 2.4
c. 9
d. 89
10) Referring to the above question, suppose the company's statisticians came back to tell the executives that they should estimate with 99% confidence and not 95%. What effect would this have on the required sample size, n?
a. It would decrease n.
b. It would have no effect on n.
c. It would increase n.
11) Referring to the above two questions, suppose the company's executives decided they needed to estimate the mean weight to within ±0.2 oz rather than within ±0.5 oz. What effect would this have on the required size, n?
a. It would decrease n.
b. It would have no effect on n.
c. It would increase n.
Explanation / Answer
6) Statistical inference depends on all of the following except one. Which one is NOT something upon which statistical inference depends?
c. data from a convenience sample
7) The test statistic for testing H0: = 45 versus Ha: < 45 is z = -1.86 and the associated P-value is 0.0314. What would be the P-value for testing H0: = 45 versus Ha: 45 for the same test statistic?
p value will be 0.0314*2 = 0.0628
c. 0.0628
8) True or false: If a small random sample has a lot of chance variation, a test of significance may fail to find a large population effect to be significant.
a. True
9) Company executives are concerned that their bags of chips were being overfilled. They decide to take a sample of bags to estimate , the mean weight of their bags. They want to estimate this with 95% confidence and they want their estimate to be within ± 0.5 oz of . They know from previous studies that the population standard deviation, , is equal to 2.4 oz. How many bags should they sample?
n = [1.96*2.4 / 0.5] ^2 = 88.51
= 89
d. 89
10) Referring to the above question, suppose the company's statisticians came back to tell the executives that they should estimate with 99% confidence and not 95%. What effect would this have on the required sample size, n?
c. It would increase n.
11) Referring to the above two questions, suppose the company's executives decided they needed to estimate the mean weight to within ±0.2 oz rather than within ±0.5 oz. What effect would this have on the required size, n?
a. It would decrease n.
for the other quesiton I can gladly help you but please post it in a new question