Unit 2: Rtutorial

Author

Karla Bryant

Week 6: Working with Data

In the previous R tutorial, we started to work on science classroom dataset. We applied the data intensive research steps to explore our data and investigate the relationship between students’ grades and time-spent.

Let’s remember which libraries and functions we used!

Your Turn:

Please write down one or two sentence to explain why and how we use the following libraries and functions.

  1. tidyverse: It is a collection of packages. It makes it easier to read and write code because its more consistent.

  2. skimr: It gives you easy to read tables.

  3. ggplot: This is a package to create graphs.

  4. read_csv(): A function to import comma separated values (CSV) into R.

  5. view(): Used to open your data in a new tab.

  6. glimpse(): Gives a quick view of a dataset.

  7. head(): This shows the top rows of a dataset.

  8. tail(): This shows the last few rows of a dataset.

  9. select(): This is used to choose a specific column of data in a dataset.

  10. filter(): This is used to keep the rows where the condition input is true.

  11. arrange(): Places the dataset in order. The data goes in ascending order, from smallest to largest.

  12. desc(): Places the dataset in order. The data goes from largest to smallest.

  13. geom_histogram(): This is a ggplot2 function used to create histograms.

  14. geom_point(): This plots points on a graph to show the relationship between points.

Load the Tidyverse Package

Let’s start our R code along by loading the tidyverse package.

library(tidyverse)
── Attaching core tidyverse packages ──────────────────────── tidyverse 2.0.0 ──
✔ dplyr     1.1.4     ✔ readr     2.1.6
✔ forcats   1.0.1     ✔ stringr   1.6.0
✔ ggplot2   4.0.1     ✔ tibble    3.3.1
✔ lubridate 1.9.4     ✔ tidyr     1.3.2
✔ purrr     1.2.1     
── 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

Load the online science class data

Now, load the online science class data from the data folder and assign your data to a new object.

library(readr)
sci_online<- read_csv("~/ETR LA/Rtutorial-2 2/Rtutorial-2/Data/sci-online-classes.csv")
Rows: 603 Columns: 30
── Column specification ────────────────────────────────────────────────────────
Delimiter: ","
chr  (6): course_id, subject, semester, section, Gradebook_Item, Gender
dbl (23): student_id, total_points_possible, total_points_earned, percentage...
lgl  (1): Grade_Category

ℹ Use `spec()` to retrieve the full column specification for this data.
ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.
View(sci_online)

You loaded the data, now what should we do?

view(sci_online)

Your Turn:

Examine the contents of sci_classes in your console. You should type the object name to the console and check that.

Question: Is your object a tibble? How do you know?

Your response here: Yes, the object is a tibble because it displays in rows and columns of data.

Hint: Check the output in the console.

Check your data with different functions

You can check your data with different functions. Let’s remember how we use different functions to check our data.

