How Hockey Taught Me R

# How Hockey Taught Me R

Meghan Hall <br> <i class="fab  fa-twitter "></i> [@MeghanMHall](https://www.twitter.com/MeghanMHall) <br> <i class="fas  fa-link "></i> [meghan.rbind.io](https://meghan.rbind.io/) <br> R-Ladies Vancouver <br> Mar 25, 2021

---
background-image: url(figs/RLadies_VAN/RLad_VAN.png)
background-position: 98% 2%
background-size: 102px 115px
padding-right: 10px
layout: true
<div class="my-footer"><span>tinyurl.com/rladies-van</span></div>
---

# Housekeeping

🖥&nbsp; 
<br>[tinyurl.com/rladies-van](https://tinyurl.com/rladies-van)

<br>

📦&nbsp;

```r
devtools::install_github("meghall06/betweenthepipes")
```
<br>

⏰&nbsp;

<br>

❓&nbsp;

---

# The Land Before R

🎓&nbsp; 
<br>
the perils of Excel in a reporting-heavy office

<br>
--

🏒&nbsp;
<br>
the problem of "big" data and constantly having *more* data

---

# Why R?
--

🔓&nbsp; 
<br>
open source = free

<br>

<i class="fab  fa-twitter "></i>&nbsp; 
<br>
community through `#rstats` and `R-Ladies`

<br>

---

# Post-R

🎓&nbsp; 
<br>
*everything* is streamlined

<br>
--

🏒&nbsp;
<br>
more analysis, more opportunities, more helping!

---
class: inverse, middle, center

# What you're all here for

---

## Method endorsed by multiple professionals!

<br>
<br>
.center[<img src="figs/RLadies_VAN/tweet.png" width="585px" height="285px"/>]

---

# Where does the data come from?

```r
# install the package from github
devtools::install_github("meghall06/betweenthepipes")

# load the libraries
library(betweenthepipes)
*library(tidyverse)

# add the data from the package to the global environment
pbp <- pbp_example
```

--
*scrape for yourself using the [Evolving Hockey](https://evolving-hockey.com/) [R scraper](https://github.com/evolvingwild/evolving-hockey/blob/master/EH_scrape_functions.R)*

---

# Tonight's exercises

<br>
.center[team faceoff percentage]

<br>
.center[individual plus-minus]

---

# Goalie save percentage

What is this data? How do we find saves??

```r
pbp %>% 
  count(game_id, game_date, home_team, away_team)
```

---

# Goalie save percentage

What is this data? How do we find saves??

```r
pbp %>% 
  count(event_type)
```

<table class="table" style="font-size: 15px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> n </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> CHANGE </td>
   <td style="text-align:right;"> 1300 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:right;"> 237 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 211 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> STOP </td>
   <td style="text-align:right;"> 190 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> HIT </td>
   <td style="text-align:right;"> 134 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BLOCK </td>
   <td style="text-align:right;"> 118 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> GIVE </td>
   <td style="text-align:right;"> 101 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> MISS </td>
   <td style="text-align:right;"> 71 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> TAKE </td>
   <td style="text-align:right;"> 44 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PENL </td>
   <td style="text-align:right;"> 25 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:right;"> 21 </td>
  </tr>
</tbody>
</table>

---

# Goalie save percentage

What is this data? How do we find saves??

```r
pbp %>% 
  count(event_type)
```

<table class="table" style="font-size: 15px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> n </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> CHANGE </td>
   <td style="text-align:right;"> 1300 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:right;"> 237 </td>
  </tr>
  <tr>
   <td style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> SHOT </td>
   <td style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> 211 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> STOP </td>
   <td style="text-align:right;"> 190 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> HIT </td>
   <td style="text-align:right;"> 134 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BLOCK </td>
   <td style="text-align:right;"> 118 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> GIVE </td>
   <td style="text-align:right;"> 101 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> MISS </td>
   <td style="text-align:right;"> 71 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> TAKE </td>
   <td style="text-align:right;"> 44 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PENL </td>
   <td style="text-align:right;"> 25 </td>
  </tr>
  <tr>
   <td style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> GOAL </td>
   <td style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> 21 </td>
  </tr>
</tbody>
</table>

---

# Goalie save percentage

`save percentage = SHOTs / (SHOTs + GOALs)`
--

```r
pbp %>% 
  filter(event_type `%in%` c("SHOT","GOAL")) %>% 
  select(event_type, `contains("goalie")`, 
         event_team, event_description)
```

