Overview

This file contains a set of tasks that you need to complete in R for the lab assignment. The tasks may require you to add a code chuck, type code into a chunk, and/or execute code. Some tasks may also ask you to answer specific questions. Don’t forget that you need to acknowledge if you used any resources beyond class materials or got help to complete the assignment.

Additional information and examples relevant to this assignment can be found in the file “PlayingWithDataTutorial.html”.

The data set you will use is different than the one used in the instructions. Pay attention to the differences in the Excel files name, any variable names, and/or object names. You will need to adjust your code accordingly.

Once you have completed the assignment, you will need to knit this R Markdown file to produce an html file. You will then need to upload the .html file and this .Rmd file to AsULearn. Additionally, for this assignment you will upload the Excel file you created.

1. Add your name and the date

The first thing you need to do in this file is to add your name and date in the lines underneath this document’s title (see the code in lines 10 and 11).

2. Getting started

Insert a chunk of code in this section to identify and set your working directory and load packages. We will use the same three packages we did in the last lab: openxlsx, dplyr and tidyverse.

getwd()

## [1] "/Users/rlmcollins/Desktop"

setwd("/Users/rlmcollins/Desktop")

library("dplyr")

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

library("openxlsx")
library("tidyverse")

## ── Attaching core tidyverse packages ──────────────────────── tidyverse 2.0.0 ──
## ✔ forcats   1.0.0     ✔ readr     2.1.5
## ✔ ggplot2   3.5.2     ✔ stringr   1.5.1
## ✔ lubridate 1.9.4     ✔ tibble    3.3.0
## ✔ purrr     1.1.0     ✔ tidyr     1.3.1
## ── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag()    masks stats::lag()
## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors

3. Load Two Data Sets

Insert a chunk of code in this section to load your data. The Excel file for this assignment has two sheets: grades and attendance. Sheet 1 contains the grades data and Sheet 2 contains the attendance data. You will want to load each sheet into R as separate data objects. The name of the Excel file is different than what is in the instructions. Accordingly, you will need to adjust the code to read in the Excel file that was downloaded as part of the zip file.

GradeBook <- read.xlsx("GradeBook.xlsx" , sheet = 1)
head(GradeBook, 10)

##         X1 Midterm.1 Midterm.2 Assignment.1 Assignment.2 Assignment.3    Final
## 1     Noah  15.00000  12.00000     5.000000     8.000000     5.661442 30.00000
## 2     Jack  11.00478  15.00000     6.771172    10.000000     8.000000 26.00000
## 3    Emily  20.00000  20.00000     8.000000     8.000000     8.154995 20.00000
## 4    Colin  20.00000  17.00000     8.000000     5.000000     8.673615 25.00000
## 5   Hannah  10.00000  17.00000     6.802136     9.604730    10.000000 20.00000
## 6   Aubrie  20.00000  14.00000     5.000000     6.000000     6.000000 17.78453
## 7   Olivia  14.00000  17.72971    10.000000     7.000000     6.000000 26.00000
## 8   Duncan   9.62783  16.00000     7.000000     8.065708     8.000000 18.95910
## 9    Katie  19.00000  12.00000     9.000000     8.000000     8.967217 20.00000
## 10 Jackson  17.00000  15.00000     8.000000     6.000000     2.549882 25.00000

Attendance <- read.xlsx("GradeBook.xlsx" , sheet = 2)
head(Attendance, 10)

##       Name 1 2 3 4 5
## 1     Noah 1 1 1 1 1
## 2     Jack 0 1 1 1 1
## 3    Emily 1 1 0 0 1
## 4    Colin 1 0 1 1 1
## 5   Hannah 1 1 0 1 1
## 6   Aubrie 1 1 1 1 1
## 7   Olivia 1 1 1 1 1
## 8   Duncan 0 1 0 0 1
## 9    Katie 1 1 1 1 1
## 10 Jackson 1 0 1 1 1

4. Take a look at your data

Insert a chunk of code in this section and display the first 15 observations of each data set.

head("GradeBook, 10")

## [1] "GradeBook, 10"

tail("Attendance, 5")

## [1] "Attendance, 5"

5. Rename Variables

You will need to insert chunks of code and rename variables in your data sets in this section. I recommend trying to do only one thing per chunk of code.

