WebAssign for Devore's Probability and Statistics for Engineering and the Sciences, 9th Edition [Instant Access], Single-Term
9th Edition
ISBN: 9780357893104
Author: Devore; Jay L.
Publisher: Cengage Learning US
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 10.2, Problem 16E
Reconsider the axial stiffness data given in Exercise 8. ANOVA output from Minitab follows:
Analysis of Variance for Stiffness | |||||
Source | DF | SS | MS | F | P |
Length | 4 | 43993 | 10998 | 10.48 | 0.000 |
Error | 30 | 31475 | 1049 | ||
Total | 34 | 75468 | |||
Level | N | StDev | |||
4 | 7 | 333 .21 | 36.59 | ||
6 | 7 | 368.06 | 28.57 | ||
8 | 7 | 375.13 | 20.83 | ||
10 | 7 | 407 .36 | 44 .51 | ||
12 | 7 | 437.17 | 26.00 | ||
Pooled StDev = 32.3 9 |
Tukey’s pairwise comparisons
Family error rate = 0.0500
Individual error rate = 0.00693
Critical value = 4.10
Intervals for (column level mean) – (row level mean)
4 | 6 | 8 | 10 | |
6 | -85. 0 | |||
15.4 | ||||
8 | -92.1 | -57.3 | ||
8.3 | 43.1 | |||
10 | -124.3 | -89. 5 | -82.4 | |
-23. 9 | 10. 9 | 18 . 0 | ||
12 | -154.2 | -119.3 | -112.2 | -80.0 |
-53. 8 | -18. 9 | -11. 8 | 20.4 |
a. Is it plausible that the variances of the five axial stiffness index distributions are identical? Explain.
b. Use the output (without reference to our F table) to test the relevant hypotheses.
c. Use the Tukey intervals given in the output to determine which means differ, and construct the corresponding underscoring pattern.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
The valve pressure was tested on 250 engines and the mean pressure was 5.9 lbs/square inch. Assume the variance is known to be 0.36. If the valve was designed to produce a mean pressure of 5.8 lbs/square inch, is there sufficient evidence at the 0.02 level that the valve performs about the specifications?
A wine enthusiast named Suds collected data on the alc content (percent by volume) of wine for one grape variety in 2012 by a random sample of winemakers in Italy. Suds created the following Table:
Alcohol %
Mean
13.093
Std Error
0.1143
Median
13.165
Mode
13.17
Std Deviation
0.5111
Sample Variance
0.2612
Kurtosis
-0.8385
Skew
-0.1747
Range
1.68
Minimum
12.2
Maximum
13.88
Sum
261.86
Count
20
Use the table to determine whether mean alc content of all wines for that grape in 2012 in Italy was greater than 12.75% at the 0.1 significance.
a) State the null and alternaternative hypothesis.
b) What is the calculated value of the associated test statistic and what is the critical value of the associated test statistic?
c) State your decision about the null hypothesis by comparing calculated and critical values of the statistic. State your conclusion(describe what the decision means in this problem).
Given the following ANOVA table, calculate the F-ratio and the F critical values.
ANOVA for Regression
Source
DF
MS
F
Group
5.450
Error
19.006
10
Total
24.456
13
F- ratio = 2.41; F critical = 3.71
O F- ratio = 14.65; F critical = 4.76
O F- ratio - 0.96; F critical = 3.71
O F- ratio = 19.87; F critical - 4.76
Chapter 10 Solutions
WebAssign for Devore's Probability and Statistics for Engineering and the Sciences, 9th Edition [Instant Access], Single-Term
Ch. 10.1 - In an experiment to compare the tensile strengths...Ch. 10.1 - Suppose that the compression-strength observations...Ch. 10.1 - The lumen output was determined for each of I = 3...Ch. 10.1 - It is common practice in many countries to destroy...Ch. 10.1 - Consider the following summary data on the modulus...Ch. 10.1 - The article Origin of Precambrian Iron Formations...Ch. 10.1 - An experiment was carried out to compare...Ch. 10.1 - A study of the properties of metal plate-connected...Ch. 10.1 - Six samples of each of four types of cereal grain...Ch. 10.1 - In single-factor ANOVA with I treatments and J...
