Colorado State University Global Campus Confidence Interval Estimate of the Differences Worksheet

1. Create an R script (*.R) file to calculate the 95% confidence interval estimate ofthe differences between 2 population means of statistical exam scores according
to the steps given below. Give the script file a name that includes your first name
and last name like this Solution-W1-FirstName-LastName.R.
Complete these steps:
Step 1
Include these 3 lines of comments at the beginning of your R (*.R) script file to document
the script:
# Name: Elizabeth Abrams
# Course: MIS446
# Module: 6
Step 2
A statistics instructor is concerned that after her students perform well on the first of
two major examinations in the introductory-level class, their performance appears to
drop off on the second. Since this pattern appears to repeat itself across many sections
of the same statistics class at her university, she wants to confirm that the downward
trend in performance on the two 100-point examinations is real. To this end, she collects
the examination results from a random sample of n = 12 students from the previous
academic year. The scores on Exam 1 are: 81, 89, 83, 81, 77, 82, 79, 88, 80, 81, 79, and
91. On Exam 2, they are: 78, 77, 69, 81, 78, 74, 76, 79, 83,
76, 79,and 74.
1.
I.
II.
Create an R data frame to organize this data into two variables and twelve
observations.
Calculate the point estimate of the difference between the two population
means.
Your R code should be well commented and well organized to explain what the code
does.
Step 3
Enter this Sys.time() R function to print the current date and time and this
Sys.getenv(“username”) R function to print your username as shown here:
Step 4
Calculate the 95% confidence interval estimate of the difference between the two
population means.
Your R code should be well commented and well organized to explain what the code
does.
Step 5
Enter this Sys.time() R function to print current date and time and this
Sys.getenv(“username”) R function to print your username as shown here:
2. Save and execute your *.R script file and display the results of its execution in the
RStudio console and/or the Plots tabs.
Take screenshots of your ordered steps to demonstrate successful completion of your
work. The screenshot should show the R commands you applied and the results you
obtained. Do not capture trial and error results. Only your final results should be
captured. Your screenshot(s) should look something like this:
3. Summarize your work on this assignment as follows:
o Explain how you completed this work and how you resolved the issues
you faced, if any. Explanation of your work should be relevant and
detailed.
o Interpret the results you obtained from your work. Interpretation of
results should be relevant and accurate.
o Reflect on your experience with this assignment and the lessons you
learned. Reflection on experience should be relevant and personalized.
To submit your response to this assignment:
1. Prepare all the required *.R script file and screenshots.
2. Prepare your summary of your work (what you did, interpretation of results, and
reflection).
3. Use the Submission Template – Assignment.docx Download Submission Template
– Assignment.docxdocument and complete all its sections from your prepared
screenshots and work summary.
4. Make sure your completed Submission Template – Assignment document
1. follows the order given in the submission template.
2. is at least 3-4 pages in length.
3. has embedded your *.R script file or you can submit your *.R script file
separately.
4. includes all screenshots in the same order of execution of your *.R script.
5. meets the APA labeling requirements for tables, figures, (including
screenshots), code, and math.
6. conforms to CSU Global Guide to Writing and APA.