NEW
Font size
WorksheetsLinear Regression and Correlation Practice
Total questions: 14
Worksheet time: 14mins
Estimate the correlation coefficient for this scatterplot.
r = 1.2
r = 0.89
r = 0
r = -0.89
what is the formula for linear regression?
y=mx+b
a^2+b^2=c^2
y1~mx1+b
(1/2)(b)(h)
What letter do we use to represent correlation coefficient?
c
r
p
h
The scatter plot below shows the number of books read by students in Mrs. Hall’s English class and their final grades. Which statement represents the best description about the line of best fit?
The more books students read, the lower their English grade.
The more books students read, the higher their English grade.
The fewer books students read, the higher their English grade.
No relationship exists between the number of books students read and their English grades.
Data is analyzed comparing hours studied and grades. It is determined that the correlation coefficient is 0.92. What does this mean?
There is a strong positive correlation between studying and grades.
There is a strong negative correlation between studying and grades.
There is a weak positive correlation between studying and grades.
There is a weak negative correlation between studying and grades.
Mr. Fisher is a really nice person (sometimes). He wants to buy his roommates ice cream. The regression equation that goes along with this situation is y∼2.95x+4.95 where x is the number of roommates who want ice cream and y is the total cost. What does the slope represent in this context?
m is 2.95
Mr. Fisher has to spend $4.95
For every 1 roomate who wants ice cream, the cost goes up $2.95.
For every 1 roommate who wants ice cream, the cost goes up $4.95
Mr. Fisher is a really nice person (sometimes). He wants to buy his roommates ice cream. The regression equation that goes along with this situation is y∼2.95x+4.95 where x is the number of roommates who want ice cream and y is the total cost. What does the y-intercept represent in this context?
If no roommates want ice cream, Mr. Fisher is going to spend $4.95 on himself.
If no roommates want ice cream, Mr. Fisher is going to spend $2.95
For every 1 roomate who wants ice cream, the cost goes up $2.95.
For every 1 roommate who wants ice cream, the cost goes up $4.95
Estimate the correlation coefficient for this scatterplot.
r = -0.9
r = 1
r = 0.9
r = -1
In a statistics course, a linear regression equation was computed to predict the final-exam score from the score on the first test. The equation was ŷ = 10 + 0.9x where y is the final exam score and x is the score on the first test. Carla scored 95 on the first test. What is the predicted value of her score on the final exam?
85.5
90
95
95.5
none of these
A set of data describes the relationship between the size of annual salary raises and the performance ratings for employees of a certain company. The least squares regression equation is ŷ = 1400 + 2000x where y is the raise amount (in dollars) and x is the performance rating. Which of the following statements must be true?
For each one-point increase in performance rating, the raise will increase on average by$2000.
The actual relationship between salary raises and performance rating is linear.
The residuals for half the observations in the dataset will be positive.
The correlation between salary raise and performance rating is negative.
For each one-point increase in performance rating, the raise will increase on average by$1400.
Mr. Nerdly asked the students in his AP Statistics class to report their overall grade point averages and their SAT Math scores. The scatterplot below provides information about his students’ data. The dark line is the least-squares regression line for the data, and its equation isŷ = 410.54 + 67.3x
Which of the following statements about the circled point is true? (click on the picture to enlarge)
Removing this student's data point would increase the slope of the least squares regression line (make it more steep)
If we used the least-squares line to predict this student’s SAT Math score, we would make a prediction that is too low.
This student’s residual is positive.
Removing this data point would not change the correlation between SAT math score and GPA.
Removing this student’s data point would decrease the slope of the least-squares line (make it less steep)
The equation of the best-fit line is
y(hat) = 1.3 + 0.73x. What is the residual for the point (4, 7)?
2.78
3.00
4.00
4.22
What is the best definition of the least squares regression line?
The line that minimizes the squares of the horizontal distances between the data points and the line.
The line that minimizes the squares of the vertical distances between the data points and the line.
The line that minimizes the vertical distances between the data points and the line.
The line that passes through the most number of data points.
An influential point in the context of least square regression lines is a
point far from all the other points
point that, when omitted, causes the line to change significantly
point that all other points are centered around
None of these