glimpse(sci_online)
Rows: 603
Columns: 30
$ student_id            <dbl> 43146, 44638, 47448, 47979, 48797, 51943, 52326,…
$ course_id             <chr> "FrScA-S216-02", "OcnA-S116-01", "FrScA-S216-01"…
$ total_points_possible <dbl> 3280, 3531, 2870, 4562, 2207, 4208, 4325, 2086, …
$ total_points_earned   <dbl> 2220, 2672, 1897, 3090, 1910, 3596, 2255, 1719, …
$ percentage_earned     <dbl> 0.6768293, 0.7567261, 0.6609756, 0.6773345, 0.86…
$ subject               <chr> "FrScA", "OcnA", "FrScA", "OcnA", "PhysA", "FrSc…
$ semester              <chr> "S216", "S116", "S216", "S216", "S116", "S216", …
$ section               <chr> "02", "01", "01", "01", "01", "03", "01", "01", …
$ Gradebook_Item        <chr> "POINTS EARNED & TOTAL COURSE POINTS", "ATTEMPTE…
$ Grade_Category        <lgl> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, …
$ FinalGradeCEMS        <dbl> 93.45372, 81.70184, 88.48758, 81.85260, 84.00000…
$ Points_Possible       <dbl> 5, 10, 10, 5, 438, 5, 10, 10, 443, 5, 12, 10, 5,…
$ Points_Earned         <dbl> NA, 10.00, NA, 4.00, 399.00, NA, NA, 10.00, 425.…
$ Gender                <chr> "M", "F", "M", "M", "F", "F", "M", "F", "F", "M"…
$ q1                    <dbl> 5, 4, 5, 5, 4, NA, 5, 3, 4, NA, NA, 4, 3, 5, NA,…
$ q2                    <dbl> 4, 4, 4, 5, 3, NA, 5, 3, 3, NA, NA, 5, 3, 3, NA,…
$ q3                    <dbl> 4, 3, 4, 3, 3, NA, 3, 3, 3, NA, NA, 3, 3, 5, NA,…
$ q4                    <dbl> 5, 4, 5, 5, 4, NA, 5, 3, 4, NA, NA, 5, 3, 5, NA,…
$ q5                    <dbl> 5, 4, 5, 5, 4, NA, 5, 3, 4, NA, NA, 5, 4, 5, NA,…
$ q6                    <dbl> 5, 4, 4, 5, 4, NA, 5, 4, 3, NA, NA, 5, 3, 5, NA,…
$ q7                    <dbl> 5, 4, 4, 4, 4, NA, 4, 3, 3, NA, NA, 5, 3, 5, NA,…
$ q8                    <dbl> 5, 5, 5, 5, 4, NA, 5, 3, 4, NA, NA, 4, 3, 5, NA,…
$ q9                    <dbl> 4, 4, 3, 5, NA, NA, 5, 3, 2, NA, NA, 5, 2, 2, NA…
$ q10                   <dbl> 5, 4, 5, 5, 3, NA, 5, 3, 5, NA, NA, 4, 4, 5, NA,…
$ TimeSpent             <dbl> 1555.1667, 1382.7001, 860.4335, 1598.6166, 1481.…
$ TimeSpent_hours       <dbl> 25.91944500, 23.04500167, 14.34055833, 26.643610…
$ TimeSpent_std         <dbl> -0.18051496, -0.30780313, -0.69325954, -0.148446…
$ int                   <dbl> 5.0, 4.2, 5.0, 5.0, 3.8, 4.6, 5.0, 3.0, 4.2, NA,…
$ pc                    <dbl> 4.50, 3.50, 4.00, 3.50, 3.50, 4.00, 3.50, 3.00, …
$ uv                    <dbl> 4.333333, 4.000000, 3.666667, 5.000000, 3.500000…

Isolating Data with dplyr

We will use select() function to select the following columns from our data.

  • student_id

  • subject

  • semester

  • FinalGradeCEMS

  • After selecting these columns, assign that to a new object with a name of “student_grade”.

student_grade<-sci_online|>
  select(student_id, subject, semester, FinalGradeCEMS)

Your Turn:

Examine students’ grades, what did you realize about it?

Your response here: The grades are not in order numerically. There are numerous data points that are missing.

Hint: Check the missing data.

Specific select

Now, we will make a specific selection.

  • Select all columns except subject and semester.

  • Assign to a new object with a different name.

    examine your data frame.

sci_dataframe<-select(sci_online,-c(subject,semester))
sci_dataframe
# A tibble: 603 × 28
   student_id course_id     total_points_possible total_points_earned
        <dbl> <chr>                         <dbl>               <dbl>
 1      43146 FrScA-S216-02                  3280                2220
 2      44638 OcnA-S116-01                   3531                2672
 3      47448 FrScA-S216-01                  2870                1897
 4      47979 OcnA-S216-01                   4562                3090
 5      48797 PhysA-S116-01                  2207                1910
 6      51943 FrScA-S216-03                  4208                3596
 7      52326 AnPhA-S216-01                  4325                2255
 8      52446 PhysA-S116-01                  2086                1719
 9      53447 FrScA-S116-01                  4655                3149
10      53475 FrScA-S116-02                  1710                1402
# ℹ 593 more rows
# ℹ 24 more variables: percentage_earned <dbl>, section <chr>,
#   Gradebook_Item <chr>, Grade_Category <lgl>, FinalGradeCEMS <dbl>,
#   Points_Possible <dbl>, Points_Earned <dbl>, Gender <chr>, q1 <dbl>,
#   q2 <dbl>, q3 <dbl>, q4 <dbl>, q5 <dbl>, q6 <dbl>, q7 <dbl>, q8 <dbl>,
#   q9 <dbl>, q10 <dbl>, TimeSpent <dbl>, TimeSpent_hours <dbl>,
#   TimeSpent_std <dbl>, int <dbl>, pc <dbl>, uv <dbl>

Checking the data frame:

Your Turn:

  • Select all columns except student_id and FinalGradeCEMS.

