Probability and Statistics for Engineering and the Sciences
9th Edition
ISBN: 9781305251809
Author: Jay L. Devore
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 14.2, Problem 20E
To determine
Explain whether to use one sample t confidence interval for the true bending rigidity.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A study of the properties of metal plate-connected trusses used for roof support yielded the following observations on axial stiffness index (kips/in.) for plate lengths 4, 6, 8, 10, and 12 in:
4:
323.2
409.5
311.0
326.5
316.8
349.8
309.7
6:
423.1
347.2
361.0
404.5
331.0
348.9
381.7
8:
393.4
366.2
351.0
357.1
409.9
367.3
382.0
10:
362.7
452.9
461.4
433.1
410.6
384.2
362.6
12:
418.4
441.8
419.9
410.7
473.4
441.2
465.8
Does variation in plate length have any effect on true average axial stiffness? State the relevant hypotheses using analysis of variance.
H0: ?1 ≠ ?2 ≠ ?3 ≠ ?4 ≠ ?5Ha: at least two ?i's are equalH0: ?1 = ?2 = ?3 = ?4 = ?5Ha: all five ?i's are unequal H0: ?1 = ?2 = ?3 = ?4 = ?5Ha: at least two ?i's are unequalH0: ?1 ≠ ?2 ≠ ?3 ≠ ?4 ≠ ?5Ha: all five ?i's are equal
Test the relevant hypotheses using analysis of variance with ? = 0.01. Display your results in an ANOVA table. (Round your answers to two decimal places.)
Source
Degrees offreedom
Sum…
Consider the accompanying data on flexural strength (MPa) for concrete beams of a certain type.
5.5
7.2
7.3
6.3
8.1
6.8
7.0
7.2
6.8
6.5
7.0
6.3
7.9
9.0
8.7
8.7
7.8
9.7
7.4
7.7
9.7
8.0
7.7
11.6
11.3
11.8
10.7
The data below give accompanying strength observations for cylinders.
6.6
5.8
7.8
7.1
7.2
9.2
6.6
8.3
7.0
8.4
7.3
8.1
7.4
8.5
8.9
9.8
9.7
14.1
12.6
11.3
Prior to obtaining data, denote the beam strengths by X1, . . . , Xm and the cylinder strengths by Y1, . . . , Yn. Suppose that the Xi's constitute a random sample from a distribution with mean μ1 and standard deviation σ1 and that the Yi's form a random sample (independent of the Xi's) from another distribution with mean μ2 and standard deviation σ2.
Compute the estimated standard error. (Round your answer to three decimal places.)
(c) Calculate a point estimate of the ratio σ1/σ2 of the two standard deviations. (Round your answer to three decimal places.)
(d) Suppose a single beam and a single cylinder are…
Consider the accompanying data on flexural strength (MPa) for concrete beams of a certain type.
5.3
7.2
7.3
6.3
8.1
6.8
7.0
7.1
6.8
6.5
7.0
6.3
7.9
9.0
9.0
8.7
7.8
9.7
7.4
7.7
9.7
7.9
7.7
11.6
11.3
11.8
10.7
The data below give accompanying strength observations for cylinders.
6.8
5.8
7.8
7.1
7.2
9.2
6.6
8.3
7.0
9.0
7.6
8.1
7.4
8.5
8.9
9.8
9.7
14.1
12.6
11.8
Prior to obtaining data, denote the beam strengths by X1, . . . , Xm and the cylinder strengths by Y1, . . . , Yn. Suppose that the Xi's constitute a random sample from a distribution with mean ?1 and standard deviation ?1 and that the Yi's form a random sample (independent of the Xi's) from another distribution with mean ?2 and standard deviation ?2.
(a) Calculate the estimate for the given data. (Round your answer to three decimal places.) (b) Use rules of variance to obtain an expression for the variance and standard deviation (standard error) of the estimator in part (a).
