(c) Independent random samples of sizes n, = 16 and n2 = 25 from two normal populationsyield s = 4.8 and s2 3.5.(i)Construct a 95% C.I for the ratio of variances of the two populations(ii)Use (i) to construct a 95% C.I for the ratio of standard deviations02

c) Given information: n1=16n2=25s1=4.8s2=3.5 i) 95% C.I for the ratio of variances of the two…

Answered: (c) Independent random samples of sizes…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

An employer measured the number of units sold by his 400 sales employees. He noted that 40 woman employees had a mean sales of 122 and a variance of 60 while 35 men employees had a mean performance of 126 and a variance of 74. Assuming that the employees were randomly selected and the distribution is normal, is there a reason to believe that there is significant difference between the sales mean performances of the men and women sales employees? Use 0.01 level to test its significance. (Use the two sample mean z-test.)
It is known that the average yield per plant is 180 g and the variance is 250 g for a type of strawberry. 10 of this plant seed was grown in soils cultivated with a special method and average yield was observed to be 200 gr. Soil cultivation Test whether the method raises the yield average. (a = 0.05)
X is a random variable with mean X = 3, variance o = 2.
There are two samples. Sample 1 has n=10 and a sample variance of 4. Sample 2 has n=8 and a sample variance of 9. Calculate the standard error of the difference between the two sample means (to 2 decimal points). Assume that the variances in the two populations that produced the samples are equal.
The data from an independent-measures research study produce a sample mean difference of 4 points, and each sample has a variance of 10. If there are n = 20 scores in each sample, then what is the estimated standard error of the difference between means?
Records from previous years for a casualty insurance company show that its clients average a combined total of 1.9 auto accidents per day, with a variance of 0.31. The actuaries of the company claim that the current variance, oʻ, of the number of accidents per day is not equal to 0.31. A random sample of 17 recent days had a mean of 2 accidents per day with a variance of 0.62. If we assume that the number of accidents per day is approximately normally distributed, is there sufficient evidence to conclude, at the 0.05 level of significance, that the actuaries are correct? Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified below. (If necessary, consult a list of formulas.) (a) State the null hypothesis H, and the alternative hypothesis H,. p H, :0 H, :0 (b) Determine the type of test statistic to use. (Choose one) ▼ D=0 OSO O20 (c) Find the value of the test statistic. (Round…
Assume that the examination marks of students follow normal distri- butivn with unknown mean (4) but known variance (a?) = 0.25. Test the hypothesis Ho : u =8 against H: #8 with the level of significance a = 0.01, the sample mean being equal to 7.8 and the sample size being 50.
A researcher is interested whether a new drug is effective in changing patients' cholesterol levels. She divided 33 patients into 3 groups according to the dosage the patient received. The cholesterol levels of all patients are measured and used as the data for the Analysis of Variance (ANOVA). If she reported the test statistic F = 2.1 What is the degree of freedom for the numerator of the F statistic? What is the degree of freedom for the denominator of the F statistic? What is the P-value of the F-test? (Round to 3 decimals) Given the significance level of 0.01, what can she conclude from the test? *The patients in differnt groups have simliar average cholesterial levels. The drug made no difference. *At least one group of patients have an average cholesterol level that is different from the other groups. The drug may have an effect.
Ritalin has been shown to increase attention span and improve academic performance in children with ADHD (Evans et al., 2001). To demonstrate the effectiveness of the drug, a researcher selects a sample of n = 20 children diagnosed with ADHD and measures each child’s attention span before and after taking the drug. The data show an average increase of attention span of MD = 4.8 minutes with a variance of s2 = 125 for the sample of difference scores. Is this result sufficient to conclude that Ritalin significantly improves attention span? Use a one-tailed test at .05. Compute the 80% confidence interval for the mean chance in attention span for the population.
The average size of a farm in Pekan I is 185 acres. The average size of a farm in Pekan II is 100 acre. Assume that the data were obtained from two samples with standard deviations of 38 acres and 12 acres, and sample size of 8 and 9 respectively. Can it be concluded at α = 0.05 that the average size of the farms in Pekan I and Pekan II are different? (Assume equal variances)
2. The average zone of inhibition (in mm) for mouthwash L as tested by the medical technology students has been known to be 9mm. A random sample of 10 mouthwash L was tested and the test yielded an average zone of inhibition of 7.5mm with a variance of 25 mm. Is there enough reason to believe that the anti-bacterial property of the mouthwash has decreased? Test the hypothesis that the average zone of inhibition of the mouthwash is no less than 9mm using 0.05 level of significance. A. State the hypotheses. B. Determine the test statistic to use. C. Determine the level of significance, critical value, and the decision rule. D. Compute the value of the test statistic. E. Make a decision. F. Draw a conclusion.
In the experiment of A and B consumers, 12 sample points are set for A consumers, and the average value of word-of-mouth is 3 with a variance of 1.2; 8 sample points are set for B consumers, and the average value of word-of-mouth is 5 with a variance of 1.6. Compare whether there is significant difference between the average word-of-mouth of A and B consumers. (a=0.05)

Recommended textbooks for you

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

Elementary Statistics: Picturing the World (7th E…

Statistics

ISBN:

9780134683416

Author:

Ron Larson, Betsy Farber

Publisher:

PEARSON

The Basic Practice of Statistics

Statistics

ISBN:

9781319042578

Author:

David S. Moore, William I. Notz, Michael A. Fligner

Publisher:

W. H. Freeman

Introduction to the Practice of Statistics

Statistics

ISBN:

9781319013387

Author:

David S. Moore, George P. McCabe, Bruce A. Craig

Publisher:

W. H. Freeman

SEE MORE TEXTBOOKS

(c) Independent random samples of sizes n, = 16 and n2 yield s,= 4.8 and s2 3.5. = 25 from two normal populations (i) Construct a 95% C.I for the ratio of variances of the two populations