In the attendance data set, you will need to rename the variables that are currently numbers into text. In the instructions, I called each variable Class and then the number of that class, for example Class1. Instead of using the same variable name as I did, you should call each variable a Meeting.

Attendance %>%
  rename(Meeting1 = "1",
         Meeting2 = "2",
         Meeting3 = "3",
         Meeting4 = "4",
         Meeting5 = "5") -> Attendance

head("Attendance, 10")

## [1] "Attendance, 10"

In the grade book data set, rename the variables so that they do not have a . in their names.

GradeBook %>%
  rename(Midterm1 = "Midterm.1",
         Midterm2 = "Midterm.2",
         Assignment1 = "Assignment.1",
         Assignment2 = "Assignment.2",
         Assignment3 = "Assignment.3",
         Final = "Final") -> GradeBook

head("GradeBook, 10")

## [1] "GradeBook, 10"

After renaming the variables, look at the first 15 observations for each data set.

head("Attendance, 10")

## [1] "Attendance, 10"

tail("GradeBook, 5")

## [1] "GradeBook, 5"

6. Creating New Attendance Variables

In this section, insert chunks and create the following variables in your attendance data set.

Total number of classes attended.

Attendance  %>%
  mutate(Present = (Meeting1 + Meeting2 + Meeting3 + Meeting4 + Meeting5)) -> Attendance

head("Attendance, 10")

## [1] "Attendance, 10"

Total number of classes absent. There are a total of 5 classes that students could potentially attend.

Attendance  %>%
  mutate(Absent = (Meeting1 + Meeting2 + Meeting3 + Meeting4 + Meeting5)) -> Attendance

head("Attendance, 10")

## [1] "Attendance, 10"

Total number of unexcused absences. Students are allowed up to 2 excused absences.

Attendance  %>%
  mutate(unexcusedabsences = (Meeting1 + Meeting2 + Meeting3 + Meeting4 + Meeting5)) -> Attendance

head("Attendance, 10")

## [1] "Attendance, 10"

Penalty on grade for unexcused absences. For each unexcused absence, a student’s grade will be penalized 0.5 points. Based on the number of unexcused absences, calculate the total penalty that should be applied to their grade.

After you have completed these calculations, take a look at the first 15 observations in your data set.

7. Create New Grade Variables

In this section, insert chunks and create the following variables in your grade book data set.

Each assignment in class is worth 10 points. Create a new variable for each assignment where you convert the raw score into a percentage.

GradeBook %>%
  mutate(PerA1 = (Assignment1/10)*100) -> GradeBook

print(GradeBook$Assignment1)

##  [1]  5.000000  6.771172  8.000000  8.000000  6.802136  5.000000 10.000000
##  [8]  7.000000  9.000000  8.000000  8.000000 10.000000  8.000000  6.000000
## [15]  6.000000  9.000000

GradeBook %>%
  mutate(PerA2 = (Assignment2/10)*100) -> GradeBook

print(GradeBook$Assignment2)

##  [1]  8.000000 10.000000  8.000000  5.000000  9.604730  6.000000  7.000000
##  [8]  8.065708  8.000000  6.000000 10.000000  9.000000 10.000000  7.000000
## [15]  8.000000  7.000000

GradeBook %>%
  mutate(PerA3 = (Assignment3/10)*100) -> GradeBook

print(GradeBook$Assignment3)

##  [1]  5.661442  8.000000  8.154995  8.673615 10.000000  6.000000  6.000000
##  [8]  8.000000  8.967217  2.549882  6.701154 10.000000 10.000000  8.000000
## [15]  6.000000  7.000000

Each midterm in the class is worth 20 points. Create a new variable for each midterm where you convert the raw score into a percentage.