V(X − Y)
=
V(X) + V(Y)
=…
Chapter 14 Solutions
Probability and Statistics for Engineering and the Sciences
Ch. 14.1 - What conclusion would be appropriate for an...Ch. 14.1 - The article Racial Stereotypes in Childrens...Ch. 14.1 - It is hypothesized that when homing pigeons are...Ch. 14.1 - The article Application of Methods for Central...Ch. 14.1 - An information-retrieval system has ten storage...Ch. 14.1 - The article The Gap Between Wine Expert Ratings...Ch. 14.1 - Criminologists have long debated whether there is...Ch. 14.1 - The article Psychiatric and Alcoholic Admissions...Ch. 14.1 - Prob. 9ECh. 14.1 - Prob. 10E
Ch. 14.1 - Prob. 11ECh. 14.2 - Consider a large population of families in which...Ch. 14.2 - A study of sterility in the fruit fly (Hybrid...Ch. 14.2 - Prob. 14ECh. 14.2 - A certain type of flashlight is sold with the four...Ch. 14.2 - Let X = the number of adult police contacts for a...Ch. 14.2 - In a genetics experiment, investigators looked at...Ch. 14.2 - The article A Probabilistic Analysis of Dissolved...Ch. 14.2 - Each headlight on an automobile undergoing an...Ch. 14.2 - Prob. 20ECh. 14.2 - Prob. 21ECh. 14.2 - The article A Method for the Estimation of Alcohol...Ch. 14.2 - The article Nonbloated Burned Clay Aggregate...Ch. 14.3 - The accompanying two-way table was constructed...Ch. 14.3 - In an investigation of alcohol use among college...Ch. 14.3 - Contamination of various food products is an...Ch. 14.3 - The article Human Lateralization from Head to...Ch. 14.3 - Prob. 28ECh. 14.3 - The accompanying data on degree of spirituality...Ch. 14.3 - Three different design configurations are being...Ch. 14.3 - A random sample of smokers was obtained, and each...Ch. 14.3 - Eclosion refers to the emergence of an adult...Ch. 14.3 - Prob. 33ECh. 14.3 - Prob. 34ECh. 14.3 - Prob. 35ECh. 14.3 - Consider the accompanying 2 3 table displaying...Ch. 14 - The article Birth Order and Political Success...Ch. 14 - Does the phase of the moon have any bearing on...Ch. 14 - Prob. 39SECh. 14 - The authors of the article Predicting Professional...Ch. 14 - The accompanying two-way frequency table appears...Ch. 14 - Prob. 42SECh. 14 - Prob. 43SECh. 14 - Prob. 44SECh. 14 - Prob. 45SECh. 14 - The NCAA basketball tournament begins with 64...Ch. 14 - Have you ever wondered whether soccer players...Ch. 14 - Do the successive digits in the decimal expansion...Ch. 14 - Prob. 49SE
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- The article “Withdrawal Strength of Threaded Nails” (D. Rammer, S. Winistorfer, and D. Bender, Journal of Structural Engineering 2001:442–449) describes an experiment comparing the ultimate withdrawal strengths (in N/mm) for several types of nails. For an annularly threaded nail with shank diameter 3.76 mm driven into spruce-pine-fir lumber, the ultimate withdrawal strength was modeled as lognormal with μ = 3.82 and σ = 0.219. For a helically threaded nail under the same conditions, the strength was modeled as lognormal with μ = 3.47 and σ = 0.272. a) What is the mean withdrawal strength for annularly threaded nails? b) What is the mean withdrawal strength for helically threaded nails? c) For which type of nail is it more probable that the withdrawal strength will be greater than 50 N/mm? d) What is the probability that a helically threaded nail will have a greater withdrawal strength than the median for annularly threaded nails? e) An experiment is performed in which withdrawal…arrow_forwardThe article in the ASCE Journal of Energy Engineering (1999, Vol. 125, pp.59-75) describes a study of the thermal inertia