26  Tables

But not a table. A table with features.

Sometimes, the best way to show your data is with a table – simple rows and columns. It allows a reader to compare whatever they want to compare a little easier than a graph where you’ve chosen what to highlight. The folks that made R Studio and the tidyverse have a neat package called gt.

For this assignment, we’ll need gt so go over to the console and run:

install.packages("gt")

So what does all of these libraries do? Let’s gather a few and use data of every game in the last 5 years.

For this walkthrough:

Load libraries.

library(tidyverse)
library(gt)

And the data.

logs <- read_csv("data/logs1520.csv")
Rows: 68617 Columns: 44
── Column specification ────────────────────────────────────────────────────────
Delimiter: ","
chr   (6): HomeAway, Opponent, W_L, Team, Conference, season
dbl  (36): X1, Game, TeamScore, OpponentScore, TeamFG, TeamFGA, TeamFGPCT, T...
lgl   (1): Blank
date  (1): Date

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.

Let’s ask this question: Fred Ball is supposed to be play fast and shoot threes – a pro-style offense. How much did Nebraska change in that regard from Tim Miles? In other words, which college basketball team saw the greatest increase in three point attempts last season as a percentage of shots? The simplest way to calculate that is by percent change.

We’ve got a little work to do, putting together ideas we’ve used before. What we need to end up with is some data that looks like this:

Team | 2018-2019 season threes | 2019-2020 season threes | pct change

To get that, we’ll need to do some filtering to get the right seasons, some grouping and summarizing to get the right number, some pivoting to get it organized correctly so we can mutate the percent change.

threechange <- logs |>
  filter(season == "2018-2019" | season == "2019-2020") |>
  group_by(Team, Conference, season) |>
  summarise(Total3PA = sum(Team3PA)) |>
  pivot_wider(names_from=season, values_from = Total3PA) |>
  mutate(PercentChange = (`2019-2020`-`2018-2019`)/`2018-2019`) |>
  arrange(desc(PercentChange)) |> 
  ungroup() |>
  top_n(10) # just want a top 10 list
`summarise()` has grouped output by 'Team', 'Conference'. You can override
using the `.groups` argument.
Selecting by PercentChange

We’ve output tables to the screen a thousand times in this class with head, but gt makes them look decent with very little code.

threechange |> gt()
Team Conference 2018-2019 2019-2020 PercentChange
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037

So there you have it. Mississippi Valley State changed their team so much they took 51 percent more threes last season from the season before. Where did Nebraska come out? Isn’t Fred Ball supposed to be a lot of threes? We ranked 111th in college basketball in terms of change from the season before. Believe it or not, Nebraska took four fewer threes in the first season of Fred Ball than the last season of Tim Miles.

gt has a mountain of customization options. The good news is that it works in a very familiar pattern. We’ll start with fixing headers. What we have isn’t bad, but PercentChange isn’t good either. Let’s fix that.

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  )
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037

Better. Note the pattern: Actual header name = “What we want to see”. So if we wanted to change Team to School, we’d do this: Team = "School" inside the cols_label bits.

Now we can start working with styling. The truth is most of your code in tables is going to be dedicated to styling specific things. The first thing we need: A headline and some chatter. They’re required parts of a graphic, so they’re a good place to start. We do that with tab_header

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037

We have a headline and some chatter, but … gross. Centered? The extra lines? No real difference in font weight? We can do better. We can style individual elements using tab_style. First, let’s make the main headline – the title – bold and left aligned.

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |> tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037

It’s hard to see here, but the chatter below is also centered (it doesn’t look like it because it fills the space). We can left align that too, but leave it normal weight (i.e. not bold).

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |> tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  ) |> tab_style(
    style = cell_text(color = "black", align = "left"),
    locations = cells_title("subtitle")
  )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037

The next item on the required elements list: Source and credit lines. In gt, those are called tab_source_notes and we can add them like this:

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |> tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  ) |> tab_style(
    style = cell_text(color = "black", align = "left"),
    locations = cells_title("subtitle")
  ) |>
  tab_source_note(
    source_note = md("**By:** Matt Waite  |  **Source:** [Sports Reference](https://www.sports-reference.com/cbb/seasons/)")
  )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037
By: Matt Waite | Source: Sports Reference

We can do a lot with tab_style. For instance, we can make the headers bold and reduce the size a bit to reduce font congestion in the area.

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |> 
  tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  ) |> 
  tab_style(
    style = cell_text(color = "black", align = "left"),
    locations = cells_title("subtitle")
  ) |>  
  tab_source_note(
    source_note = md("**By:** Matt Waite  |  **Source:** [Sports Reference](https://www.sports-reference.com/cbb/seasons/)")
  ) |>
  tab_style(
     locations = cells_column_labels(columns = everything()),
     style = list(
       cell_borders(sides = "bottom", weight = px(3)),
       cell_text(weight = "bold", size=12)
     )
   )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037
By: Matt Waite | Source: Sports Reference

Next up: There’s a lot of lines in this that don’t need to be there. gt has some tools to get rid of them easily and add in some other readability improvements.

