Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Textbook Question
Chapter 12.2, Problem 5E
Suppose that we wish to study the effect of the stimulant digitalis on the blood pressure Y of rats over a dosage
12.4 Refer to Exercise 12.3. How many observations are needed for a 95% confidence interval to be 2 units in length if n1 = n2?
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Но: и
На: и
? :
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Chapter 12 Solutions
Mathematical Statistics with Applications
Ch. 12.2 - Suppose that you wish to compare the means for two...Ch. 12.2 - Refer to Exercise 12.1. Suppose that you allocate...Ch. 12.2 - Suppose, as in Exercise 12.1, that two populations...Ch. 12.2 - Refer to Exercise 12.3. How many observations are...Ch. 12.2 - Suppose that we wish to study the effect of the...Ch. 12.2 - Refer to Exercise 12.5. Consider two methods for...Ch. 12.2 - Refer to Exercise 12.5. Why might it be advisable...Ch. 12.2 - The standard error of the estimator 1 in a simple...Ch. 12.3 - Consider the data analyzed in Examples 12.2 and...Ch. 12.3 - Two computers often are compared by running a...
Ch. 12.3 - When Y1i, for i = 1, 2,, n, and Y2i, for i = 1,...Ch. 12.3 - Prob. 12ECh. 12.3 - Prob. 13ECh. 12.3 - Prob. 14ECh. 12.3 - A plant manager, in deciding whether to purchase a...Ch. 12.3 - Muck is the rich, highly organic type of soil that...Ch. 12.3 - Prob. 17ECh. 12.4 - Prob. 18ECh. 12.4 - Prob. 19ECh. 12.4 - Prob. 20ECh. 12.4 - Prob. 21ECh. 12.4 - Prob. 22ECh. 12.4 - Prob. 23ECh. 12.4 - Prob. 24ECh. 12.4 - Prob. 25ECh. 12.4 - Prob. 26ECh. 12.4 - Complete the assignment of treatments for the...Ch. 12 - Prob. 28SECh. 12 - Prob. 29SECh. 12 - Prob. 30SECh. 12 - Prob. 31SECh. 12 - Prob. 32SECh. 12 - Prob. 33SECh. 12 - Prob. 34SECh. 12 - The earths temperature affects seed germination,...Ch. 12 - An experiment was conducted to compare mean...Ch. 12 - Prob. 37SE
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- A research study comparing three treatment conditions produces T=20 with n=4 for the first treatment, T=10 with n=5 for the second treatment, and T=30 with n=5 for the third treatment. Calculate SSbetween treatments for this data.arrow_forwardA pilot study was performed to investigate the effect of temperature, x (in degree Fahrenheit) on the electrical power consumed, y (in Watt) by an automotive factory. Other factors were kept constant and the data were collected from the study. The summary of the data are given as follows: n = 8, 2x = 401, 2301, x? = 22495 2y? = 666509, Σ > xy = 118652. %3D Compute the equation of the least squares regression line of y on x. Interpret the equation obtained in part (i). Predict the power consumption for a temperature of 65°F. (i) (ii) (iii) (iv) Compute the coefficient of determination and explain.arrow_forwardFifty male subjects drank a measured amount x (in ounces) of a medication and the concentration y (in percent) in their blood of the active ingredient was measured 30 minutes later. The sample data are summarized by the following information: n = 50 Ex = 112.5 Ex? = 356.25 %3D Ey = 4.83 Ey = 0.667 Exy = 15.255 0 < x < 4.5 Or= 0.875 Or= 0.709 Or= -0.846 Or=0.460 Or= 0.965arrow_forward
- A psychologist noted that people have more difficulty sleeping in a bright room than in a dark room. She measured whether the intensity of the light could predict the time it took a sample of four participants to fall asleep. The data for this hypothetical study are listed in the following table. Intensity of Light (X) Time it Took to sleep (Y)5 10 10 18 20 30 40 25 M = 18.75 S = 15.48 M = 20.75 S = 8.69 r = .68 a. Create a scatter plot of the data b. Calculate r and r2 c. Report results in APA style. d. What do results meanarrow_forwardAn experiment was conducted to test the effect of a new cholesterol medicine. Fifteen people were treated with medicine X and 15 with medicine Y for a month, then the subjects' cholesterol level was measured. A significance test was conducted at the a = 0.01 level for the difference in the means of the cholesterol levels between medicine X and medicine Y. The test resulted in t = 2.73 and p = 0.003. If the alternative hypothesis in question was Ha: px - μy ‡ 0, where µx equals the mean cholesterol level for subjects taking medicine X and μy equals the mean cholesterol level for subjects taking medicine Y, what conclusion can be drawn? O There is not a significant difference in mean cholesterol level when using medicine X and medicine Y. O There is sufficient evidence that there is a difference in mean cholesterol level when using medicine X and medicine Y. O There is sufficient evidence that medicine X lowers cholesterol levels more than medicine Y. O The proportion of subjects who…arrow_forwardA psychologist noted that people have more difficulty sleeping in a bright room than in a dark room. She measured whether the intensity of the light could predict the time it took a sample of four participants to fall asleep. The data for this hypothetical study are listed in the following table. Intensity of Light (X) Time it Took to sleep (Y) 5 10 10 18 20 30 40 25 M = 18.75 S = 15.48 M = 20.75 S = 8.69 r = .68 a. Create a scatter plot of the data & Calculate r and r2b. Report results in APA style & What do results mean?arrow_forward
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