<table class="table" style="font-size: 14px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_description </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR #20 AHO(11), Wrist, Off. Zone, 16 ft.Assists: #86 TERAVAINEN(15); #22 PESCE(6) </td>
  </tr>
  <tr>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR #86 TERAVAINEN(6), Snap, Off. Zone, 32 ft.Assists: #37 SVECHNIKOV(14); #18 DZINGEL(11) </td>
  </tr>
  <tr>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR ONGOAL - #13 FOEGELE, Wrist, Off. Zone, 6 ft. </td>
  </tr>
  <tr>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR ONGOAL - #13 FOEGELE, Wrist, Off. Zone, 5 ft. </td>
  </tr>
  <tr>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR ONGOAL - #13 FOEGELE, Deflected, Off. Zone, 4 ft. </td>
  </tr>
</tbody>
</table>

---

# Goalie save percentage

<br>
--
.large[what structure does my data **need** to be in?]
<br>
<br>
    *the actual event goalie specified on the row*
    
<br>
--
.large[how do I get from point A to point B?]
<br>
<br>
    *create a new variable*
    
---

# Goalie save percentage

```r
pbp %>% 
  filter(event_type %in% c("GOAL","SHOT")) %>% 
  mutate(event_goalie = `case_when`(
                          event_team == home_team ~ away_goalie,
                          event_team == away_team ~ home_goalie)) %>% 
  select(event_goalie, event_type)
```

<table class="table" style="font-size: 15px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> GOAL </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> GOAL </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> SHOT </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> GOAL </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
  </tr>
</tbody>
</table>

---

# Goalie save percentage

<table class="table" style="font-size: 15px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> save </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:right;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:right;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:right;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
</tbody>
</table>

---

# Goalie save percentage

```r
pbp %>% 
  filter(event_type %in% c("GOAL","SHOT")) %>% 
  mutate(event_goalie = case_when(
                          event_team == home_team ~ away_goalie,
                          event_team == away_team ~ home_goalie),
         save = ifelse(event_type == "SHOT", 1, 0)) %>% 
  select(event_goalie, event_type, save) %>% 
  `group_by`(event_goalie) %>% 
  `summarize`(saves = sum(save),
              all_shots = n()) %>% 
  `arrange`(desc(all_shots))
```

---

# Goalie save percentage

```r
pbp %>% 
  filter(event_type %in% c("GOAL","SHOT")) %>% 
  mutate(event_goalie = case_when(
                          event_team == home_team ~ away_goalie,
                          event_team == away_team ~ home_goalie),
         save = ifelse(event_type == "SHOT", 1, 0)) %>% 
  select(event_goalie, event_type, save) %>% 
  group_by(event_goalie) %>% 
  summarize(saves = sum(save),
              all_shots = n()) %>% 
  arrange(desc(all_shots)) %>% 
  `mutate(save_perc = saves / all_shots)`
```

<table class="table" style="font-size: 15px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_goalie </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> saves </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> all_shots </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> save_perc </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:right;"> 61 </td>
   <td style="text-align:right;"> 66 </td>
   <td style="text-align:right;"> 0.9242424 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:right;"> 42 </td>
   <td style="text-align:right;"> 46 </td>
   <td style="text-align:right;"> 0.9130435 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> DAVID.RITTICH </td>
   <td style="text-align:right;"> 39 </td>
   <td style="text-align:right;"> 41 </td>
   <td style="text-align:right;"> 0.9512195 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> THATCHER.DEMKO </td>
   <td style="text-align:right;"> 32 </td>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:right;"> 0.9411765 </td>
  </tr>
</tbody>
</table>

---

# Tonight's exercises

<br>
.center[.large[**team faceoff percentage**]]

<br>
.center[individual plus-minus]

---

# Team faceoff percentage

```r
pbp %>% 
  count(event_type)
```

<table class="table" style="font-size: 16px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> n </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> CHANGE </td>
   <td style="text-align:right;"> 1300 </td>
  </tr>
  <tr>
   <td style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> FAC </td>
   <td style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> 237 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> SHOT </td>
   <td style="text-align:right;"> 211 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> STOP </td>
   <td style="text-align:right;"> 190 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> HIT </td>
   <td style="text-align:right;"> 134 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> BLOCK </td>
   <td style="text-align:right;"> 118 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> GIVE </td>
   <td style="text-align:right;"> 101 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> MISS </td>
   <td style="text-align:right;"> 71 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> TAKE </td>
   <td style="text-align:right;"> 44 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> PENL </td>
   <td style="text-align:right;"> 25 </td>
  </tr>
</tbody>
</table>

