Need help with finding correlation coefficient.
COMPETENCY ASSESSMENT
Introduction Assessment Rubric and Minimum Submission Requirements
This competency assessment assesses the following Outcome(s):
MM207M3: Determine the relationship between two variables.
GEL-1.02: Demonstrate college-level communication through the composition of original materials in Standard English.
It is time to demonstrate what you have learned in this module! One of the concepts we covered in this module was the interpretation
and calculation of the relationship between any two variables. You will be required to calculate correlation coefficients. You will also be
required to interpret and compare relationships between pairs of variables using the associated correlation coefficients. You will be
required to create scatter plots and interpret scatter plots, such as whether the two variables in the scatter plot are related, the apparent
strength of the relationship, and whether the direction of the relationship is positive or negative. The assessment will also cover linear
regression. You will have to use regression equations for prediction and will have to understand and interpret such equations.
Throughout this module and on assessments, you are welcome to use Excel as you wish.
You will be completing the Competency Assessment in MyLab. You will be applying concepts from logic to answer the questions about
a variety of real life applications and situations.
Please note the following when completing the Competency Assessment:
The Competency Assessment must be completed in one sitting. You do not have the option to save and come back to finish the
assessment.
You have unlimited attempts to successfully complete the Competency Assessment.
The Competency Assessment will be manually scored by your instructor.
Within the Competency Assessment you will NOT find support resources, such as solved examples that were available in the
MyLab These support resources are not available in the Readiness or Competency Assessments.
Part 2
Excel is an excellent and powerful tool that can be used to investigate correlation and regression. For this assignment, complete the
following.
1. Choose any Excel dataset from Content > Course Resources. Include the name of the dataset. From that dataset, select any two
quantitative variables that you suspect will be related (such as age and height for example). What is the name of the dataset you
have chosen? Which two variables did you choose?
2. Next, using Excel, calculate the correlation coefficient (r value) between the two variables. Recall that the Excel “formula” for
correlation is “=CORREL”. What is the r value for the two variables that you have chosen? Is it positive or negative? Is it strong,
medium, or weak? Note that it is best to have an r value that is medium or strong. It is recommended that you try a few different
variables until you find two variables with an r value between .5 and 1 (or between -.5 and -1).
3. Next, use Excel to create a scatterplot for the two variables. You decide which variable will be dependent (y) and which will be
independent (x). On the scatterplot, include the “trendline” and the “equation for the line” using Excel options. Attach your
scatterplot to your post.
4. Finally, using the equation of the line that you generated above, substitute any reasonable value for x (your chosen independent
variable) and solve the equation for y (your chosen dependent variable). It is up to you to determine which of your two variables is x
and which is y. What prediction do you get? Show all of your work. In other words, type out the equation, substitute a value for x,
and show your solution for y.
5. Write 2 – 3 paragraphs that describe what your equation represents. Discuss which variable is the independent variable and which
is the dependent variable. Why do you think the dependent variable might “depend” on the independent variable? Explain how your
equation can be used to estimate values for the dependent variable. Finally, explain the difference between correlation and cause.
Give an example of two variables that are related, but are not causal. Your paragraphs should follow the conventions of Standard
English (correct grammar, punctuation, and spelling). Your writing should be well ordered, logical and unified, as well as original
and insightful. In addition to fulfilling the specifics of the Assignment, APA citation style* should be followed.
7/23/24, 10:18 AM
Page 1 of 2
You can find numerous APA resources in the Writing Center Writing Reference Library on the Research, Citation, and Plagiarism page
.
Submitting Your Assessment Part 2:
When you are ready to submit your Course Assessment Part 2, click on the Course Assessment Dropbox.
7/23/24, 10:18 AM
Page 2 of 2
