Question

b and c goes to question 1 PLEASE ANSWER ALL Suppose that I construct a confidence...

b and c goes to question 1 PLEASE ANSWER ALL

  1. Suppose that I construct a confidence interval for the mean test grade on paper 1 using Statcrunch and get Upper Limit, 68.9 and a lower limit 76.3. State the conclusion for the confidence interval.
  2. b)What happens to the confidence interval as we increase the sample size? Explain your reasoning (explanations without reasoning will not be given credit.)
  3. c)When should we use the t-distribution instead of the z-distribution?

Homework Answers

Answer #1

b. The margin of error for confidence interval of mean is . The width of the confidence interval is twice the margin of error. n is the Sample size. So clearly if we increase the sample size then the margin of error will decrease. And also the width of the confidence interval will decrease.

So if we increase sample size the width of the confidence interval will decrease.

c. We should use t distribution when we don't know about the population standard deviation . Then we estimate the population standard deviation by sample standard deviation and use t distribution instead of z distribution to find the critical value.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Question 2: Confidence Intervals Suppose you are a fourth-grade teacher. Your students have all gone trick-or-treating...
Question 2: Confidence Intervals Suppose you are a fourth-grade teacher. Your students have all gone trick-or-treating for Halloween. You had them keep track of how many pieces of candy they collected in the first hour of trick-or-treating. You know that the amount of candy that a student receives is Normally distributed. On average, the 100 students in the fourth grade had 48 pieces of candy. a. Assume that you know σ2 = 81 pieces of candy squared, construct a 90...
Is there a relationship between confidence intervals and two-tailed hypothesis tests? Let c be the level...
Is there a relationship between confidence intervals and two-tailed hypothesis tests? Let c be the level of confidence used to construct a confidence interval from sample data. Let α be the level of significance for a two-tailed hypothesis test. The following statement applies to hypothesis tests of the mean. For a two-tailed hypothesis test with level of significance α and null hypothesis H0: μ = k, we reject H0 whenever k falls outside the c = 1 –  α confidence interval...
1. Assume that we want to construct a confidence interval. Do one of the​ following, as​...
1. Assume that we want to construct a confidence interval. Do one of the​ following, as​ appropriate: (a) find the critical value t Subscript alpha divided by 2​, ​(b) find the critical value z Subscript alpha divided by 2​, or​ (c) state that neither the normal distribution nor the t distribution applies. Here are summary statistics for randomly selected weights of newborn​ girls: n=181​, x= 33.7 ​hg, s= 7.6 hg. The confidence level is 99​%. a. tα/2e= B. za/2 =...
DO NOT RESPOND UNLESS YOU INTEND TO ANSWER EACH QUESTION 1. A university dean is interested...
DO NOT RESPOND UNLESS YOU INTEND TO ANSWER EACH QUESTION 1. A university dean is interested in determining the proportion of students who receive some sort of financial aid. Rather than examine the records for all students, the dean randomly selects 200 students and finds that 118 of them are receiving financial aid. The 95% confidence interval for p is 0.59 ± 0.07. Interpret this interval. a. We are 95% confident that the true proportion of all students receiving financial...
I need someone to answer this question for me please its for Statistical Modeling and Data...
I need someone to answer this question for me please its for Statistical Modeling and Data Analysis. Thanks. 1.      (65 points) Waiting at an ER. A hospital administrator hoping to improve wait times decides to estimate the average emergency room waiting time at her hospital. She collects a simple random sample of 64 patients and determines the time (in minutes) between when they checked in to the ER until they were first seen by a doctor. She repeats this 1000...
Do all the following problems. I. Choose the best answer for each multiple choice. Please use...
Do all the following problems. I. Choose the best answer for each multiple choice. Please use CAPITAL letters to indicate your answer and write neatly. (30 points) 1. ____ 4.____ 7. ____ 10.____ 13. ____ 2. ____ 5.____ 8. ____ 11.____ 14. ____ 3. ____ 6.____ 9. ____ 12.____ 15. ____ Whenever the population standard deviation is unknown and the population has a normal or near-normal distribution, which distribution is used in developing an interval estimation? A. standard distribution B....
Is there a relationship between confidence intervals and two-tailed hypothesis tests? Let c be the level...
Is there a relationship between confidence intervals and two-tailed hypothesis tests? Let c be the level of confidence used to construct a confidence interval from sample data. Let α be the level of significance for a two-tailed hypothesis test. The following statement applies to hypothesis tests of the mean. For a two-tailed hypothesis test with level of significance α and null hypothesis H0: μ = k, we reject H0 whenever k falls outside the c = 1 – α confidence...
Is there a relationship between confidence intervals and two-tailed hypothesis tests? Let c be the level...
Is there a relationship between confidence intervals and two-tailed hypothesis tests? Let c be the level of confidence used to construct a confidence interval from sample data. Let α be the level of significance for a two-tailed hypothesis test. The following statement applies to hypothesis tests of the mean. For a two-tailed hypothesis test with level of significance α and null hypothesis H0: μ = k, we reject H0 whenever k falls outside the c = 1 − α confidence...
Answer the question. CHAPTER 8: ESTIMATION AND CONFIDENCE INTERVALS 1. As degrees of freedom increase, the...
Answer the question. CHAPTER 8: ESTIMATION AND CONFIDENCE INTERVALS 1. As degrees of freedom increase, the t-distribution approaches the: A. binomial distribution B. exponential distribution C. standard normal distribution D. None of the above 2. Given a t-distribution with 14 degrees of freedom, the area left of - 1.761 is A. 0.025 B. 0.05 C. 0.10 D. 0.90 E. None of the above 3. 100 samples of size fifty were taken from a population with population mean 72. The sample...
Part B The situation is as follows: With the cost of attendance rising, BYU administrators are...
Part B The situation is as follows: With the cost of attendance rising, BYU administrators are worried that BYU students are graduating with more and more debt. In a random sample of 312 BYU undergraduate students who graduated in April 2019, 145 of them reported having student debt. Calculate a 98% confidence interval estimate for the proportion of BYU undergraduate students who graduated in April 2019 who have student debt. SHOW YOUR WORK IN ALL THE STEPS. ANSWERS WITHOUT SOLUTIONS...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT