Question

You have measured the blood hemoglobin concentrations in a random sample of 12 males aged 20-29 years and have obtained the fQUESTION 9 10 points Save Answer What is the lower bound of the 95% confidence interval for the standard deviation of this sa

0 0
Add a comment Improve this question Transcribed image text
Answer #1

14.7 15.22 15.28 16.58 15.1 15.66 15.91 14.41 14.73 15.09 15.62 14.92 15.26833 0.598693 MEAN S.D

SOLUTION 1:SAMPLE MEAN = 15.27
t CRITICAL = 2.2
sM = √(0.5992/12) = 0.17

μ = M ± t(sM)
μ = 15.27 ± 2.2*0.17
μ = 15.27 ± 0.374

Result

M = 15.27, 95% CI [14.89, 15.64].

You can be 95% confident that the population mean (μ) falls between 14.89 and 15.64.

SOLUTION 2: SAMPLE MEAN = 15.27
t CRITICAL VALUE= 3.11
sM = √(0.5992/12) = 0.17
μ = M ± t(sM)
μ = 15.27 ± 3.11*0.17
μ = 15.27 ± 0.53

99% CI [14.74, 15.80].

You can be 99% confident that the population mean (μ) falls between 14.74 and 15.80.

SOLUTION 3: The critical values for α=0.05 and df=11 degrees of freedom are χL2​=χ1−α/2,n−1/2​=3.8157 and χU2​=χα/2,n−1/2​=21.92. The corresponding confidence interval is computed as shown below:

CI(Variance) = (n-1) s x 2,1-1 (n-1)s xi-a 2,n-1 - (0222015 (1303585 (12 - 1) x 0.3584 (12-1) X 0.3584 3.8157 21.92 = (0.1799

Now that we have the limits for the confidence interval, the limits for the 95% confidence interval for the population standard deviation are obtained by simply taking the squared root of the limits of the confidence interval for the variance, so then:

CI(Standard Deviation) = (0.1799, V1.0332) = (0.4241, 1.0165)

SOLUTION 4: The critical values for α=0.01 and df=11 degrees of freedom are χL2​=χ1−α/2,n−1/2​=2.6032 and χU2​=χα/2,n−1/2​=26.7568. The corresponding confidence interval is computed as shown below

Now that we have the limits for the confidence interval, the limits for the 99% confidence interval for the population standard deviation are obtained by simply taking the squared root of the limits of the confidence interval for the variance, so then:

CI(Variance) = ((n − 1)s? (n − 1) s2 ( xa 2.1-1 xi-a/2n-1 ((12-1) x 0.3584 (12-1) x 0.3584 26.7568 2.6032 = (0.1473, 1.5144)

AS PER THE GUIDELINES I HAVE DONE THE FIRST FOUR PLEASE RE POST THE REST. THANK YOU

CI(Standard Deviation) = (v0.1473, 71.5144) = (0.3839, 1.2306)

Add a comment
Know the answer?
Add Answer to:
You have measured the blood hemoglobin concentrations in a random sample of 12 males aged 20-29...
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. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
  • The fitness of 514 adults (aged 25 to 35) were sampled and their heart rates measured...

    The fitness of 514 adults (aged 25 to 35) were sampled and their heart rates measured immediately after exercise. This sample of adults was found to have a mean of 1427 beats (per 10 minutes) with a standard deviation of 325 beats (per 10 minutes). Construct a two-tailed 95% confidence interval for the true mean heart beat of all such adults. Determine the sample size that would be necessary to obtain an interval with width (at most) 50 for a...

  • 5) In a simple random sample of 59 electronic components produced by a certain method, the...

    5) In a simple random sample of 59 electronic components produced by a certain method, the mean lifetime was 1,114 hours. Assume the component lifetimes are normally distributed with population standard deviation 55 hours. What is the upper bound of the 95% confidence interval for the mean lifetime of the components? Round to nearest integer. 6) Efficiency experts study the processes used to manufacture items in order to make them as efficient as possible. One of the steps used to...

