An article in the Journal of the Environmental Engineering Division ("Least Squares Estimates of BOD Parameters," Vol. 106, 1980, pp.1197-1202) describes the results of testing a sample from the Holston River below Kingport, TN, during August 1977. Thebiochemical oxygen demand (BOD) test is conducted over a period of time in days. The resulting data is shown below:Time (days) BOD (mg/liter)10.620.741.51.982.1102.6122.9143.7163.5183.7203.8Minitab output resulting from fitting a simple linear regression model with time as the explanatory variable and BOD as the responsefollows.PredictorCoefSE CoefTPConstant0.65780.16573.970.003Time0.178060.0140012.720.000S= 0.287281 R-Sq = 94.7% R-Sq(adj) = 94.1%Analysis of VarianceSourceDFSMSFPRegression113.34413.344161.690.000Residual90.7430.083ErrorTotal1014.087(a) Assuming that a simple linear regression model is appropriate, estimate the regression model relating BOD (y) to the time (x).Round your final answers to 4 decimal places.What is the estimate of a?Round your final answer to 3 decimal places. Round your final answer to 3 decimal places.(b) What is the estimate of expected BOD level when the time is 13 days?Round your final answer to 3 decimal places.(c) What change in mean BOD is expected when the time increases by 2 days?Round your final answer to 4 decimal places.(d) Suppose the time used is 2 days. Calculate the fitted value of y and the corresponding residual.Round your final answers to 4 decimal places.ŷ = i(e) The following is a graph of ŷ versus the corresponding observed values y;-Scatterplot of fitted vs BOD45-4.03.5-30252015100.5101.5203035BODWhich of the following describes what this plot would look like if the relationship between y and x was a deterministic (no randomerror) straight line?the points would be in a completely random patternthe points would all be equalO the points would fall on a horizontal lineO the points would fall along a 45° line(f) Does the plot actually obtained indicate that time is an effective regressor variable in predicting BOD?pauyO O

Solution: Note: Hello! As you have posted more than 3 sub parts, we are answering the first 3…

Answered: An article in the Journal of the…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