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |>  
  tab_source_note(
    source_note = md("**By:** Matt Waite  |  **Source:** [Sports Reference](https://www.sports-reference.com/cbb/seasons/)")
  ) |> 
  tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  ) |> 
  tab_style(
    style = cell_text(color = "black", align = "left"),
    locations = cells_title("subtitle")
  ) |>
  tab_style(
     locations = cells_column_labels(columns = everything()),
     style = list(
       cell_borders(sides = "bottom", weight = px(3)),
       cell_text(weight = "bold", size=12)
     )
   ) |>
  opt_row_striping() |> 
  opt_table_lines("none")
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 0.5108303
Valparaiso Crusaders MVC 585 843 0.4410256
Ball State Cardinals MAC 621 842 0.3558776
San Jose State Spartans MWC 641 861 0.3432137
Alabama Crimson Tide SEC 718 957 0.3328691
Minnesota Golden Gophers Big Ten 603 762 0.2636816
Georgia Southern Eagles Sun Belt 631 792 0.2551506
Tennessee Tech Golden Eagles OVC 620 776 0.2516129
San Francisco Dons WCC 728 899 0.2348901
McNeese State Cowboys Southland 547 675 0.2340037
By: Matt Waite | Source: Sports Reference

We’re in pretty good shape here, but look closer. What else makes this table sub-par? How about the formatting of the percent change? We can fix that with a formatter.

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |>  
  tab_source_note(
    source_note = md("**By:** Matt Waite  |  **Source:** [Sports Reference](https://www.sports-reference.com/cbb/seasons/)")
  ) |> 
  tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  ) |> 
  tab_style(
    style = cell_text(color = "black", align = "left"),
    locations = cells_title("subtitle")
  ) |>
  tab_style(
     locations = cells_column_labels(columns = everything()),
     style = list(
       cell_borders(sides = "bottom", weight = px(3)),
       cell_text(weight = "bold", size=12)
     )
   ) |>
  opt_row_striping() |> 
  opt_table_lines("none") |>
    fmt_percent(
    columns = c(PercentChange),
    decimals = 1
  )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 51.1%
Valparaiso Crusaders MVC 585 843 44.1%
Ball State Cardinals MAC 621 842 35.6%
San Jose State Spartans MWC 641 861 34.3%
Alabama Crimson Tide SEC 718 957 33.3%
Minnesota Golden Gophers Big Ten 603 762 26.4%
Georgia Southern Eagles Sun Belt 631 792 25.5%
Tennessee Tech Golden Eagles OVC 620 776 25.2%
San Francisco Dons WCC 728 899 23.5%
McNeese State Cowboys Southland 547 675 23.4%
By: Matt Waite | Source: Sports Reference

Throughout the semester, we’ve been using color and other signals to highlight things. Let’s pretend we’re doing a project on Minnesota. Note they’re the only Big Ten team on this list. With a little tab_style magic, we can change individual rows and add color. The last tab_style block here will first pass off the styles we want to use – we’re going to make the rows maroon and the text gold – and then for locations we specify where with a simple filter. What that means is that any rows we can address with logic – all rows with a value greater than X, for example – we can change the styling.

threechange |> 
  gt() |> 
  cols_label(
    PercentChange = "Percent Change"
  ) |>
  tab_header(
    title = "Does Hoiberg's offense push threes more than Miles?",
    subtitle = "Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense."
  ) |>  
  tab_source_note(
    source_note = md("**By:** Matt Waite  |  **Source:** [Sports Reference](https://www.sports-reference.com/cbb/seasons/)")
  ) |> 
  tab_style(
    style = cell_text(color = "black", weight = "bold", align = "left"),
    locations = cells_title("title")
  ) |> 
  tab_style(
    style = cell_text(color = "black", align = "left"),
    locations = cells_title("subtitle")
  ) |>
  tab_style(
     locations = cells_column_labels(columns = everything()),
     style = list(
       cell_borders(sides = "bottom", weight = px(3)),
       cell_text(weight = "bold", size=12)
     )
   ) |>
  opt_row_striping() |> 
  opt_table_lines("none") |>
    fmt_percent(
    columns = c(PercentChange),
    decimals = 1
  ) |>
  tab_style(
    style = list(
      cell_fill(color = "maroon"),
      cell_text(color = "gold")
      ),
    locations = cells_body(
      rows = Team == "Minnesota Golden Gophers")
  )
Does Hoiberg's offense push threes more than Miles?
Nebraska wasn't in the top 100 of teams shooting more threes. These 10 teams completely changed their offense.
Team Conference 2018-2019 2019-2020 Percent Change
Mississippi Valley State Delta Devils SWAC 554 837 51.1%
Valparaiso Crusaders MVC 585 843 44.1%
Ball State Cardinals MAC 621 842 35.6%
San Jose State Spartans MWC 641 861 34.3%
Alabama Crimson Tide SEC 718 957 33.3%
Minnesota Golden Gophers Big Ten 603 762 26.4%
Georgia Southern Eagles Sun Belt 631 792 25.5%
Tennessee Tech Golden Eagles OVC 620 776 25.2%
San Francisco Dons WCC 728 899 23.5%
McNeese State Cowboys Southland 547 675 23.4%
By: Matt Waite | Source: Sports Reference

Two things here:

  1. Dear God that color scheme is awful, which is fitting for a school that worships a lawn-wrecking varmint.
  2. We’ve arrived where we want to be: We’ve created a clear table that allows a reader to compare schools at will while also using color to draw attention to the thing we want to draw attention to. We’ve kept it simple so the color has impact.