Assignment 12 - QUESTIONS (1)
pdf
keyboard_arrow_up
School
Arizona State University *
*We aren’t endorsed by this school
Course
1271
Subject
Aerospace Engineering
Date
Feb 20, 2024
Type
Pages
4
Uploaded by AdmiralMusicParrot24
Assignment 12 — Problems @ 12.20 RANKINGS OF RESEARCH UNIVERSITIES. TOPUNIV Refer to the College Choice 2018 Rankings of National Research Universities, Exercise 11.2910 (p. 643). Data on academic reputation score, average financial aid awarded, average net cost to attend, median salary during early career, percentage of alumni who feel their work makes a better place, and percentage of science, technology, engineering, and math (STEM) degrees awarded for the top 50 research universities are saved in the file. (Information on selected schools are reproduced in the table below.) Consider a first-order multiple regression model to predict academic reputation score (y) using financial aid awarded (), net cost (z5), early career salary (z3), work makes a better place percentage (z,), and percentage of STEM degrees (z5). Data for Exercise 12.2018 (selected observations) Rank Academic Financial Cost Early Better STEM University Rep. Aid Pay Place Score 1 Yale Private 98 $42,792 $16,528 $70,300 53 22 2 Private 99 $41,505 $16,445 $74,800 54 19 Harvard 22 Public 76 $18,236 $13,463 $64,500 46 23 Virginia 23 Emory Private 77 $30,768 $27,412 $62,000 44 20 24 UCLA Public 76 $17,703 $13,686 $62,000 48 31 49 Public 56 $10,902 $13,541 $60,900 48 38 Purdue 50 Texas Public 55 $10,034 $11,323 $60,600 53 30 A&M
. Use statistical software to fit the model to the data. Give the least squares prediction equation. . Find and give a practical interpretation of the standard deviation of the model, s. . Find and give a practical interpretation of the coefficient of determination, R2. . Conduct a test of the overall adequacy of the model using a = .05. . Find a 90% confidence interval for the 8 coefficient associated with work makes a better place percentage (z4). Interpret the result.
@ 12.164 COOLING METHOD FOR GAS TURBINES. Refer to the Journal of GASTRB Engineering for Gas Turbines and Power (January 2005) study of a high-pressure inlet fogging method for a gas turbine engine, Exercise 7.13110 (p. 426). Recall that the heat rate (kilojoules per kilowatt per hour) was measured for each in a sample of 67 gas turbines augmented with high-pressure inlet fogging. In addition, several other variables were measured, including cycle speed (revolutions per minute), inlet temperature (°C), exhaust gas temperature (°C), cycle pressure ratio, and air mass flow rate (kilograms per second). The data are saved in the file. (The first and last five observations are listed in table below.) 14,000 12.2 950 446 15 13,196 17,384 14.8 1,149 537 20 11,948 11,085 11.8 1,024 478 27 11,289 14,045 13.2 1,149 553 29 11,964 18,910 14.0 1,066 532 8 12,766 3,600 35.0 1,288 448 152 8,714 3,600 20.0 1,160 456 84 9,469 16,000 10.6 1,232 560 14 11,948 14,600 13.4 1,077 536 20 12,414 Source: Based on R. Bhargava and C. B. Meher-Homji, “Parametric Analysis of Existing Gas Turbines with Inlet Evaporative and Overspray Fogging,” Journal of Engineering for Gas Turbines and Power, Vol. 127, No. 1, January 2005, pp. 145-158.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
a. Write a first-order model for heat rate (y) as a function of speed, inlet temperature, exhaust temperature, cycle pressure ratio, and airflow rate. b. Fit the model to the data using the method of least squares. c. Give practical interpretations of the 3 estimates. d. Find the model standard deviation, s, and interpret its value. e. Conduct a test for overall model utility using a = .01. f. Find and interpret RZ. g. Is there sufficient evidence (at @ = .01) to indicate that heat rate (y) is linearly related to inlet temperature? h. Find and interpret a 95% prediction interval for y when speed=7500, inlet temperature=1000, exhaust temperature=525, CP ratio=13.5, and airflow rate=10. (11,599.6, 13,665.5) i. Find and interpret a 95% confidence interval for E(y) when speed = 7500, inlet temperature = 1000, exhaust temperature = 525, CP ratio = 13.5, and airflow rate = 10.