  • Assign to a new object with a different name.

  • Examine your data frame.

sci_frame1<-select(sci_online,-c(student_id,FinalGradeCEMS))
sci_frame1
# A tibble: 603 × 28
   course_id total_points_possible total_points_earned percentage_earned subject
   <chr>                     <dbl>               <dbl>             <dbl> <chr>  
 1 FrScA-S2…                  3280                2220             0.677 FrScA  
 2 OcnA-S11…                  3531                2672             0.757 OcnA   
 3 FrScA-S2…                  2870                1897             0.661 FrScA  
 4 OcnA-S21…                  4562                3090             0.677 OcnA   
 5 PhysA-S1…                  2207                1910             0.865 PhysA  
 6 FrScA-S2…                  4208                3596             0.855 FrScA  
 7 AnPhA-S2…                  4325                2255             0.521 AnPhA  
 8 PhysA-S1…                  2086                1719             0.824 PhysA  
 9 FrScA-S1…                  4655                3149             0.676 FrScA  
10 FrScA-S1…                  1710                1402             0.820 FrScA  
# ℹ 593 more rows
# ℹ 23 more variables: semester <chr>, section <chr>, Gradebook_Item <chr>,
#   Grade_Category <lgl>, Points_Possible <dbl>, Points_Earned <dbl>,
#   Gender <chr>, q1 <dbl>, q2 <dbl>, q3 <dbl>, q4 <dbl>, q5 <dbl>, q6 <dbl>,
#   q7 <dbl>, q8 <dbl>, q9 <dbl>, q10 <dbl>, TimeSpent <dbl>,
#   TimeSpent_hours <dbl>, TimeSpent_std <dbl>, int <dbl>, pc <dbl>, uv <dbl>

Specific select

  • Select only the columns that start with Time

  • Assign to a new object with a different name.

  • Use view() function to examine your data frame.

time_object<-select(sci_online,starts_with("Time"))
view(time_object)

Your Turn:

  • Select only the columns that ends with “r”

  • Assign to a new object with a different name.

  • Use view() function to examine your data frame.

r_object<-select(sci_online,ends_with("r"))
view(r_object)

Filter Function

  • Filter the sci_classes data frame for just males.

  • Assign to a new object.

  • Use the head() function to examine your data frame.

male_student<-sci_online|>
  filter(Gender=="M")
head(male_student)
# A tibble: 6 × 30
  student_id course_id     total_points_possible total_points_earned
       <dbl> <chr>                         <dbl>               <dbl>
1      43146 FrScA-S216-02                  3280                2220
2      47448 FrScA-S216-01                  2870                1897
3      47979 OcnA-S216-01                   4562                3090
4      52326 AnPhA-S216-01                  4325                2255
5      53475 FrScA-S116-02                  1710                1402
6      53475 FrScA-S216-01                  1209                 977
# ℹ 26 more variables: percentage_earned <dbl>, subject <chr>, semester <chr>,
#   section <chr>, Gradebook_Item <chr>, Grade_Category <lgl>,
#   FinalGradeCEMS <dbl>, Points_Possible <dbl>, Points_Earned <dbl>,
#   Gender <chr>, q1 <dbl>, q2 <dbl>, q3 <dbl>, q4 <dbl>, q5 <dbl>, q6 <dbl>,
#   q7 <dbl>, q8 <dbl>, q9 <dbl>, q10 <dbl>, TimeSpent <dbl>,
#   TimeSpent_hours <dbl>, TimeSpent_std <dbl>, int <dbl>, pc <dbl>, uv <dbl>

Your Turn:

  • Filter the sci_classes data frame for just females.

  • Assign to a new object.

