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[Midterm Q3] It behooves us as scientists to honor our forebears.   a. Name the man responsible for inventing the field of experimental design. b. Name where he worked when he developed the factorial design and ANOVA. c. During which decade did he discover the basic experimental design principles?

[Midterm Q5] Why is it wise to partition experimental resources into a series of smaller experiments rather than conduct a single large experiment?  Can you give an example of why sequential experiments might be wise or prudent?

[Midterm Q11 A, B, C, D, E]  A nickel-titanium alloy is used to make components for jet turbine aircraft engines. Cracking is a potentially serious problem in the final part, as it can lead to losing an engine in flight. A test is run at the parts producer to determine the effects of three factors on cracks. The three factors are pouring temperature (A), titanium content (B), heat treatment method (C).  Three replicates of a 23 design are run, and the length of crack (in μm) induced in a sample coupon subjected to a standard test is measured. The data are in the attached file Midterm11a.dxpx a.Estimate the factor effects. Which effects are large? b.Use the analysis of variance to confirm your conclusions for part (a). c.Write down a regression model for predicting length of cracks based on the results of this experiment.  You may cut & paste from DX. d.Analyze the residuals. Are there any obvious problems? e.Based on the analysis of main effects and interaction plots, what levels of A, B, and C would you recommend using, assuming small cracks are best?  

[Midterm Q10 D, E, F] Same bone loss treatment problem as described in problem 10 – this time to analyze results. In this problem you will find attached a Design Expert file named Midterm10d.dxpx. Use Design Expert to analyze the data found in this file. Is there evidence to support a claim that PEMF usage affects bone density loss? If so, determine which specific treatments reduce bone loss. Record your response to this question here. In the ANOVA table the PEMF P value for the this data set is? P= 0.NNNN.    e. If you find any outliers, assume they are from data entry errors and set them aside. What is the ANOVA table PEMF value for the revised data set? P= 0.NNNN. Does setting apart the outliers change your conclusion from part d? f. Are there any other problems with violations of assumptions from residual analysis?

Instacart is planning to obtain information about the “behavioral proclivities” of its major direct rivals in the food delivery service industry, such as Amazon Fresh and Shipt, by asking its top management team to use

[Midterm Q10 B, C] An article in Bioelectromagnetics (“Electromagnetic Effects on Forearm Disuse) describes a randomized, double-blind, placebo-controlled study to determine if a common pulsing electromagnetic field (PEMF) treatment could reduce bone loss after forearm disuse due to injury. Eighty injured subjects immobilized with a cast were randomly placed into four groups. A placebo or PEMF transmitter was worn on the injured forearm for 1, 2, or 4 hours per day for 8 weeks. The data below are the percent loss in forearm bone density (BD) after each patient’s treatment – with instructor modifications. Midterm Q10.png a. Suppose that the orthopedic surgeons consider 2.5% loss of bone density significant and historical data yields a bone loss standard deviation of roughly 1.5% in patients of this type.  Using these two numbers, comment on the use of 20 replicates per group: too big or too small? Use Design Expert.  Respond here with your answer and reason for it.   b. If you were seeking 95% power to detect the numbers mentioned in part a of this problem (2.5% / 1.5%), rebuild your Question 10 design and report the required number of replicates. Respond here with a number: “_________ replicates would be enough for approximately 95% power.”

[Midterm Q12 A, B, C] Reconsider the engine cracking problem experiment described in Problem 12. Suppose that the experimenter only performed the eight trials from replicate I. In addition, she ran four center points and obtained the following response values: 11.53, 12.81, 13.77, 14.41. I’ve included all the relevant data are in the attached file.  Analyze the data and answer the following questions: Midterm12a.dxpx a. Estimate the factor effects. Which effects are large? b. Use the analysis of variance to confirm your conclusions for part (a) and include a check for curvature. Does curvature seem significant? Why or why not? c. Based on this data set, write down a regression model for predicting crack length. Does this differ significantly from the 3 replicate model? That is, are the same factors with similar coefficient values driving the process?

[Midterm Q2] The Student t Test was the first experimental method to solving the basic test problem of comparing current vs. new product. a. Name the man responsible for inventing the Student t Test,  b. Name the company he worked for when he developed this test c. Name the decade he published the paper documenting this test (e.g. 1980’s)

[Midterm Q6] In the fall of 2012, my wife, Dr Deb Hutto, conducted experimental trials to prove her dissertation research proposal. Consider the case of teaching adult students attempting to earn a GED — students who already had unfavorable experiences with school. Dr Hutto theorized that teachers who involved the students in a learning community and encouraged them to believe in their ability to achieve would produce superior performing students over conventional methods. She was attempting to generate empirical evidence of the superiority of Motivational Systems Theory (MST) in a classroom setting. MST holds that properly taught students will be both more motivated and perform better academically. Dr Hutto was approved to conduct her experiment in 6 adult classes of approximately 10-15 students in three counties in northwest Florida. Dr Hutto randomly assigned conventional and motivational methods to six classrooms — three each — and measured student motivation and grade level both prior to the class and after the class. For example, student Jones might score 50 on a motivational questionnaire prior to class and 67 after – an improvement of 17 points in motivation or “self efficacy.” Similarly, Jones might move from grade level 6.8 to 8.3 in science during the semester, an improvement of 1.5 grade levels. For motivational classes, Dr Hutto spent two days teaching the instructors her methods. While she could control the teaching methods in each class, she was unable to randomly assign students to classes. She also worried about differences in the inherent teaching ability of the instructors for both classes. a. Can this be considered a designed experiment or is it something else? Why or why not? Recall Montgomery’s chapter 1 definition.b. Can this study establish a cause-and-effect link between teaching methods and student achievement?c. In an ideal world, describe at least two changes to a study like this to improve its worth as a designed experiment?

A nurse is providing discharge teaching to a client diagnosed with laryngitis. Which of the following instructions should the nurse include to promote recovery and comfort? Select all that apply.