---

# Team faceoff percentage

```r
pbp %>% 
  filter(event_type == "FAC") %>% 
  select(event_index, event_type, event_player_1, event_player_2, 
         event_team, event_description)
```

<table class="table" style="font-size: 14px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_player_1 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_player_2 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_description </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 7 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
   <td style="text-align:left;"> SEBASTIAN.AHO </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI won Neu. Zone - PHI #28 GIROUX vs CAR #20 AHO </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 14 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> SEAN.COUTURIER </td>
   <td style="text-align:left;"> JORDAN.STAAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI won Neu. Zone - PHI #14 COUTURIER vs CAR #11 STAAL </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 23 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> KEVIN.HAYES </td>
   <td style="text-align:left;"> LUCAS.WALLMARK </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI won Def. Zone - PHI #13 HAYES vs CAR #71 WALLMARK </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 37 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> SEAN.COUTURIER </td>
   <td style="text-align:left;"> RYAN.DZINGEL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI won Neu. Zone - PHI #14 COUTURIER vs CAR #18 DZINGEL </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 41 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
   <td style="text-align:left;"> RYAN.DZINGEL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI won Def. Zone - PHI #28 GIROUX vs CAR #18 DZINGEL </td>
  </tr>
</tbody>
</table>

---

# Team faceoff percentage

<table class="table" style="font-size: 14px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> winner </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> loser </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 7 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 14 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 23 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 37 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 41 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 50 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 60 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 66 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 71 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 75 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
</tbody>
</table>

---

# Team faceoff percentage

.large[what structure is my data in?]
<br>
<br>
    *one row per faceoff—which is actually two data points (the winner and the loser)*

<br>
--
.large[what structure does my data **need** to be in?]
<br>
<br>
    *one row per each **team** in the faceoff (one row per data point!)*
    
<br>
--
.large[how do I get from point A to point B?]
<br>
<br>
    *pivot!*
    
---

# Team Faceoff Percentage

.center[<img src="figs/RLadies_VAN/pivot.png" width="574px" height="236px"/>]
.center[*[from R for Data Science](https://r4ds.had.co.nz/)*]

---

# Team faceoff percentage

<table class="table" style="font-size: 13px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> result </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> team </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 7 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> winner </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 7 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> loser </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 14 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> winner </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 14 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> loser </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 23 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> winner </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 23 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> loser </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 37 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> winner </td>
   <td style="text-align:left;"> PHI </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 37 </td>
   <td style="text-align:left;"> FAC </td>
   <td style="text-align:left;"> loser </td>
   <td style="text-align:left;"> CAR </td>
  </tr>
</tbody>
</table>

---

# Team faceoff percentage

```r
pbp %>% 
  filter(event_type == "FAC") %>% 
  mutate(loser = case_when(event_team == home_team ~ away_team,
                           event_team == away_team ~ home_team)) %>% 
  select(event_index, event_type, winner = event_team, loser) %>% 
  pivot_longer(winner:loser,
                names_to = "result", values_to = "team") %>% 
* mutate(win = ifelse(result == "winner", 1, 0)) %>%
* group_by(team) %>%
* summarize(wins = sum(win),
*           faceoffs = n()) %>%
* mutate(fo_perc = wins / faceoffs)
```

<table class="table" style="font-size: 13px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> team </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> wins </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> faceoffs </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> fo_perc </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:right;"> 135 </td>
   <td style="text-align:right;"> 237 </td>
   <td style="text-align:right;"> 0.5696203 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:right;"> 30 </td>
   <td style="text-align:right;"> 74 </td>
   <td style="text-align:right;"> 0.4054054 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:right;"> 27 </td>
   <td style="text-align:right;"> 59 </td>
   <td style="text-align:right;"> 0.4576271 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> CBJ </td>
   <td style="text-align:right;"> 25 </td>
   <td style="text-align:right;"> 52 </td>
   <td style="text-align:right;"> 0.4807692 </td>
  </tr>
</tbody>
</table>

---

# Tonight's exercises

<br>
.center[team faceoff percentage]

<br>
.center[.large[**individual plus-minus**]]