properties of autoclaved aerated concrete used as a building material. Five samples of the material were tested in a structure, and the average interior temperatures (°C) reported were as follows: 23.01, 22.22, 22.04, 22.62, and 22.59. Test that the average interior temperature is equal to 22.5°C using alpha (a) = 0.05. This problem is a test on what population parameter? What is the null and alternative hypothesis? What are the Significance level and type of test? What standardized test statistic will be used? What is the standard test statistic? What is the Statistical Decision? What is the statistical decision in the statement form?arrow_forwardThe data given is shown below 40 40 43 46 44 49 51 54 46 51 47 49 49 45 45 44 45 41 49 52 51 54 50 51 41 52 53 50 46 56 42 42 40 42 49 47 51 48 46 57 48 55 49 46 57 44 49 43 44 43 51 48 48 46 49 Class width = 6 Find the following: A. Decile (5th) B. Quartile (2nd) C. Skewness D. Kurtosisarrow_forward
- Consider the following 10 measurements about the cohesion of a soil: 12 kPa, 14 kPa, 15 kPa, 14.5 kPa, 16.0 kPa, 18 kPa, 15 kPa, 16.2 kPa, 17. 6 kPa, 13 kPa. Work out the solutions of the following two problems, assuming the cohesion follows the normal and lognormal distributions, respectively. (1) Draw the PDF of the cohesion; (2) Evaluate the probability that the cohesion based on the PDF is less than 5 kPa, 10 kPa, and 15 kPa; (3) Assess the effect of the type of distribution on the results.arrow_forwardIn 58 specimens of a new aluminum alloy that is developed as a material for the next generation of aircraft, the compressive strength was measured, obtaining the following results: 66.4 67.7 68.0 68.0 69.5 70.4 71.6 72.9 69.0 69.169.2 69.3 69.3 69.5 70.3 71.5 72.7 68.9 69.9 70.070.0 70.1 70.2 70.3 71.3 72.6 68.8 69.8 70.8 70.971.0 71.1 71.2 71.3 72.4 68.6 69.8 70.6 71.8 71.871.9 72.1 72.2 72.3 68.4 69.7 70.6 71.7 73.3 73.574.2 74.5 75.3 68.3 69.6 70.5 71.6 73.1 a. Find a 95% confidence interval for the mean strength of the aluminum alloy.b. If you want to test Ho: Mu = 72 against H1: Mu different from 72 with a significance level of 0.05, what is the probability of a type II error for Mu = 71?arrow_forwardIn 58 specimens of a new aluminum alloy that is developed as a material for the next generation of aircraft, the compressive strength was measured, obtaining the following results: 66.4 67.7 68.0 68.0 69.5 70.4 71.6 72.9 69.0 69.169.2 69.3 69.3 69.5 70.3 71.5 72.7 68.9 69.9 70.070.0 70.1 70.2 70.3 71.3 72.6 68.8 69.8 70.8 70.971.0 71.1 71.2 71.3 72.4 68.6 69.8 70.6 71.8 71.871.9 72.1 72.2 72.3 68.4 69.7 70.6 71.7 73.3 73.574.2 74.5 75.3 68.3 69.6 70.5 71.6 73.1 a. Find a 95% confidence interval for the mean resistance of thealuminium alloy.b. If you want to test Ho:Mu =72 against H1: Mu different from 72 with a significance level of 0.05, what is the probability of a type II error for Mu= 71?arrow_forward
- Answer the following: 1. Test Stat 2. Critical Region: Select one: a. T1.761 c. T>2.14 d. T>abs(2.145) 3. Conclusion: At 5% level of significance… Select one: a. the new type of fabric does not exceed the WRA of the top current brand b. the new type of fabric exceeds the WRA of the top current brandarrow_forwardBased on teh attached data, does it appear that magnets reduce backpain?arrow_forwardQ1 A) List down the measures of central tendency and measures of dispersion 2) The operations manager of a plant that manufactures tires wants to compare the actual inner diameters of two grades of tires, each of B) which is expected to be 575 millimeters. A sample of five tires of each grade was