  • Use the tail() function to examine your data frame.

female_student<-sci_online|>
  filter(Gender=="F")
tail(female_student)
# A tibble: 6 × 30
  student_id course_id     total_points_possible total_points_earned
       <dbl> <chr>                         <dbl>               <dbl>
1      97150 PhysA-S216-01                  2710                1803
2      97265 PhysA-S216-01                  3101                2078
3      97272 OcnA-S216-01                   2872                1733
4      97374 BioA-S216-01                   8586                6978
5      97386 BioA-S216-01                   2761                1937
6      97441 FrScA-S216-02                  2607                2205
# ℹ 26 more variables: percentage_earned <dbl>, subject <chr>, semester <chr>,
#   section <chr>, Gradebook_Item <chr>, Grade_Category <lgl>,
#   FinalGradeCEMS <dbl>, Points_Possible <dbl>, Points_Earned <dbl>,
#   Gender <chr>, q1 <dbl>, q2 <dbl>, q3 <dbl>, q4 <dbl>, q5 <dbl>, q6 <dbl>,
#   q7 <dbl>, q8 <dbl>, q9 <dbl>, q10 <dbl>, TimeSpent <dbl>,
#   TimeSpent_hours <dbl>, TimeSpent_std <dbl>, int <dbl>, pc <dbl>, uv <dbl>

Let’s try filter function with two arguments now.

  • Filter the sci_classes data frame for students whose

  • percentage_earned is greater than 0.8

  • in the class “BioA”

  • Assign to a new object.

  • Use the tail() function to examine your data frame. 

bio_students<-filter(sci_online,percentage_earned>0.8&subject=="BioA")
tail(bio_students)
# A tibble: 6 × 30
  student_id course_id    total_points_possible total_points_earned
       <dbl> <chr>                        <dbl>               <dbl>
1      91066 BioA-S116-01                  5766                4820
2      91067 BioA-S116-01                  2672                2249
3      92633 BioA-S116-01                  2954                2495
4      95658 BioA-S216-01                  3362                2775
5      96950 BioA-S216-01                  6190                4970
6      97374 BioA-S216-01                  8586                6978
# ℹ 26 more variables: percentage_earned <dbl>, subject <chr>, semester <chr>,
#   section <chr>, Gradebook_Item <chr>, Grade_Category <lgl>,
#   FinalGradeCEMS <dbl>, Points_Possible <dbl>, Points_Earned <dbl>,
#   Gender <chr>, q1 <dbl>, q2 <dbl>, q3 <dbl>, q4 <dbl>, q5 <dbl>, q6 <dbl>,
#   q7 <dbl>, q8 <dbl>, q9 <dbl>, q10 <dbl>, TimeSpent <dbl>,
#   TimeSpent_hours <dbl>, TimeSpent_std <dbl>, int <dbl>, pc <dbl>, uv <dbl>

Your Turn:

Filter the sci_classes data frame for students whose

  • percentage_earned is smaller or equal to 0.6

  • Assign to a new object.

  • Use the head() function to examine your data frame. 

friends<-filter(sci_online,percentage_earned<=0.6&subject=="BioA")
head(friends)
# A tibble: 5 × 30
  student_id course_id    total_points_possible total_points_earned
       <dbl> <chr>                        <dbl>               <dbl>
1      84794 BioA-T116-01                  2787                1439
2      85889 BioA-S116-01                  3838                2248
3      86067 BioA-S116-01                  4054                2304
4      86216 BioA-S116-01                  2583                1452
5      95707 BioA-S216-01                  3912                2196
# ℹ 26 more variables: percentage_earned <dbl>, subject <chr>, semester <chr>,
#   section <chr>, Gradebook_Item <chr>, Grade_Category <lgl>,
#   FinalGradeCEMS <dbl>, Points_Possible <dbl>, Points_Earned <dbl>,
#   Gender <chr>, q1 <dbl>, q2 <dbl>, q3 <dbl>, q4 <dbl>, q5 <dbl>, q6 <dbl>,
#   q7 <dbl>, q8 <dbl>, q9 <dbl>, q10 <dbl>, TimeSpent <dbl>,
#   TimeSpent_hours <dbl>, TimeSpent_std <dbl>, int <dbl>, pc <dbl>, uv <dbl>

Let’s use filter () function for the missing data.

  • Filter the sci_classes data frame so rows with 

  • NA for points earned are removed.

