second part of the same unit 3 project
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Looking at the relationship between each of the Five Quizzes and the Final Course Percent (variable name is “percent”): First, use (and include) SPSS to measure the relationship (correlation) between each Quiz and the Final Course Percent. Which of the five Quizzes has the weakest relationship (correlation) with the Final Course Percent, and how do you know? Which of the five Quizzes has the strongest relationship with the Final Course Percent, and how do you know?
Quiz 1 
Quiz 2 
Quiz 3 
Quiz 4 
Quiz 5 

Final Course Percent 
rvalue? 
rvalue? 
rvalue? 
rvalue? 
rvalue? 
For credit, you must post your SPSS output along with your responses to the question.
Step 1: Calculate five correlation coefficients in SPSS (Final course percent and Quiz 1, Final course percent and Quiz 2, Final course percent and Quiz 3, Final course percent and quiz 4, Final course percent and Quiz 5). Fill in the chart above with your solutions.
Step 2: Place your SPSS output for all calculations from step 1 below the chart.
Respond to the questions (in steps 3 – 4) below your SPSS output.
Step 3: Which of the five Quizzes has the weakest relationship (correlation) with the Final course percent, and how do you know?
Step 4: Which of the five Quizzes has the strongest relationship with Final course percent, and how do you know
Use SPSS to create the scatterplot for the Quiz and Final Course Percent that had the strongest relationship. Paste the graph here. What does this graph show or tell you? Is it linear? Is the slope positive (going upwards) or negative (going downwards)? Does it seem like doing well on the Quiz relates (or correlates) to doing well on the Final Course Points?
Step 1: Look back at your solutions to question 11. “Which of the five Quizzes has the strongest relationship (correlation) with the Final Course percent?” Use this quiz to create a scatterplot with total points. Paste the graph here.
Respond to questions (in Steps 2 – 5) below your scatterplot.
Step 2: What does this graph show or tell you?
Step 3: Is it linear?
Step 4: Is the slope positive (going upwards) or negative (going downwards)?
Step 5: Does it seem like doing well on the Quiz relates (or correlates) to doing well on the Final Course Percent?
. Will a low Quiz 1 score cause a student to get a low Final Course Percent? Why or why not – explain.
The key to answering this question is the word “cause.” Think about this… does correlation imply causation…?
(For Questions 1417 use the SPSS output below to determine the answers).
Which two variables are being investigated and label each variable as either dependent or independent.
Step 1: List the two variables – they are in the chart and on the graph.
Step 2: Label each variable as dependent or independent?
The Correlation Coefficient (or rvalue) is used to measure the relationship between any two variables. In this case, what is the rvalue?
The rvalue can be found in the chart above the graph.
What does the rvalue and the scatterplot tell you about the relationship between these two variables? Is the relationship positive or negative? Is it strong, medium, or weak?
Respond to this question by discussing the 1) strength and 2) direction of the rvalue from question 15. The strength qualifies the measure, for example, is the rvalue strong, moderate or weak? The direction is positive which corresponds to increasing, and negative which corresponds to decreasing. Here is a breakdown you can use to help with your response:
+1.0 perfect positive correlation
+0.8 strong positive correlation
+0.5 moderate positive correlation
+0.3 weak positive correlation
+ 0.1 very weak positive correlation
0 no correlation
0.1 very weak correlation
0.3 weak negative correlation
0.5 moderate negative correlation
0.8 strong negative correlation
1.0 perfect negative correlation
Suppose a student has a previous GPA of 3.12. Using the scatterplot, what is a good estimate of what their Total Points?
Look back at the scatterplot. Draw a vertical line up through the horizontal axis at 3.2. Find were a good estimate of final exam points is located on this vertical line. From this point draw a horizontal line over to the yaxis. What y–value are you at? This is your estimate. There is no one correct response. Answers will vary.