2.99 See Answer

Question: Consider the data of Table 17.1.

Consider the data of Table 17.1. Suppose that additional samples of size 5 are taken and tensile strength recorded. The sampling produces the following results (in pounds per square inch).
Consider the data of Table 17.1. Suppose that additional samples of size 5 are taken and tensile strength recorded. The sampling produces the following results (in pounds per square inch).


(a) Plot the data, using the ¯X - and R-charts for the preliminary data of Table 17.1.
(b) Does the process appear to be in control? If not, explain why.

(a) Plot the data, using the ¯X - and R-charts for the preliminary data of Table 17.1. (b) Does the process appear to be in control? If not, explain why.





Transcribed Image Text:

Sample R 1 1511 22 14 2 1508 3 1522 11 4 1488 18 5 1519 1524 11 1519 8 8 1504 7 9 1500 8 10 1519 14


> A carbon dioxide (CO2) flooding technique is used to extract crude oil. The CO2 floods oil pockets and displaces the crude oil. In an experiment, flow tubes are dipped into sample oil pockets containing a known amount of oil. Using three different values

> Consider the data of Review Exercise 12.64. Suppose it is of interest to add some “interaction” terms. Namely, consider the model yi = β0 + β1x1i + β2x2i + β3x3i + &Icirc

> In exercise physiology, an objective measure of aerobic fitness is the oxygen consumption in volume per unit body weight per unit time. Thirty-one individuals were used in an experiment in order to be able to model oxygen consumption against age in years

> In a chemical engineering experiment dealing with heat transfer in a shallow fluidized bed, data are collected on the following four regressor variables: fluidizing gas flow rate, lb/hr (x1); supernatant gas flow rate, lb/hr (x2); supernatant gas inlet n

> A small experiment was conducted to fit a multiple regression equation relating the yield y to temperature x1, reaction time x2, and concentration of one of the reactants x3. Two levels of each variable were chosen, and measurements corresponding to the

> Show that, in a multiple linear regression data set, hi =p. 2=1

> In the Department of Fisheries and Wildlife at Virginia Tech, an experiment was conducted to study the effect of stream characteristics on fish biomass. The regressor variables are as follows: average depth (of 50 cells), x1; area of in-stream cover (i.e

> In an experiment to ascertain the effect of load, x, in lb/inches2, on the probability of failure of specimens of a certain fabric type, an experiment was conducted in which numbers of specimens were exposed to loads ranging from 5 lb/in.2 to 90 lb/in.2.

> From a set of streptonignic dose-response data, an experimenter desires to develop a relationship between the proportion of lymphoblasts sampled that contain aberrations and the dosage of streptonignic. Five dosage levels were applied to the rabbits used

> The developer of a new condominium complex claims that 3 out of 5 buyers will prefer a two-bedroom unit, while his banker claims that it would be more correct to say that 7 out of 10 buyers will prefer a two bedroom unit. In previous predictions of this

> In Exercise 12.28, page 462, we have the following data concerning wear of a bearing: (a) The following model may be considered to describe the data: yi = β0 + β1x1i + β2x2i + β12x1ix2i + i, for i = 1, 2,

> For Exercise 12.57, test H0: β1 = β6 = 0. Give P-values and comment. Exercise 12.57: The pull strength of a wire bond is an important characteristic. The following data give information on pull strength y, die height x1, post he

> The pull strength of a wire bond is an important characteristic. The following data give information on pull strength y, die height x1, post height x2, loop height x3, wire length x4, bond width on the die x5, and bond width on the post x6. (From Myers,

> In an effort to model executive compensation for the year 1979, 33 firms were selected, and data were gathered on compensation, sales, profits, and employment. The following data were gathered for the year 1979. Consider the model yi = β0

> For the randomized block design with k treatments and b blocks, show that b. E(SSB) = (b – 1)o² + k B3. j=1

> Show that the computing formula for SSB, in the analysis of variance of the randomized complete block design, is equivalent to the corresponding term in the identity of Theorem 13.3.

> Prove Theorem 13.2.

> Show that the mean square error for the analysis of variance in a one-way classification is an unbiased estimate of σ2. SSE k(n – 1)

> Four different locations in the northeast were used for collecting ozone measurements in parts per million. Amounts of ozone were collected in 5 samples at each location. (a) Is there sufficient information here to suggest that there are differences i

> A study is conducted to compare gas mileage for 3 competing brands of gasoline. Four different automobile models of varying size are randomly selected. The data, in miles per gallon, follow. The order of testing is random for each model. (a) Discuss th

> A previous study indicates that the percentage of chain smokers, p, who have lung cancer follows a beta distribution (see Section 6.8) with mean 70% and standard deviation 10%. Suppose a new data set collected shows that 81 out of 120 chain smokers have

> A company that stamps gaskets out of sheets of rubber, plastic, and cork wants to compare the mean number of gaskets produced per hour for the three types of material. Two randomly selected stamping machines are chosen as blocks. The data represent the n

> An experiment was conducted to compare three types of paint for evidence of differences in their wearing qualities. They were exposed to abrasive action and the time in hours until abrasion was noticed was observed. Six specimens were used for each type

> In a study that was analyzed for personnel in the Department of Biochemistry at Virginia Tech, three diets were given to groups of rats in order to study the effect of each on dietary residual zinc in the bloodstream. Five pregnant rats were randomly ass

> Consider a design which is a 23−1 III with 2 center runs. Consider ¯yf as the average response at the design parameter and ¯y0 as the average response at the design center. Suppose the true regression model is E(Y ) = β0 + β1x1 + β2x2 + β3x3 + β11x21+ β2

> Construct a design that contains 9 design points, is orthogonal, contains 12 total runs and 3 degrees of freedom for replication error, and allows for a lack-of-fit test for pure quadratic curvature.

