Interpreting the value of r
Name:
Date:
Class:
A
Quick Questions
Shade in the A or B circle for each question.
1. A study finds r = 0.85 between hours studied and test score. What does this suggest?
2. Which r value shows a negative relationship?
3. Which r value shows the weakest relationship?
4. A student says r = 1.4 is a very strong relationship. Is this possible?
5. Which statement about r = -0.95 is correct?
B
Match the Pairs
Draw a line connecting each item on the left to its match on the right.
| Left column | Right column | |
|---|---|---|
| 1r = -0.92 | AA very weak relationship, so almost no linear pattern | |
| 2r = 0.08 | BThe sign shows only direction, not strength. -0.85 is close to -1, so it is a strong negative relationship. | |
| 3A positive r means both variables tend to rise together, and a value near 1 makes it strong | Cr = 0.88 | |
| 4The value of r can never be outside the range from -1 to 1 | D-1 <= r <= 1 | |
| 5r = -0.85, so the relationship is weak because it is negative | EA strong negative relationship: as one variable rises, the other tends to fall | |
| 6r = 0.05, so there is a strong positive relationship | F0.05 is very close to 0, so the relationship is very weak, not strong. The positive sign only shows direction. |
C
Definitions
-1 <= r <= 1
D
Fill in the Blanks
Complete each line of code by filling in the missing parts.
1.
-1 <= r <= _
2.
=IF(CORREL(B2:B9,C2:C9)>_,"Up","Down")
3.
=IF(___(D2)>0.7,"Strong","Weak")
4.
IF r < _ THEN
DISPLAY "Negative"
END IF
5.
r = 0.05 is close to 0, so it is ____
E
Spot the Error
Shade in the letter of the line that contains an error.
Question 1
A
r = 0.85
B
if r > 0.7:
C
print("Strong negative")
Question 2
A
r = -0.9
B
if r < 0:
C
print("Both rise together")
Question 3
A
r = 1.4
B
if r >= -1 and r <= 1:
C
print("Valid r value")
Question 4
A
r = 0.05
B
if abs(r) > 0.3:
C
print("Weak relationship")
Question 5
A
r = -0.8
B
strength = abs(r)
C
if strength > 0.7:
D
print("Weak negative")
Answer Key
Interpreting the value of r
Section A: Quick Questions
Q1
B — A strong positive relationship
Q2
A — r = -0.62
Q3
A — r = 0.05
Q4
A — No, r must stay between -1 and 1
Q5
B — Strong: as one variable rises, the other falls
Section B: Match the Pairs
Q1
r = -0.92 → A strong negative relationship: as one variable rises, the other tends to fall
Q2
r = 0.08 → A very weak relationship, so almost no linear pattern
Q3
A positive r means both variables tend to rise together, and a value near 1 makes it strong → r = 0.88
Q4
The value of r can never be outside the range from -1 to 1 → -1 <= r <= 1
Q5
r = -0.85, so the relationship is weak because it is negative → The sign shows only direction, not strength. -0.85 is close to -1, so it is a strong negative relationship.
Q6
r = 0.05, so there is a strong positive relationship → 0.05 is very close to 0, so the relationship is very weak, not strong. The positive sign only shows direction.
Section C: Definitions
Q1
-1 <= r <= 1 — r always sits from -1 to 1. The sign shows direction (+ rises together, - one rises as other falls). Close to 0 is weak; close to 1 or -1 is strong.Section D: Fill in the Blanks
Q1
-1 <= r <= 1Q2
=IF(CORREL(B2:B9,C2:C9)>0,"Up","Down")Q3
=IF(ABS(D2)>0.7,"Strong","Weak")Q4
IF r < 0 THEN
DISPLAY "Negative"
END IFQ5
r = 0.05 is close to 0, so it is weakSection E: Spot the Error
Q1
C — r = 0.85 is positive (above 0) and close to 1, so the relationship is strong and positive, not negative. It should print "Strong positive".
Q2
C — A negative r means one variable rises as the other falls. Both rising together describes a positive r. The line should print "One rises, other falls".
Q3
A — r can only be between -1 and 1, so 1.4 is impossible. The value must be within that range, for example r = 0.4.
Q4
B — A weak relationship has r close to 0, so abs(r) should be small. The test should be abs(r) < 0.3, not greater than 0.3.
Q5
D — r = -0.8 is close to -1, so the relationship is strong. Its size (0.8) is large, so it should print "Strong negative".