  • Assign to a new object.

  • Use the glimpse() function to examine your data frame.

clean_data<-sci_online|>
  filter(!is.na(Points_Earned))
glimpse(clean_data)
Rows: 511
Columns: 30
$ student_id            <dbl> 44638, 47979, 48797, 52446, 53447, 53475, 53475,…
$ course_id             <chr> "OcnA-S116-01", "OcnA-S216-01", "PhysA-S116-01",…
$ total_points_possible <dbl> 3531, 4562, 2207, 2086, 4655, 1710, 1209, 4641, …
$ total_points_earned   <dbl> 2672, 3090, 1910, 1719, 3149, 1402, 977, 3429, 2…
$ percentage_earned     <dbl> 0.7567261, 0.6773345, 0.8654282, 0.8240652, 0.67…
$ subject               <chr> "OcnA", "OcnA", "PhysA", "PhysA", "FrScA", "FrSc…
$ semester              <chr> "S116", "S216", "S116", "S116", "S116", "S116", …
$ section               <chr> "01", "01", "01", "01", "01", "02", "01", "01", …
$ Gradebook_Item        <chr> "ATTEMPTED", "POINTS EARNED & TOTAL COURSE POINT…
$ Grade_Category        <lgl> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, …
$ FinalGradeCEMS        <dbl> 81.70184, 81.85260, 84.00000, 97.77778, 96.11872…
$ Points_Possible       <dbl> 10, 5, 438, 10, 443, 5, 12, 10, 5, 10, 220, 30, …
$ Points_Earned         <dbl> 10.00, 4.00, 399.00, 10.00, 425.00, 2.50, 12.00,…
$ Gender                <chr> "F", "M", "F", "F", "F", "M", "M", "M", "F", "F"…
$ q1                    <dbl> 4, 5, 4, 3, 4, NA, NA, 4, 3, 5, NA, 4, 4, NA, 4,…
$ q2                    <dbl> 4, 5, 3, 3, 3, NA, NA, 5, 3, 3, NA, 2, 4, NA, 3,…
$ q3                    <dbl> 3, 3, 3, 3, 3, NA, NA, 3, 3, 5, NA, 2, 3, NA, 3,…
$ q4                    <dbl> 4, 5, 4, 3, 4, NA, NA, 5, 3, 5, NA, 4, 5, NA, 4,…
$ q5                    <dbl> 4, 5, 4, 3, 4, NA, NA, 5, 4, 5, NA, 4, 4, NA, 4,…
$ q6                    <dbl> 4, 5, 4, 4, 3, NA, NA, 5, 3, 5, NA, 4, 4, NA, 3,…
$ q7                    <dbl> 4, 4, 4, 3, 3, NA, NA, 5, 3, 5, NA, 4, 5, NA, 3,…
$ q8                    <dbl> 5, 5, 4, 3, 4, NA, NA, 4, 3, 5, NA, 4, 4, NA, 4,…
$ q9                    <dbl> 4, 5, NA, 3, 2, NA, NA, 5, 2, 2, NA, 2, 4, NA, 2…
$ q10                   <dbl> 4, 5, 3, 3, 5, NA, NA, 4, 4, 5, NA, 4, 4, NA, 3,…
$ TimeSpent             <dbl> 1382.7001, 1598.6166, 1481.8000, 1390.2167, 1479…
$ TimeSpent_hours       <dbl> 23.04500167, 26.64361000, 24.69666667, 23.170278…
$ TimeSpent_std         <dbl> -0.30780313, -0.14844697, -0.23466291, -0.302255…
$ int                   <dbl> 4.2, 5.0, 3.8, 3.0, 4.2, NA, NA, 4.4, 3.4, 4.7, …
$ pc                    <dbl> 3.50, 3.50, 3.50, 3.00, 3.00, NA, NA, 4.00, 3.00…
$ uv                    <dbl> 4.000000, 5.000000, 3.500000, 3.333333, 2.666667…

Filter the sci_classes data for the following subjects:

  • BioA

  • PhysA

  • OcnA

  • Assign to a new object with a different name.

  • Use the summary() function to examine your data frame.

my_classes<-filter(sci_online,subject%in%c("BioA","PhysA","OcnA"))

Arrange () Function

Let’s recall how we were using the arrange () function for our dataset.