Ch. 10.2 - An experiment to compare the spreading rates of...Ch. 10.2 - In Exercise 11, suppose x3. = 427.5. Now which...Ch. 10.2 - Prob. 13ECh. 10.2 - Use Tukeys procedure on the data in Example 10.3...Ch. 10.2 - Exercise 10.7 described an experiment in which 26...Ch. 10.2 - Reconsider the axial stiffness data given in...Ch. 10.2 - Prob. 17ECh. 10.2 - Consider the accompanying data on plant growth...Ch. 10.2 - Prob. 19ECh. 10.2 - Refer to Exercise 19 and suppose x1 = 10, x2 = 15,...Ch. 10.2 - The article The Effect of Enzyme Inducing Agents...Ch. 10.3 - The following data refers to yield of tomatoes...Ch. 10.3 - Apply the modified Tukeys method to the data in...Ch. 10.3 - The accompanying summary data on skeletal-muscle...Ch. 10.3 - Lipids provide much of the dietary energy in the...Ch. 10.3 - Samples of six different brands of diet/imitation...Ch. 10.3 - Although tea is the worlds most widely consumed...Ch. 10.3 - For a single-factor ANOVA with sample sizes Ji(i =...Ch. 10.3 - When sample sizes are equal (Ji = J). the...Ch. 10.3 - Reconsider Example 10.8 involving an investigation...Ch. 10.3 - When sample sizes are not equal, the non...Ch. 10.3 - In an experiment to compare the quality of four...Ch. 10.3 - Prob. 33ECh. 10.3 - Simplify E(MSTr) for the random effects model when...Ch. 10 - An experiment was carried out to compare flow...Ch. 10 - Cortisol is a hormone that plays an important role...Ch. 10 - Numerous factors contribute to the smooth running...Ch. 10 - An article in the British scientific journal...Ch. 10 - Prob. 39SECh. 10 - Prob. 40SECh. 10 - Prob. 41SECh. 10 - The critical flicker frequency (cff) is the...Ch. 10 - Prob. 43SECh. 10 - Four types of mortarsordinary cement mortar (OCM)....Ch. 10 - Prob. 45SECh. 10 - Prob. 46SE
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
- Given the following ANOVA table, calculate the F-ratio and the F critical values. ANOVA for Regression Source SS DF MS F Group 9.875 Error 14.581 10 Total 24.456 13 F- ratio = 2.26; F critical = 3.71 F- ratio 0.46; F critical = 4.76 %D %3D F- ratio = 14.65; F critical = 3.71 F- ratio = 1.46; F critical = 4.76 %3Darrow_forwardAUA wants to determine whether the mean cumulative GPA, CGPA is significantly different among undergraduate and graduate students (Sheet 31). They collect data on several undergraduate and graduate students. What can they conclude at alpha=0.05? Select one: a. t(stat)=2.56, which is greater than t(cr)=1.68, therefore, we can conclude that there is significant difference in mean CGPAs b. Assuming unequal variances, t(stat)=2.56, which is greater than t(cr)=2.02, therefore, we can conclude that there is significant difference in mean CGPAs c. t(stat)=1.15, which is less than t(cr)=2.12, therefore, we can conclude that there is no significant difference in mean CGPAs d. Assuming equal variances, t(stat)=2.56, which is greater than t(cr)=2.02, therefore, we can conclude that there is significant difference in mean CGPAsarrow_forwardAn experiment to explore the pain threshold to electrical shocks for males and females resulted in the data summary given below. Do the data provide sufficient evidence to indicate s significant difference in the variability of pain threshold for men and women. Use a = .10. What can be said about p-value? Sample Size Mean Variance Males 14 16.2 2.7 Females 10 14.9 26.4arrow_forward
- A recent Nielsen analysis found that the typical U.S. smartphone user is spending an average of 220 minutes per day using apps. We speculate that the average time spent using apps for Generation X smartphone users (aged 41-56 years) is less than the national average. The hypotheses are Ho: H = 220 minutes versus Ha: µ < 220 minutes. Summary results from R are provided. Summary Statistics Std. Dev (s) Mean Sample Size (n) 205 minutes 63.25 minutes 31arrow_forwardAn engineer has designed a valve that will regulate water pressure on an automobile engne. The valve was tested on 130 engines and the mean pressure was 5.1 Ibs/square inch. Assume the variance is known to be 0.25 if the valve was designed to produce a mean pressure of 5 lbs/square inch, is there sufficient evidence at the 0.05 level that the valve performs above the specifications? State the null and alternative hypotheses for the above scenario Answer Ho H₂ Tables Keypad Keyboard Shortcutsarrow_forwardThe