> Verify that your design in Review Exercise 15.43 is indeed resolution IV. Exercise 15.43: Use Table 15.16 to construct a 16-run design with 8 factors that is resolution IV. Table 15.16: Table 15.16: Some Resolution III, IV, V, VI and VII 2k-P Desi

> Use Table 15.16 to construct a 16-run design with 8 factors that is resolution IV. Table 15.16: Table 15.16: Some Resolution III, IV, V, VI and VII 2k-P Designs Number of Number of Factors Design Points Generators 23-1 2III C = ±AB D = ±ABC D = ±AB

> In the study “The Use of Regression Analysis for Correcting Matrix Effects in the X-Ray Fluorescence Analysis of Pyrotechnic Compositions,” published in the Proceedings of the Tenth Conference on the Design of Experime

> Use the data from Exercise 13.14 on page 530 to see if the median amount of nitrogen lost in perspiration is different for the three levels of dietary protein. Exercise 13.14: The study Loss of Nitrogen Through Sweat by Preadolescent Boys Consuming Thre

> In Review Exercise 13.45 on page 555, use the Kruskal-Wallis test, at the 0.05 level of significance, to determine if the chemical analyses performed by the four laboratories give, on average, the same results. Exercise 13.45: Four laboratories are bein

> Service calls come to a maintenance center according to a Poisson process with λ calls per minute. A data set of 20 one-minute periods yields an average of 1.8 calls. If the prior for λ follows an exponential distribution with mean 2, determine the poste

> A study by a chemical company compared the drainage properties of two different polymers. Ten different sludges were used, and both polymers were allowed to drain in each sludge. The free drainage was measured in mL/min. (a) Use the sign test at the 0.

> In the article called “Risky Assumptions” by Paul Slovic, Baruch Fischoff, and Sarah Lichtenstein, published in Psychology Today (June 1980), the risk of dying in the United States from 30 activities and technologies is ranked by members of the League of

> Two judges at a college homecoming parade rank eight floats in the following order: (a) Calculate the rank correlation coefficient. (b) Test the null hypothesis that ρ = 0 against the alternative that ρ > 0. Use α

> A consumer panel tests nine brands of microwave ovens for overall quality. The ranks assigned by the panel and the suggested retail prices are as follows: Is there a significant relationship between the quality and the price of a microwave oven? Use a

> With reference to the weights and chest sizes of infants in Exercise 11.47 on page 436, (a) calculate the rank correlation coefficient; (b) test the hypothesis, at the 0.025 level of significance, that ρ = 0 against the alternative that Ï

> Calculate the rank correlation coefficient for the daily rainfall and amount of particulate removed in Exercise 11.13 on page 400. Exercise 11.13: A study of the amount of rainfall and the quantity of air pollution removed produced the following data:

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> The following table gives the recorded grades for 10 students on a midterm test and the final examination in a calculus course: (a) Calculate the rank correlation coefficient. (b) Test the null hypothesis that ρ = 0 against the alternative t

> What is the probability that at least 95% of a population will exceed the smallest value in a random sample of size n = 135?

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> Repeat Exercise 18.2 when 1 of the next 4 drinks overflows and the uniform prior distribution is π(p) = 10, 0.05 < p < 0.15. Exercise 18.2: Let us assume that the prior distribution for the proportion p of drinks from a vending machine that overflow is

> What is the probability that the range of a random sample of size 24 includes at least 90% of the population?

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> Samples of size 50 are taken every hour from a process producing a certain type of item that is considered either defective or not defective. Twenty samples are taken. (a) Construct a control chart for control of proportion defective. (b) Does the proces

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> Consider the situation of Example 17.2. The following data are taken on additional samples of size 5. Plot the &Acirc;&macr;X - and S-values on the &Acirc;&macr;X - and S-charts that were produced with the data in the preliminary sample. Does the process

> Consider an in-control process with mean μ = 25 and σ = 1.0. Suppose that subgroups of size 5 are used with control limits μ ± 3σ/ √ n, and centerline at μ. Suppose that a shift occurs in the mean, and the new mean is μ = 26.5. (a) What is the average nu

> For the situation of Review Exercise 17.2, give numerical estimates of the mean and standard deviation of the diameter for the part being manufactured in the process. Exercise 17.2: Consider the following data taken on subgroups of size 5. The data cont

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> In Case Study 15.2 involving the coal cleansing data, the percent solids in the process system is known to vary uncontrollably during the process and is viewed as a noise factor with mean 0 and variance&Iuml;&#131;2z . The response, cleansing efficiency,

> Consider Case Study 15.1 involving the injection molding data. Suppose mold temperature is difficult to control and thus it can be assumed that in the process it follows a normal distribution with mean 0 and variance &Iuml;&#131;2z. Of concern is the var

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> A silver-plating process is used to coat a certain type of serving tray. When the process is in control, the thickness of the silver on the trays will vary randomly following a normal distribution with a mean of 0.02 millimeter and a standard deviation o

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> In a metallurgy experiment, it is desired to test the effect of four factors and their interactions on the concentration (percent by weight) of a particular phosphorus compound in casting material. The variables are A, percent phosphorus in the refinemen

> For Exercise 15.27, give all aliases for the six main effects. Exercise 15.27: There are six factors and only eight design points can be used. Construct a 26−3 by beginning with a 23 and use D = AB, E = −AC, and F = BC as the generators.

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2.99

See Answer