  • Arrange sci_classes by subject subject then 

  • percentage_earned in descending order.

  • Assign to a new object.

  • Use the str() function to examine your data frame.

order_classes<-sci_online|>
  arrange(subject, desc(percentage_earned))
str(order_classes)
spc_tbl_ [603 × 30] (S3: spec_tbl_df/tbl_df/tbl/data.frame)
 $ student_id           : num [1:603] 70192 86488 96690 91175 86267 ...
 $ course_id            : chr [1:603] "AnPhA-S116-02" "AnPhA-S116-01" "AnPhA-S216-01" "AnPhA-S116-02" ...
 $ total_points_possible: num [1:603] 1936 3342 4804 3199 3045 ...
 $ total_points_earned  : num [1:603] 1763 3033 4309 2867 2705 ...
 $ percentage_earned    : num [1:603] 0.911 0.908 0.897 0.896 0.888 ...
 $ subject              : chr [1:603] "AnPhA" "AnPhA" "AnPhA" "AnPhA" ...
 $ semester             : chr [1:603] "S116" "S116" "S216" "S116" ...
 $ section              : chr [1:603] "02" "01" "01" "02" ...
 $ Gradebook_Item       : chr [1:603] "POINTS EARNED & TOTAL COURSE POINTS" "POINTS EARNED & TOTAL COURSE POINTS" "POINTS EARNED & TOTAL COURSE POINTS" "POINTS EARNED & TOTAL COURSE POINTS" ...
 $ Grade_Category       : logi [1:603] NA NA NA NA NA NA ...
 $ FinalGradeCEMS       : num [1:603] 96 87.4 64.8 82.2 35.1 ...
 $ Points_Possible      : num [1:603] 10 28 10 5 50 15 10 10 353 460 ...
 $ Points_Earned        : num [1:603] 7 26 3 5 50 11 8 10 330 452 ...
 $ Gender               : chr [1:603] "F" "M" "F" "F" ...
 $ q1                   : num [1:603] 4 4 4 5 5 4 5 4 NA NA ...
 $ q2                   : num [1:603] 3 4 3 3 5 2 4 4 NA NA ...
 $ q3                   : num [1:603] 3 2 2 3 3 3 4 3 NA NA ...
 $ q4                   : num [1:603] 4 3 5 5 5 4 5 4 NA NA ...
 $ q5                   : num [1:603] 4 3 4 5 5 4 5 4 NA NA ...
 $ q6                   : num [1:603] 3 3 4 4 5 3 5 4 NA NA ...
 $ q7                   : num [1:603] 3 3 3 3 4 4 5 4 NA NA ...
 $ q8                   : num [1:603] 5 2 4 5 5 4 4 4 NA NA ...
 $ q9                   : num [1:603] 2 3 3 3 5 1 4 4 NA NA ...
 $ q10                  : num [1:603] 5 3 2 5 5 2 5 4 NA NA ...
 $ TimeSpent            : num [1:603] 1537 3600 1970 1315 406 ...
 $ TimeSpent_hours      : num [1:603] 25.62 60 32.83 21.92 6.77 ...
 $ TimeSpent_std        : num [1:603] -0.194 1.328 0.125 -0.358 -1.029 ...
 $ int                  : num [1:603] 4.4 3 3.8 5 5 3.9 4.6 4 4.8 4.6 ...
 $ pc                   : num [1:603] 3 2.5 2.5 3 3.5 3.5 3.75 3.5 3.5 4.5 ...
 $ uv                   : num [1:603] 2.67 3.33 3.33 3.33 5 ...
 - attr(*, "spec")=
  .. cols(
  ..   student_id = col_double(),
  ..   course_id = col_character(),
  ..   total_points_possible = col_double(),
  ..   total_points_earned = col_double(),
  ..   percentage_earned = col_double(),
  ..   subject = col_character(),
  ..   semester = col_character(),
  ..   section = col_character(),
  ..   Gradebook_Item = col_character(),
  ..   Grade_Category = col_logical(),
  ..   FinalGradeCEMS = col_double(),
  ..   Points_Possible = col_double(),
  ..   Points_Earned = col_double(),
  ..   Gender = col_character(),
  ..   q1 = col_double(),
  ..   q2 = col_double(),
  ..   q3 = col_double(),
  ..   q4 = col_double(),
  ..   q5 = col_double(),
  ..   q6 = col_double(),
  ..   q7 = col_double(),
  ..   q8 = col_double(),
  ..   q9 = col_double(),
  ..   q10 = col_double(),
  ..   TimeSpent = col_double(),
  ..   TimeSpent_hours = col_double(),
  ..   TimeSpent_std = col_double(),
  ..   int = col_double(),
  ..   pc = col_double(),
  ..   uv = col_double()
  .. )
 - attr(*, "problems")=<externalptr>