An article contained the following observations on degree of polymerization for paper specimens for which viscosity times concentration fell in a certain middle range: 415 420 422 423 426 429 432 435 436 439 446 447 448 452 459 463 464 (a) Construct a boxplot of the data. 420 430 440 450 460 420 430 440 450 460 420 430 440 450 460 420 430 440 450 460 Comment on any interesting features. (Select all that apply.) There are no outliers. There is little or no skew. There is one outlien The data is strongly skewed. The data appears to be centered near 439. The data appears to be centered near 429. (b) Is it plausible that the given sample observations were selected from a normal distribution? O Yes ○ No (c) Calculate a two-sided 95% confidence interval for true average degree of polymerization. (Round your answers to two decimal places.) Does the interval suggest that 445 is a plausible value for true average degree of polymerization? O Yes ○ No Does the interval suggest that 451 is a…
Scientists are looking at the effects of global warming on clutches of sea turtle hatchlings in different parts of the world. The data below has been collected: 1.Temperature of Incubation (in Kelvin) 2. Gender Group of Hatchling Clutch (0=0% male; 1= greater than 0% but less than or equal to 10% male; 2= greater than 10% but less than 20% male; 3= greater than 20% but less than or equal to 30% male and so on) 3. Number of hatched eggs 4. number of unhatched eggs 5. Location of Turtles (0=west North America; 1= west South America; 2= tropical regions of Pacific; 3= northwestern Atlantic; 4= Indian Ocean Which of the above variables are measured using a nominal scale, ordinal scale and ratio scale. (An answer can be none of variables) thank you
Please use the accompanying Excel data set or accompanying Text file data set when completing the following exercise. An article in Urban Ecosystems, "Urbanization and Warming of Phoenix (Arizona, USA): Impacts, Feedbacks and Mitigation" (2002, Vol. 6, pp. 183–203), mentions that Phoenix is ideal to study the effects of an urban heat island because it has grown from a population of 300,000 to approximately 3 million over the last 50 years and this is a period with a continuous, detailed climate record. The 50-year averages of the mean annual temperatures at eight sites in Phoenix are shown below. Check the assumption of normality in the population with a probability plot. Construct a 95% confidence interval for the standard deviation over the sites of the mean annual temperatures. Site Sky Harbor Airport 23.3 Average Mean Temperature (°C) Phoenix Greenway 21.7 Phoenix Encanto Waddell 21.6 21.7
Wild irises are beautiful flowers found throughout the United States, Canada, and northern Europe. This problem concerns the length of the sepal (leaf-like part covering the flower) of different species of wild iris. Data are based on information taken from an article by R. A. Fisher in Annals of Eugenics (Vol. 7, part 2, pp. 179 -188). Measurements of sepal length in centimeters from random samples of Iris setosa (I), Iris versicolor (II), and Iris virginica (III) are as follows below. I II III 5.9 5.8 6.9 4.8 6.5 5.6 4.6 6.4 4.9 5.7 4.3 7.7 4.8 5.8 5.6 5.4 6.3 6.3 5.8 5.5 6.6 Shall we reject or not reject the claim that there are no differences among the population means of sepal length for the different species of iris? Use a 5% level of significance. (b) Find SSTOT, SSBET, and SSW and check that SSTOT = SSBET + SSW. (Use 3 decimal places.) SSTOT = SSBET = SSW = Find d.f.BET, d.f.W, MSBET, and MSW. (Use 4 decimal places for MSBET, and…
An article contained the following observations on degree of polymerization for paper specimens for which viscosity times concentration fell in a certain middle range: 415 421 422 423 426 429 431 434 436 439 445 446 448 453 455 463 464 (a) Construct a boxplot of the data. O 420 420 430 430 440 440 450 The data appears to be centered near 438. The data is strongly skewed. There is one outlier. 450 Comment on any interesting features. (Select all that apply.) There are no outliers. The data appears to be centered near 428. There is little or no skew. 460 420 420 430 430 (b) Is it plausible that the given sample observations were selected from a normal distribution? Yes No 440 440 450 450 460 460 (c) Calculate a two-sided 95% confidence interval for true average degree of polymerization. (Round your answers to two decimal places.)
Please use the accompanying Excel data set or accompanying Text file data set when completing the following exercise. An article in Wood Science and Technology, "Creep in Chipboard, Part 3: Initial Assessment of the Influence of Moisture Content and Level of Stressing on Rate of Creep and Time to Failure" (1981, Vol. 15, pp. 125-144) studied the deflection (mm) of particleboard from stress levels of relative humidity. Assume that the two variables are related according to the simple linear regression model. The data are shown below x = Stress level (%) 54 54 61 61 68 68 75 75 75 y = Deflection (mm) 16.473 18.693 14.305 15.121 13.505 11.64 11.168 12.534 11.224 a. Calculate the least square estimates of the intercept (a) and slope (b). What is the estimate of o² (c)? b. Find the estimate of the mean deflection if the stress level can be limited to 66% (d). c. Estimate the change in the mean deflection associated with a 8% increment in stress level (e). (a) i (Round your answer to 2…
