1. Which of the following statements are true? When generating confidence interv

Question

1. Which of the following statements are true?

When generating confidence intervals and when doing significance tests we use the same expression for the standard error.

If zero is in the confidence interval for the difference between two proportions, we have evidence that the two population proportions could be the same.

When we do a significance test for the difference between two proportions, we're justified in pooling our estimates of the population proportion only if the sample sizes are large.

options:

I only

II only

III only

II and III only

I and III only

2.A company manufactures bolts to be used in missile defense operations. Because of the product’s intended use, the manufacturer needs a 99% confidence interval for the population defect rate. The allowable error is 1%, and the current defect rate is 1%. How many bolts does the manufacturer need to sample to make sure it is meeting its manufacturing standards?

options:

3.In a televised game show, contestants are asked to pick what is behind Door #1, Door #2, Door #3, and Door #4. The only difference the contestant can see is the number on the door. If contestants do not have a preference for particular numbers, then each door should have a 25% chance of being selected. The game producers, however, have decided to analyze the contestant’s choices to see if they have a preference for certain doors, so they gathered the following data on door choices: out of 160 trials, contestants made the following choices: Door #1 was selected 38 times; Door #2 was selected 42 times; Door #3 was selected 42 times; Door number 4 was selected 38 times.   What is the Chi Square statistic in this example?

options:

I only

II only

III only

II and III only

I and III only

2.A company manufactures bolts to be used in missile defense operations. Because of the product’s intended use, the manufacturer needs a 99% confidence interval for the population defect rate. The allowable error is 1%, and the current defect rate is 1%. How many bolts does the manufacturer need to sample to make sure it is meeting its manufacturing standards?

options:

a) 650 b) 659 c) 380 d) 381 e) None of the above

3.In a televised game show, contestants are asked to pick what is behind Door #1, Door #2, Door #3, and Door #4. The only difference the contestant can see is the number on the door. If contestants do not have a preference for particular numbers, then each door should have a 25% chance of being selected. The game producers, however, have decided to analyze the contestant’s choices to see if they have a preference for certain doors, so they gathered the following data on door choices: out of 160 trials, contestants made the following choices: Door #1 was selected 38 times; Door #2 was selected 42 times; Door #3 was selected 42 times; Door number 4 was selected 38 times.   What is the Chi Square statistic in this example?

options:

a) 0.04 b) 0.4 c) 4 d) 40 e) None of the above

Explanation / Answer

1. Which of the following statements are true?

When generating confidence intervals and when doing significance tests we use the same expression for the standard error.

If zero is in the confidence interval for the difference between two proportions, we have evidence that the two population proportions could be the same.

When we do a significance test for the difference between two proportions, we're justified in pooling our estimates of the population proportion only if the sample sizes are large.

Answer : I only

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.