%>% Pipe Operator

Using sci_classes data and the %>% pipe operator:

  • Select subject, section, time spent in hours and final course grade.

  • Filter for students in OcnA courses with grades greater than or equal to 60.

  • Arrange grades by section in descending order.

  • Assign to a new object.

Examine the contents using a method of your choosing.

specific_course<-sci_online%>%
  select(subject,section,TimeSpent_hours,FinalGradeCEMS)%>%
  filter(subject=="OcnA"&FinalGradeCEMS>=60)%>%
  arrange(desc(section))

Deriving info with dplyr

We will practice summarise () and group_by () functions now.

Summarise () Function

Using sci_classes data and the summarise() function:

  • Get a distinct count of course ids.

  • Use the %>% operator

sci_online%>%
  summarise(course<-n_distinct(course_id))
# A tibble: 1 × 1
  `course <- n_distinct(course_id)`
                              <int>
1                                26

  • Get a distinct count of course ids.

  • Use the |> operator

sci_online|>
  summarise(course<-n_distinct(course_id))
# A tibble: 1 × 1
  `course <- n_distinct(course_id)`
                              <int>
1                                26

Group_by () Function

Using the sci_classes data and the pipe operator.

  • Filter final grades to remove NAs.

  • Group your data by subject and gender.

  • Summarise your data to calculate the following stats:

  • total number of students

  • mean final grade

  • mean time spent in the course

  • Assign to a new object

  • Examine the contents using a method of your choosing.

final<-sci_online%>%
  filter(!is.na(FinalGradeCEMS))%>%
  group_by(subject,Gender)%>%
  summarise(total=sum(student_id), 
            grade=mean(FinalGradeCEMS), 
            time=mean(TimeSpent_hours))
`summarise()` has grouped output by 'subject'. You can override using the
`.groups` argument.
head(final)
# A tibble: 6 × 5
# Groups:   subject [3]
  subject Gender    total grade  time
  <chr>   <chr>     <dbl> <dbl> <dbl>
1 AnPhA   F       7685263  74.3  40.3
2 AnPhA   M       4291668  76.4  43.5
3 BioA    F       2468063  66.5  23.3
4 BioA    M       1107520  62.2  18.5
5 FrScA   F      13794163  79.5  26.0
6 FrScA   M       5612344  83.3  29.5

Mutate () Function

Replace the dashed lines in the following code to;

  • Create a new variable called score that is the product of percentage earned and 100

  • Create a faceted scatter plot with hours spent in the course on the x-axis, score on the y-axis, and point colored by gender.

  • Include an alpha value to your graph.

sci_online %>%
  mutate(score=percentage_earned*100)%>%
  ggplot() +
  geom_point(mapping = aes(x =TimeSpent_hours,
                           y =score,
                           col=Gender)) +
  facet_wrap(~subject)

Final Step:

You are almost done, all you need to is to render your file and publish it in one of the following platform.

Your Turn:

Render File: For now, we will wrap up this work by converting our work into a webpage that can be used to communicate your learning and demonstrate some of your new R skills. To do so, you will need to “render” your document by clicking the Render button in the menu bar at that the top of this file. This will do two things; it will:

  1. check through all your code for any errors; and,

  2. create a file in your directory that you can use to share you work through Posit Cloud, RPubs , GitHub Pages, Quarto Pub, or other methods.

  3. Submit your link to the Blackboard!

Now that you’ve finished your Rtutorial study, scroll back to the very top of this Quarto Document and change the author: “YOUR NAME HERE” to your actual name surrounded by quotation marks like so: author: “Dr. Cansu Tatar”.