GradeBook %>%
  mutate(PerMT1 = (Midterm1/20)*100) -> GradeBook

print(GradeBook$Midterm1)

##  [1] 15.00000 11.00478 20.00000 20.00000 10.00000 20.00000 14.00000  9.62783
##  [9] 19.00000 17.00000 11.00000 10.00000  7.00000 14.00000  6.00000 11.00000

GradeBook %>%
  mutate(PerMT2 = (Midterm2/20)*100) -> GradeBook

print(GradeBook$Midterm2)

##  [1] 12.00000 15.00000 20.00000 17.00000 17.00000 14.00000 17.72971 16.00000
##  [9] 12.00000 15.00000  9.93236 13.00000 11.00000 12.00000 10.00000 12.00000

The final exam is worth 30 points. Create a new variable for the final where you convert the raw score into a percentage.

GradeBook %>%
  mutate(PerF = (Final/30)*100) -> GradeBook

print(GradeBook$Final)

##  [1] 30.00000 26.00000 20.00000 25.00000 20.00000 17.78453 26.00000 18.95910
##  [9] 20.00000 25.00000 26.00000 26.00000 18.00000 29.00000 19.00000 28.00000

print(GradeBook$PerF)

##  [1] 100.00000  86.66667  66.66667  83.33333  66.66667  59.28176  86.66667
##  [8]  63.19701  66.66667  83.33333  86.66667  86.66667  60.00000  96.66667
## [15]  63.33333  93.33333

There are multiple ways one can calculate the overall grade for the class. You are going to calculate the final grade in two different ways.

You should provide equal weight to each item in the class regardless of the number of points it was originally worth. To do this, you should add together the percentage grades that you calculated and divide by 600 (you have 6 assignments, each one is worth up to 100 points once the grades were converted to percents).

GradeBook %>%
  mutate(OverallGrade = ((PerA1+PerA2+PerA3+PerMT1+PerMT2+PerF)/600*100)) -> GradeBook

print(GradeBook$OverallGrade)

##  [1] 70.26907 77.40038 84.70277 80.84491 77.62255 66.54696 79.21920 70.33221
##  [9] 80.22314 68.13869 73.05667 81.94444 71.66667 72.77778 57.22222 73.05556

You should weight items based on the number of points each was originally worth. The most straightforward way to do this is to add together the raw scores for each item and then divide by the total number of points possible. You already have the information you need to calculate the total number of points possible because you know how many points each type of assignment is worth and you know how many of each type of assignment is in the grade book.

GradeBook %>%
  mutate(OverallGrade = ((Assignment1+Assignment2+Assignment3+Midterm1+Midterm2+Final)/600*100)) -> GradeBook

print(GradeBook$OverallGrade)

##  [1] 12.610240 12.795993 14.025833 13.945602 12.234478 11.464088 13.454952
##  [8] 11.275440 12.827870 12.258314 11.938919 13.000000 10.666667 12.666667
## [15]  9.166667 12.333333

After you have completed these calucations, take a look at the first 15 observations in your data set.

8. Create Objects Containing a Single Value

In this section, insert chunks and calculate the mean, minimum, and maximum for 3 different variables (midterm 2, assignment 3, and the final exam) in the grade book data set. Use the variables that report the scores as a percentage that you created.

mean_PerMT1 <- mean(GradeBook$PerMT1)

print(mean_PerMT1)

## [1] 67.07269

min_PerMT1 <- min(GradeBook$PerMT1)
print(min_PerMT1)

## [1] 30

max_PerMT1 <- max(GradeBook$PerMT1)
print(max_PerMT1)

## [1] 100

9. Create Objects Containing Multiple Values

In this section, insert chunks and produce the following objects that will contain values for each variable in the data set.