  • 2. ㅢ5 points DevoreStat97 E.010 My Notes Ask Your Teacher + A random sample of n-15...

    2. ㅢ5 points DevoreStat97 E.010 My Notes Ask Your Teacher + A random sample of n-15 heat pumps of a certain type yielded the following observations on lifetime (in years): 2.0 1.4 6.0 1.6 5.3 0.4 1.0 5.3 15.8 0.7 4.80.9 12.2 5.3 0.6 (a) Assume that the lifetime distribution is exponential and use an argument parallel to that of this example to obtain a 95% CI for expected (true average) lifetime. (Round your answers to two decimal places.) years...

  • A random sample of n=100 observations produced a mean of x¯=33 with a standard deviation of...

    A random sample of n=100 observations produced a mean of x¯=33 with a standard deviation of s=5. Each bound should be rounded to three decimal places. (a) Find a 95% confidence interval for μ Lower-bound: Upper-bound: (b) Find a 99% confidence interval for μ Lower-bound: Upper-bound: (c) Find a 90% confidence interval for μ Lower-bound: Upper-bound:

  • Please help! A simple random sample of size n=20 is drawn from a population that is...

    Please help! A simple random sample of size n=20 is drawn from a population that is normally distributed. The sample mean is found to be x = 59 and the sample standard deviation is found to be S = 11. Construct a 95% confidence interval about the population mean. The lower bound is . The upper bound is . (Round to two decimal places as needed.)

  • A random sample of n-15 heat pumps of a certain type yielded the following observations on lifetime (in years): 2.0 1.5 6.0 1.9 5.4 0.4 1.0 5.3 15.6 0.9 4.8 0.9 12.3 5.3 0.6 (a) Assume that the lifet...

    A random sample of n-15 heat pumps of a certain type yielded the following observations on lifetime (in years): 2.0 1.5 6.0 1.9 5.4 0.4 1.0 5.3 15.6 0.9 4.8 0.9 12.3 5.3 0.6 (a) Assume that the lifetime distribution is exponential and use an argument parallel to that of this example to obtain a 95% CI for expected (true average) lifetime. (Round your answers to two decimal places.) ) years (b) How should the interval of part (a) be...

  • Itl 5 LTE Confidence Interval for the P... DOCX -16 KB Close Confidence Interval for the Populati...

    statistics itl 5 LTE Confidence Interval for the P... DOCX -16 KB Close Confidence Interval for the Population Mean l. Determine the critical values for 80%, 90%, 95%, and 99%; 2. Construct 80%, 90%, 95%, and 99% confidence interval for the population mean given that the standard deviation of the population is 900 and the sample mean is 425 and the sample consist of 100 points of data 3. Find the T interval for the following: Construct 80% 90%. 95%,...

  • A random sample of 43 observations is used to estimate the population variance. The sample mean...

    A random sample of 43 observations is used to estimate the population variance. The sample mean and sample standard deviation are calculated as 68.5 and 3.1, respectively. Assume that the population is normally distributed. (You may find it useful to reference the appropriate table: chi-square table or F table) a. Construct the 95% interval estimate for the population variance. (Round intermediate calculations to at least 4 decimal places and final answers to 2 decimal places.) Confidence interval to b. Construct...

  • The annual earnings of 12 randomly selected computer software engineers have a sample standard deviation of $ 3626 Assum...

    The annual earnings of 12 randomly selected computer software engineers have a sample standard deviation of $ 3626 Assume the sample is from a normally distributed population. Construct a confidence interval for the population variance sigma squared σ2 and the population standard deviation sigma σ. Use a 95% level of confidence. Interpret the results. What is the confidence interval for the population variance sigma squared σ2​? What is the confidence interval for the population standard deviation sigma σ​? Please show...

  • The upper bound is ___ A simple random sample of size n = 40 is drawn...

    The upper bound is ___ A simple random sample of size n = 40 is drawn from a population. The sample mean is found to be x = 120.2 and the sample standard deviation is found to be s = 12.7. Construct a 99% confidence interval for the population mean. The lower bound is . (Round to two decimal places as needed.)

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT