Suppose you administer a certain aptitude test to a random sample of 95 students in your school, and that the mean score is 105. We want to determine the mean µ of the population of all students in the school. Assume a standard deviation of σ = 15 for the test. We want to construct a 99% confidence interval: a) The point estimate is ______. b) The standard error = ___________ margin of error = c) We are 99% confident that the true ________________ falls between ________ and ________. d) If we decrease the sample size to n=45, The standard error will ______________ the margin of error will _______and therefore the width of the confidence interval will get __________.

Suppose you administer a certain aptitude test to a random sample of 95 students in your school, and that the mean score is 105. We want to determine the mean µ of the population of all students in the school. Assume a standard deviation of σ = 15 for the test. We want to construct a 99% confidence interval: a) The point estimate is . b) The standard error = _ margin of error = c) We are 99% confident that the true __ falls between and . d) If we decrease the sample size to n=45, The standard error will the margin of error will _and therefore the width of the confidence interval will get ________.

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

Age Age Gender Under 40 40 or Older Total Male 12 2 14 Female 8 3 11 Total 20 5 25 The table above shows the distribution of age and gender for 25 people who entered a contest. If the contest winner will be selected at random, what is the probability that the winner will be either a female or 40 or older? 13/25 16/25 3/25 10/25
If an observation has a z-score of -1.5, how many standard deviations is it above or below the mean? O 0.066 standard deviations above the mean O 1.5 standard deviations above the mean O 1.5 standard deviations below the mean O 0.066 standard deviations below the mean
Which of the following statements are TRUE: (a) If the standard deviation of a collection of data is zero then all the data in this collection are equal to each other (b) If you work for Quality Control in a company then your preference is that the measurements of your company's product have a large standard deviation (c) If the class 20 to 29 of a class frequency distribution contains the most data then this class 20 to 29 is the mode (d) If a value is unlikely then this value must be significant (e) The 5-Number summary of a collection of data are the minimum, mean, standard deviation, median, and maximum of this collected data (f) if the Zscore of a value is -2.44 then this value is a significant value (g) The best indicator of a typical house price in Lake Worth is the mean of the Lake Worth House prices
Which of the following describes a Type I error? A. Error associated with decisions to retain the null B. You decide that there is a statistical difference when there is actually no difference C. You decide that there is no difference when there is actually a statistical difference
Two normal distributions are compared. One has a mean of 10 and a standard deviation of 10. The second normal distribution has a mean of 10 and a standard deviation of 2. Which of the following is true? The dispersions of the distributions are different. The dispersions of the distributions are the same. The distributions are from two different families of distributions. The locations of the distributions are different.
(Q5). The data on monthly rents, in dollars, for independent random samples of newly completed apartments in three U.S. regions are presented in the table below. Assume that the population standard deviation of the monthly rents in the three regions are equal and the populations are normally distributed. Northeast South _____West 1005 891 1025 898 630 1012 948 861 1090 1181 926 _______________________________ (a). Do the data indicate that there is a difference in the monthly rent for the three regions? Discuss the assumptions you have made to carry out your analysis. Use a significance level of 10%. (b). Interpret your conclusion in…
Use z scores to compare the given values. The tallest living man at one time had a height of 238 cm. The shortest living man at that time had a height of 142.4 cm. Heights of men at that time had a mean of 175.45 cm and a standard deviation of 5.59 cm. Which of these two men had the height that was more extreme? ... Since the z score for the tallest man is z = 0 and the z score for the shortest man is z = the man had the height that was Im- more extreme. (Round to two decimal places.) shortest tallest
There are several sections of Statistics; some in the morning and some in the afternoon. We randomly select n1 40 from the morning section and 44 from the afternoon section. The averages n2 of their scores are X1 76.3 for the morning section and X, = 71.9 for the afternoon section. The known standard deviations of their scores are 01 12.05 for the morning section and 02 13.06 for the afternoon section. Test the claim that the average for all students in the morning and afternoon section is the same. Use a a = 0.05 significance level. a. What is the negative critical region? Give your answer to two decimal places. z c. What is the test statistic? Give your answer to two decimal places. z = d. Do we reject or fail to reject the null hypothesis? OReject Ho OFail to reject Họ
Out of 200 people sampled, 78 had dogs. Based on this, construct a 95% confidence interval for the true population proportion of people with dogs. give your answers as decimals to three places ________ < p < _______
A random sample of 15 exam scores showed a standard deviation of 6.0 points. Find the 95 percent confidence interval for the population standard deviation. Use Appendix E to obtain the values of χ2LχL2 and χ2UχU2 . (Round your answers to 2 decimal places.) The 95% confidence interval is from ______ to __________ .
.
Suppose the scores on an exam have a mean of 70 with a standard deviation of 10. If one student hasa test result with a z-score of -0.8 and a second student has a test result with a Z-score of 1.8, how many points higher was the second student's score than that of the first? O a. 10 O b. 20 O c. 2.6 O d. 13 O e. 26