following is the ANOVA data obtained from a balanced CRD: ANOVA: Source of Variation Degree of Freedom Sum of Squares Mean Squares F-calculated TRT 10.5 90.4 ERROR TOTAL --- 20 42 --- --- Your are interested to evaluate treatments effects using the following hypothesis: Ho: M1 = μ2 = Ut ---against--- HA: µ1 ‡ µ2 ‡... Mt 1. What is the number of treatments in this experiment? (place your answer in the box below) 2. Evaluate the F calculated for the treatment effect, and indicate if you are going to reject(R) or fail to reject(FR) the null hypothesis using an ALPHA= 0.01 (R/FR; place your answer right beside the calculated number of treatments)arrow_forward
- By what numerical value should SS be divided in order to compute an unbiased variance?arrow_forwardA pharmaceutical manufacturer forms tablets by compressing a granular material that contains the active ingredient and various fillers. The force in kilograms (kg) applied to the tablet varies a bit and follows the Normal distribution with mean 5 kg and standard deviation 0.2 kg. The process specifications call for applying a force between 11.2 and 12.2 kg. What percent of tablets are subject to a force that meets the specifications? The manufacturer adjusts the process so that the mean force is at the center of the specifications, μ = 11.7 kg. The standard deviation remains 0.2 kg. What percent now meets the specificationsarrow_forwarda) Soil has been improved to increase the strength of a ground. The average compressive strength of 61 samples before treatment is 45 kg / cm2 and the standard deviation is 6.75 kg / cm2; The average compressive strength of 56 samples after the improvement is 52.5 kg / cm2 and the standard deviation is 8 kg / cm2. Determine whether the improvement application changes the standard deviation of the soil strength or not at the 5% significance level (15 P). b) Find the confidence intervals at the 7% significance level of the mean compressive strength of the sample after improvement?arrow_forward
- A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expense among three industries rejected the null hypothesis. The mean square error (MSE) was 195. The following table summarized the results: Education Tax Services Food Services Number Sampled 10 14 16 Mean Expense (1,000,000s) 2 15.5 20 When comparing the mean annual computer technology expense for companies in the tax services and education industries, which of the following 95% confidence interval can be constructed?arrow_forwardThe historical data of Velvetta Inc., a healthcare products manufacturer, have shown that in a production process for filling bottles of shampoo, variance in the volume is constant; however, clogs in the filling machine often affect the mean volume. The historical standard deviation is 5 milliliters. In filling 250-milliliter bottles, a sample of 20 found a mean volume of 242 milliliters. Velvetta Inc. Shampoo Production Alpha Value 0.05 Standard Deviation 5 Sample Size 20 Sample Mean 242 Based on the data in the table above, calculate the margin of error at 95% confidence interval. Open an Excel sheet to work on this problem. Show labelsarrow_forwardThe number of grants of carbohydrates contained 1-ounce servings of randomely selected chocolate and non-chocolate candy is listed below. Is there evidence to conclude that there is a difference between in mean carbohydrates between chocolate and non-chocolate candies? Use the unequal variance T-test and significant level =.05. Assume carbohydrates per serving is normally distributed for both types of candy. Chocolate:29,25,17,36,41,25,32,29,38,34,24,27,29 Non-chocolate: 41,41,37, 29,30,38,39,18,29,55,29 a.) State the null and alternative hypotheses. b.) Identify test statistic and p-value. c.) Make a decision, reject Ho or not? D.) Summarize the results in a sentence.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
The Shape of Data: Distributions: Crash Course Statistics #7; Author: CrashCourse;https://www.youtube.com/watch?v=bPFNxD3Yg6U;License: Standard YouTube License, CC-BY
Shape, Center, and Spread - Module 20.2 (Part 1); Author: Mrmathblog;https://www.youtube.com/watch?v=COaid7O_Gag;License: Standard YouTube License, CC-BY
Shape, Center and Spread; Author: Emily Murdock;https://www.youtube.com/watch?v=_YyW0DSCzpM;License: Standard Youtube License