selected, and the results representing the inner diameters of the tires, ranked from smallest to largest, are as follows. Grade X grade Y 568 570 575 578 584 573 574 575 577 578 requirement. a) for each of the tow grades of tries, compute the mwan, median, and standred deviation. b) which grade of tire providing better quality? explain. c) what would be the effect on your answer in (a) and (b) if the last value for grade Y were 588 insert 578 explain. C) The file contins the overall miles per gallon (MPG) OF 2010 family sedan: 24 21 22 23 24 34 34 34 20 20 22 22 44 32 20 20 22 20 39 20 Source:…arrow_forward
- The Turbine Oil Oxidation Test (TOST) and the Rotating Bomb Oxidation Test (RBOT) are two different procedures for evaluating the oxidation stability of steam turbine oils. An article reported the accompanying observations on x = TOST time (hr) and y = RBOT time (min) for 12 oil specimens. TOST 4200 3600 3750 3650 4050 2770 RBOT 370 345 375 315 350 205 TOST 4870 4525 3450 2700 3750 3325 RBOT 400 380 285 220 345 290 (a) Calculate the value of the sample correlation coefficient. (Round your answer to four decimal places.) r = Carry out a test of hypotheses to decide whether RBOT Time and TOST time are linearly related. (Use ? = 0.05.) Calculate the test statistic and determine the P-value. (Round your test statistic to two decimal places and your P-value to three decimal places.) t = P-value =arrow_forwardThe spike stature of the plants grown from the seeds of the porcine separates (Dactylis glomerata L) collected from the University campus and İbradı Eynif pasture are given below. In this plant, compare whether there is a difference between regions in terms of spike height. Virgo Height (cm) Data obtained from plants collected from university campus 5 6 8 7 8 6 5 5 4 6 6 Data obtained from plants collected from Eynif pasture 12 9 11 9 9 11 9 10 11 10 Note: Your results interpretation according to two different possibilities (Do it separately, assuming that it is 0.07 and 0.04).arrow_forwardAutomated electron backscattered diffraction is nowbeing used in the study of fracture phenomena. The followinginformation on misorientation angle (degrees)was extracted from the article “Observations on theFaceted Initiation Site in the Dwell-Fatigue TestedTi-6242 Alloy: Crystallographic Orientation and SizeEffects” (Metallurgical and Materials Trans., 2006:1507–1518).Class: 02,5 52,10 102,15 152,20Rel freq: .177 .166 .175 .136Class: 202,30 302,40 402,60 602,90Rel freq: .194 .078 .044 .030a. Is it true that more than 50% of the sampled anglesare smaller than 15°, as asserted in the paper?b. What proportion of the sampled angles are at least30°?c. Roughly what proportion of angles are between10° and 25°?d. Construct a histogram and comment on any interestingfeatures.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman
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
Statistics 4.1 Point Estimators; Author: Dr. Jack L. Jackson II;https://www.youtube.com/watch?v=2MrI0J8XCEE;License: Standard YouTube License, CC-BY
Statistics 101: Point Estimators; Author: Brandon Foltz;https://www.youtube.com/watch?v=4v41z3HwLaM;License: Standard YouTube License, CC-BY
Central limit theorem; Author: 365 Data Science;https://www.youtube.com/watch?v=b5xQmk9veZ4;License: Standard YouTube License, CC-BY
Point Estimate Definition & Example; Author: Prof. Essa;https://www.youtube.com/watch?v=OTVwtvQmSn0;License: Standard Youtube License
Point Estimation; Author: Vamsidhar Ambatipudi;https://www.youtube.com/watch?v=flqhlM2bZWc;License: Standard Youtube License