A survey collects demographic, socioeconomic, dietary, and health-related information on an annual basis. Here is a sample of 20 observations on HDL cholesterol level (mg/dl) obtained from the survey (HDL is "good" cholesterol; the higher its value, the lower the risk for heart disease). 36 46 38 48 51 53 66 50 50 85 37 45 32 38 44 62 94 34 29 47 (a) Calculate a point estimate (in mg/dl) of the population mean HDL cholesterol level. 49.5 mg/dl (b) Making no assumptions about the shape of the population distribution, calculate a point estimate (in mg/dl) of the value that separates the largest 50% of HDL levels from the smallest 50%. 44 X mg/dl (c) Calculate a point estimate (in mg/dl) of the population standard deviation. (Round your answer to three decimal places.) 18.46 X mg/dl (d) An HDL level of at least 60 is considered desirable as it corresponds to a significantly lower risk of heart disease. Making no assumptions about the shape of the population distribution, estimate the…
c)
Wild irises are beautiful flowers found throughout the United States, Canada, and northern Europe. This problem concerns the length of the sepal (leaf-like part covering the flower) of different species of wild iris. Data are based on information taken from an article by R. A. Fisher in Annals of Eugenics (Vol. 7, part 2, pp. 179 -188). Measurements of sepal length in centimeters from random samples of Iris setosa (I), Iris versicolor (II), and Iris virginica (III) are as follows below. I II III 5.9 5.5 6.7 4.1 6.8 5.8 5.2 6.5 4.5 5.4 4.5 7.2 4.1 5.4 5.2 5.2 6.2 6.9 5.6 5.2 6.7 Shall we reject or not reject the claim that there are no differences among the population means of sepal length for the different species of iris? Use a 10% level of significance. (a) What is the level of significance? 0.01 State the null and alternate hypotheses. O H,: H1 = H, = Hzi H;: All three means are different. O H,: H1 = H2 = Hzi H;: Exactly two means are equal. O H,: H, = H2 = Hai H,: At least two…
The toco toucan, the largest member of the toucan family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, such as being a refined adaptation for feeding. However, the large surface area may also be an important mechanism for radiating heat (and hence cooling the bird) as outdoor temperature increases. Presented is the data for beak heat loss, as a percent of total body heat loss from all sources, at various temperatures in degrees Celsius. [Note: The numerical values in this problem have been modified for testing purposes.] Temperature (°C) 1515 1616 1717 1818 1919 2020 2121 2222 2323 2424 2525 2626 2727 2828 2929 3030 Percent heat loss from beak 3232 3636 3636 3333 3535 4747 5757 5151 4242 5353 4646 5252 5959 5959 6363 6262 (a) What is the equation of the least‑squares regression line for predicting beak heat loss, as a percent of total body heat loss from all sources, from temperature? (Use…
High Cholesterol: A group of eight individuals with high cholesterol levels were given a new drug that was designed to lower cholesterol levels. Cholesterol levels, in milligrams per deciliter, were measured before and after treatment for each individual, with the following results: Individual Before After 1 237 208 2 239 202 3 230 185 4 245 217 5 242 180 6 282 215 7 243 182 8 286 195 Send data to Excel Part: 0 / 2 Part 1 of 2 (a) Construct a 99.9% confidence interval for the mean reduction in cholesterol level. Let d represent the cholesterol level before treatment minus the cholesterol level after. Use the TI-84 calculator and round the answers to at least one decimal place.
An article in the ACI Materials Journal (Vol. 84, 1987, pp. 213-216) describes several experiments investigating the rodding of concrete to remove trapped air. A 3-inch x 6-inch cylinder was used, and the number of times this rod was used is the design variable. The resulting compressive strength of the concrete specimen is the response. The data are shown in the following table. Compressive Strength (psi) Observations Rodding Level 10 15 20 25 1530 1530 1440 1610 1650 1500 1560 1730 1530 1500 1490 1510 (a) Is there any difference in compressive strength due to the rodding level? Use a = 0.05. Calculate to 2 decimal places for Is there statistical evidence to say that rodding level affects compressive strength? (b) Find to 2 decimal places the P-value for the F-statistic computed in part (a). P-value= (c) Analyze the following residual plots to determine model adequacy, Does the assumption of normality seem reasonable? Does there appear to be an outlier in the data? Does the assumption…

SEE MORE QUESTIONS

Recommended textbooks for you

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

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

SEE MORE TEXTBOOKS