<< Chapter < Page Chapter >> Page >

Regression (fuel efficiency)

Class Time:

Names:

    Student learning outcomes

  • The student will calculate and construct the line of best fit between two variables.
  • The student will evaluate the relationship between two variables to determine if that relationship is significant.

Collect the data

Use the most recent April issue of Consumer Reports. It will give the total fuel efficiency (in miles per gallon) and weight (in pounds) of new model cars with automatic transmissions. We will use this data to determine the relationship, if any, between the fuel efficiency of a car and its weight.

  1. Using your random number generator, randomly select 20 cars from the list and record their weights and fuel efficiency into [link] .
    Weight Fuel Efficiency
  2. Which variable should be the dependent variable and which should be the independent variable? Why?
  3. By hand, do a scatterplot of “weight” vs. “fuel efficiency”. Plot the points on graph paper. Label both axes with words. Scale both axes accurately.
    Blank graph with vertical and horizontal axes.

Analyze the data

Enter your data into your calculator or computer. Write the linear equation, rounding to 4 decimal places.

  1. Calculate the following:
    1. a = ______
    2. b = ______
    3. correlation = ______
    4. n = ______
    5. equation: ŷ = ______
  2. Obtain the graph of the regression line on your calculator. Sketch the regression line on the same axes as your scatter plot.

    Discussion questions

  1. Is the correlation significant? Explain how you determined this in complete sentences.
  2. Is the relationship a positive one or a negative one? Explain how you can tell and what this means in terms of weight and fuel efficiency.
  3. In one or two complete sentences, what is the practical interpretation of the slope of the least squares line in terms of fuel efficiency and weight?
  4. For a car that weighs 4,000 pounds, predict its fuel efficiency. Include units.
  5. Can we predict the fuel efficiency of a car that weighs 10,000 pounds using the least squares line? Explain why or why not.
  6. Answer each question in complete sentences.
    1. Does the line seem to fit the data? Why or why not?
    2. What does the correlation imply about the relationship between fuel efficiency and weight of a car? Is this what you expected?
  7. Are there any outliers? If so, which point is an outlier?

Questions & Answers

why we learn economics ? Explain briefly
ayalew Reply
why we learn economics ?
ayalew
why we learn economics
ayalew
profit maximize for monopolistically?
Usman Reply
what kind of demand curve under monopoly?
Mik Reply
what is the difference between inflation and scarcity ?
Abdu Reply
What stops oligopolists from acting together as a monopolist and earning the highest possible level of profits?
Mik
why economics is difficult for 2nd school students.
Siraj Reply
what does mean opportunity cost?
Aster Reply
what is poetive effect of population growth
Solomon Reply
what is inflation
Nasir Reply
what is demand
Eleni
what is economics
IMLAN Reply
economics theory describes individual behavior as the result of a process of optimization under constraints the objective to be reached being determined by
Kalkidan
Economics is a branch of social science that deal with How to wise use of resource ,s
Kassie
need
WARKISA
Economic Needs: In economics, needs are goods or services that are necessary for maintaining a certain standard of living. This includes things like healthcare, education, and transportation.
Kalkidan
What is demand and supply
EMPEROR Reply
deman means?
Alex
what is supply?
Alex
ex play supply?
Alex
Money market is a branch or segment of financial market where short-term debt instruments are traded upon. The instruments in this market includes Treasury bills, Bonds, Commercial Papers, Call money among other.
murana Reply
good
Kayode
what is money market
umar Reply
Examine the distinction between theory of comparative cost Advantage and theory of factor proportion
Fatima Reply
What is inflation
Bright Reply
a general and ongoing rise in the level of prices in an economy
AI-Robot
What are the factors that affect demand for a commodity
Florence Reply
price
Kenu
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Introductory statistics. OpenStax CNX. May 06, 2016 Download for free at http://legacy.cnx.org/content/col11562/1.18
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Introductory statistics' conversation and receive update notifications?

Ask