Exam (elaborations)
STAT CHAP 4.2 Questions and and answers (1)
- Course
- Institution
STAT CHAP 4.2 Questions and and answers (1)
[Show more]
Seller
Follow
lydiaomutho
Content preview
STAT CHAP 4.2Consider the data set given in the accompanying table. Complete parts(a) through
(c).
(b) Find the equation of the line containing the points
(−2,−2) and (2,5).
✅✅
(c) Graph the line found in part(b) on the scatter diagram. Choose the correct graph
below. - -D
The equation of the line is
y= 7/4x+ 3/2.
B
Suppose the line y=2.8333x−22.4967 describes the relation between theclub-head
speed(in miles perhour), x and the distance a golf ball travels(in yards), y.
(a) Predict the distance a golf ball will travel if theclub-head speed is 100 mph.
✅✅
(b) Suppose the observed distance a golf ball traveled when theclub-head speed
was 100 mph was 265 yards. What is theresidual? - -260.8
265-260.8=4.2
✅✅
Which of the following is true of theleast-squares regression line
y=b1x+b0? - -The sign of the linear correlationcoefficient, r, and the sign of the
slope of theleast-squares regressionline, b1, are the same.
Theleast-squares regression line always contains the point x,y.
The predicted value ofy, y, is an estimate of the mean value of the response variable
for that particular value of the explanatory variable.
Theleast-squares regression line minimizes the sum of squared residuals.
A pediatrician wants to determine the relation that exists between achild's height,x,
and headcircumference, y. She randomly selects 11 children from herpractice,
measures their heights and head circumferences and obtains the accompanying
data. Complete parts(a) through(e).
a) Find theleast-squares regression line treating height as the explanatory variable
and head circumference as the response variable.
, (b) Use the regression equation to predict the head circumference of a child who is
25 inches tall.
(c)Compute the residual based on the observed head circumference of the
25-inch-tall
child in the table. Is the head circumference of this child above average or
belowaverage?
d) Draw theleast-squares regression line on the scatter diagram of the data and
label the residual from part(c). Choose the correct graph below.
Is the head circumference of this child above average or belowaverage
-✅✅ -STAT-REGRESSION-LINEAR- COMPUTE FIND WHERE IT SAYS
INTERCEPT AND SLOPE
ENTER 25 FOR PERDICTED X
95% CI MEAN- PRED Y.
B
BELOW AVERAGE
For children who are 26.75 inchestall, head circumference varies.
A student at a junior college conducted a survey of 20 randomly selectedfull-time
students to determine the relation between the number of hours of video game
playing eachweek, x, andgrade-point average, y. She found that a linear relation
exists between the two variables. Theleast-squares regression line that describes
this relation is
y=−0.0578x+2.9274.
(a) Predict thegrade-point average of a student who plays video games 8 hours per
week.
b) Interpret the slope.
(c) Ifappropriate, interpret they-intercept.
(d) A student who plays video games 7 hours per week has agrade-point average of
2.63.
✅✅
Is thestudent's grade-point average above or below average among all students
who play video games 7 hours perweek? - -The predictedgrade-point average
is 2.47
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lydiaomutho. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
76462 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now