What are the three conditions that need to be met before calculating/using the correlation coefficient?
Question 2
2.
Question 3
3.
Question 4
4.
A group of ten adults were studied. Their height, weight and age were recorded.
Use the following table with age and weight data to create a scatterplot in your Ti-84: stat, edit, L1 & L2,
then Statplot (2nd, y=), select the scatterplot, make sure plot #1 is ON, ZoomStat (#9).
Use the 'show your work' to roughly sketch the scatterplot using the scribble tool (second box in the tool bar on the left). You can increase the size/color of the dots with the top box in the tool bar.
Question 5
5.
Question 6
6.
A group of ten adults were studied. Their height, weight and age were recorded.
Using the scatterplot created for question #4, interpret the relationship between age and weight.
Question 7
7.
A group of ten adults were studied. Their height, weight and age were recorded.
Use the scatterplot from #4, is it appropriate to calculate the correlation coefficient?
Enter your answer as 'yes' or 'no'.
Question 8
8.
A group of ten adults were studied. Their height, weight and age were recorded.
Using the data from #4 and your Ti-84, calculate the correlation coefficient.
Stat, Calc, #8 LinReg (a+bx)
Enter your answer below, round the correlation coefficient to three places past the decimal.
Question 9
9.
A group of ten adults were studied. Their height, weight and age were recorded.
Use the following table with height and weight data to create a scatterplot in your Ti-84.
Use Xlist: L3 (2nd, 3) for the height data, keep Ylist the same.
Use the 'show your work' to roughly sketch the scatterplot using the scribble tool (second box in the tool bar on the left).
You can increase the size/color of the dots with the top box in the tool bar.
Question 10
10.
Question 11
11.
A group of ten adults were studied. Their height, weight and age were recorded.
Using the scatterplot created for question #9, interpret the relationship between age and weight.
Question 12
12.
A group of ten adults were studied. Their height, weight and age were recorded.
Use the scatterplot from #9, is it appropriate to calculate the correlation coefficient?
Enter your answer as 'yes' or 'no'.
Question 13
13.
A group of ten adults were studied. Their height, weight and age were recorded.
Using the data from #9 and your Ti-84, calculate the correlation coefficient.
Stat, Calc, #8 LinReg (a+bx)
Round the correlation coefficient to three places past the decimal.
Question 14
14.
Nearly Normal Condition
Outlier Condition
Categorical Variables Condition
Select the correlation values that show a weak condition:
Hint: there are 4
0.026
0.931
0.152
0.547
-0.813
-0.942
-0.143
-0.049
Select the correlation values that show a strong condition:
Hint: there are 3
0.026
0.931
0.152
0.547
-0.813
-0.942
-0.143
-0.049
A group of ten adults were studied. Their height, weight and age were recorded.
Using the scatterplot created for question #4, describe the relationship between age and weight.
Strong
Weak
Curved
Positive
Moderate
No Form
Negative
Linear
Scattered
As age increases, weight slightly decreases.
As age increases, weight strongly decreases.
As age increases, weight strongly increases.
A group of ten adults were studied. Their height, weight and age were recorded.
Using the scatterplot created for question #9, describe the relationship between height and weight.
Positive
Scattered
Negative
Linear
Curved
No Form
Strong
Weak
Moderate
As height increases, weight strongly decreases.
There is no relationship between height and weight.
As height increases, weight slightly increases.
Compare the correlation coefficients calculated in #8 & #13:
1. Which shows a stronger linear relationship?
2. How do you know?
Select two answers.
They can't be compared because the graphs compare different variables.
Height vs Weight shows a stronger relationship.
The correlation coefficients are equal.
The correlation coefficient (r) is closer to 0.
The correlation coefficient (r) is closer to +1.
Both scatterplots show the same strength linear relationships.