The scores on a placement test given to college freshmen for the past five years are approximately normally distributed with a mean μ = 74 and a variance σ^2 = 8. Would you still consider σ^2 = 8 to be a validvalue of the variance if a random sample of 20 students who take the placement test this year obtain a value ofs^2 = 20?

The scores on a placement test given to college freshmen for the past five years are approximately normally distributed with a mean μ = 74 and a variance σ^2 = 8. Would you still consider σ^2 = 8 to be a validvalue of the variance if a random sample of 20 students who take the placement test this year obtain a value ofs^2 = 20?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

See similar textbooks

Similar questions

The standard error of the mean will change among mutliple samples even if the standard deviation and sample sizes are held constant True False
A medical team was asked to study the difference in systolic blood pressure (BP) between men (µ1) and women (µ2) with heart trouble. The BP measurements are normally distributed. The variance of the men’s group is equal to that of the women’s group. For a random sample of 4 men, thesample average is 175 and the sample standard deviation is 16. For a random sample of 5 women, the sample average is 145 and the sample standard deviation is 12. What is the 95% confidence interval estimate for the difference between the two means? 8.02 to 51.98 5.05 to 34.05 −4.20 to 33.20 −0.65 to 29.65
(a) State the null hypothesis H, and the alternative hypothesis H . H :U H :0 1 (b) Determine the type of test statistic to use. (Choose one) ▼ (c) Find the value of the test statistic. (Round to three or more decimal places.) (d) Find the p-value. (Round to three or more decimal places.) (e) Can we support the claim that the variance of cholesterol levels of adult males is greater than 514? O Yes ONo
The mean ±1 sd of ln [calcium intake (mg)] among 25 females, 12 to 14 years of age, below the poverty level is 6.56 ± 0.64. Similarly, the mean ± 1 sd of ln [calcium intake (mg)] among 40 females, 12 to 14 years of age, above the poverty level is 6.80 ± 0.76. 8.2 Test for a significant difference between the variances of the two groups. Find the P value. Do not use excell. Solve the step by step
PLEASE ANSWER IT WITHIN 30 MINS WITH COMPLETE SOLUTION
Describe the important characteristics of the variance of a conditional distribution of an error term in a linear regression. What are the implicationsfor OLS estimation?
Hello, When I sum up the variance, I'm getting 2.75. And not 1.65. Also, how did you get the xi-mean in each column? Thanks
A study of blood samples of 64 men shows a mean count of 5million RBC per cubic ml., with a variance of 0.06. A tabulation of64 women from the same population group show a mean countof 4.5 million, with a variance of 0.13. What is the probability offinding a woman with a count of less than 5 million?
A study of B.A. (Hons.) Economics examination results of 1000 students in 1990 gave the mean теаn grade as 78 and the standard deviation as 8.0. A similar study in 1995 revealed the mean grade of the group as 80 and the standard deviation as 7-6. In which year was there the greater (i) absolute dispersion, (ii) relative dispersion ? What can we say about the average performance of the students over time?
A study was conducted to compare the length of time between men and women to assemble a certain product. Sample standard deviation in a random sample of times for 11 men was 8.6 minutes, and sample standard deviation in a random sample of times for 13 women was 6.9 minutes. Past experience indicate that population of times is normal for both men and women. Is it sufficient sample evidence to conclude that the variance of the lengths of time for men is larger than the variance of the lengths of time for women? Test appropriate hypothesis at a = 0.05 level of significance using critical value approach. Use S²/S2 as test statistic. Construct a 90% confidence interval for the ratio of two population variances. a. State null and research hypotheses H: H₁ b. The observed value of test statistic is c. State the rejection region d. Insert the word sufficient or insufficient into the following statement. There is of time for men is larger than the variance of the lengths of time for women.…
The blood pressure and weight of Jellystone Park bears are correlated and .5 is the correlation coefficient of blood pressure with weight. The average blood pressure is 150 with variance 36, for Jellystone Park bears. For a randomly selected bear with average weight if we predict its blood pressure is 150 after weighing it, using SLR, what is our expected squared error?