Using the attendance data, create two objects. One object should contain the total number of students attending a class session. One object should contain the mean number of students attending a class session.

attendsum <- sapply(Attendance[ , c('Meeting1', 'Meeting2','Meeting3', 'Meeting4', 'Meeting5')], sum)

attendmean <- sapply(Attendance[ , c('Meeting1', 'Meeting2','Meeting3', 'Meeting4', 'Meeting5')], mean)

AttedanceSummary <- rbind(attendsum,attendmean)

print(AttedanceSummary)

##            Meeting1 Meeting2 Meeting3 Meeting4 Meeting5
## attendsum   13.0000  13.0000    12.00   14.000  15.0000
## attendmean   0.8125   0.8125     0.75    0.875   0.9375

Using the grade book data, create three objects for the mean, min, and max grades for each of the variable in the data set.

GradeBookmean <- sapply(GradeBook[ , c('Midterm1', 'Midterm2','Assignment1', 'Assignment2', 'Assignment3' , 'Final')], mean)

GradeBookmin <- sapply(GradeBook[ , c('Midterm1', 'Midterm2','Assignment1', 'Assignment2', 'Assignment3' , 'Final')], min)

GradeBookmax <- sapply(GradeBook[ , c('Midterm1', 'Midterm2','Assignment1', 'Assignment2', 'Assignment3' , 'Final')], max)

10. Combining Objects

In this section, insert chunks of code that will combine objects together.

Combine the two objects you created using the attendance data set in the last question into a single object. Print the object where you stored these objects.

attendsum <- sapply(Attendance[ , c('Meeting1', 'Meeting2','Meeting3', 'Meeting4', 'Meeting5')], sum)

attendmean <- sapply(Attendance[ , c('Meeting1', 'Meeting2','Meeting3', 'Meeting4', 'Meeting5')], mean)

AttedanceSummary <- rbind(attendsum,attendmean)

print(AttedanceSummary)

##            Meeting1 Meeting2 Meeting3 Meeting4 Meeting5
## attendsum   13.0000  13.0000    12.00   14.000  15.0000
## attendmean   0.8125   0.8125     0.75    0.875   0.9375

Combine the three objects you created using the grade book data set in the last question into a single object. Print the object where you stored these objects.

GradeBook <- rbind(GradeBookmin, GradeBookmean, GradeBookmax)

print(GradeBook)

##               Midterm1 Midterm2 Assignment1 Assignment2 Assignment3    Final
## GradeBookmin   6.00000  9.93236    5.000000    5.000000    2.549882 17.78453
## GradeBookmean 13.41454 13.97888    7.535832    7.916902    7.481769 23.42148
## GradeBookmax  20.00000 20.00000   10.000000   10.000000   10.000000 30.00000

11. Export Data Sets

In this section, insert a chunk of code to export the grade book data, the attendance data, the summary grade book, and the summary attendance as one Excel file. Make sure to name your data file something different than the Excel file that had the original data that you loaded into R for this assignment.

write.xlsx(AttedanceSummary, file = "AttendanceSummary.xlsx")

sheets<- list("Grades" = GradeBook, "Attendance" = Attendance, AttendanceSummary = "AttedanceSummary")

write.xlsx(sheets, file = "combined.xlsx")

12. Did you recieve help?

Enter the names of anyone one that assisted you with completing this lab. If no one helped you complete the assignment, just type out that no one helped you

Caitlyn Fiocchi

13. Did you provide anyone help with completing this lab?

Enter the names of anyone that you assisted with completing this lab. If you did not help anyone, then just type out that you didn’t help anyone. No

14. Knit the Document

Click the “Knit” button to publish your work as an html document. This document or file will appear in the folder specified by your working directory. You will need to upload both this RMarkdown file and the html file it produces to AsU Learn to get all of the lab points for this week. Additionally, you need to upload the Excel file that you exported when completing the assignment to get all of the lab points for this week.

PS/CJ3115 Fall 2025: Playing with Data

Raequel Collins

9/24/25