---

# Individual plus-minus

---

# Individual plus-minus

<table class="table" style="font-size: 12px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_on_1 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_on_2 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_on_1 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_on_2 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> ANDREI.SVECHNIKOV </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 430 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:left;"> BROCK.MCGINN </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 503 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> ANDREI.SVECHNIKOV </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 364 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> JAKUB.VORACEK </td>
   <td style="text-align:left;"> BRANDON.DAVIDSON </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 433 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
   <td style="text-align:left;"> ANDREW.MANGIAPANE </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 587 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> JOEL.FARABEE </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
   <td style="text-align:left;"> DEREK.RYAN </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 123 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> VAN </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> VAN </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> JAMES.VAN RIEMSDYK </td>
   <td style="text-align:left;"> BO.HORVAT </td>
   <td style="text-align:left;"> J.T..MILLER </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 257 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> VAN </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> JAKUB.VORACEK </td>
   <td style="text-align:left;"> ALEX.EDLER </td>
   <td style="text-align:left;"> BO.HORVAT </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 509 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> VAN </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> JAKUB.VORACEK </td>
   <td style="text-align:left;"> CHRIS.TANEV </td>
   <td style="text-align:left;"> ELIAS.PETTERSSON </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 60 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CBJ </td>
   <td style="text-align:left;"> CBJ </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> DEAN.KUKAN </td>
   <td style="text-align:left;"> EMIL.BEMSTROM </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
</tbody>
</table>

---

# Team faceoff percentage

.large[what structure is my data in?]
<br>
<br>
    *one row per goal—which contains **many** data points*

<br>
--
.large[what structure does my data **need** to be in?]
<br>
<br>
    *one row per each player on the ice*
    
<br>
--
.large[how do I get from point A to point B?]
<br>
<br>
    *pivot again, with a twist*
    
---

# Individual plus-minus

<table class="table" style="font-size: 12px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_1 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_2 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_1 </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> away_2 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> ANDREI.SVECHNIKOV </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 430 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:left;"> BROCK.MCGINN </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 503 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> ANDREI.SVECHNIKOV </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:left;"> BRIAN.ELLIOTT </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 364 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> JAKUB.VORACEK </td>
   <td style="text-align:left;"> BRANDON.DAVIDSON </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 433 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> PHI </td>
   <td style="text-align:left;"> CGY </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
   <td style="text-align:left;"> CARTER.HART </td>
   <td style="text-align:left;"> CLAUDE.GIROUX </td>
   <td style="text-align:left;"> ANDREW.MANGIAPANE </td>
   <td style="text-align:left;"> DAVID.RITTICH </td>
  </tr>
</tbody>
</table>
    
---

# Individual plus-minus

---

# Individual plus-minus

<table class="table" style="font-size: 13px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_away </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> player </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> ANDREI.SVECHNIKOV </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> JOEL.EDMUNDSON </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> SEBASTIAN.AHO </td>
  </tr>
</tbody>
</table>

---

# Individual plus-minus

```r
pbp %>% 
  filter(game_strength_state == "5v5" & event_type == "GOAL") %>% 
  select(event_index, event_type, event_team, home_team, 
         away_team, home_goalie, away_goalie, contains("_on_")) %>% 
  rename_at(vars(contains("_on_")), ~str_replace(., "on_", "")) %>%
  pivot_longer(-c(starts_with("event")),
        names_to = c("home_away", ".value"), names_sep = "_") %>% 
  pivot_longer(`1`:`7`, names_to = NULL, values_to = "player",
               values_drop_na = TRUE) %>% 
* filter(player != goalie) %>%
* mutate(plus_minus = ifelse(event_team == team, 1, -1))
```

<table class="table" style="font-size: 13px; width: auto !important; margin-left: auto; margin-right: auto;">
 <thead>
  <tr>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_index </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_type </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> event_team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> home_away </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> team </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> goalie </th>
   <th style="text-align:left;font-weight: bold;color: white !important;background-color: #5C164E !important;"> player </th>
   <th style="text-align:right;font-weight: bold;color: white !important;background-color: #5C164E !important;"> plus_minus </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> ANDREI.SVECHNIKOV </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> BRETT.PESCE </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> JOEL.EDMUNDSON </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> SEBASTIAN.AHO </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
  <tr>
   <td style="text-align:right;"> 34 </td>
   <td style="text-align:left;"> GOAL </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> home </td>
   <td style="text-align:left;"> CAR </td>
   <td style="text-align:left;"> PETR.MRAZEK </td>
   <td style="text-align:left;"> TEUVO.TERAVAINEN </td>
   <td style="text-align:right;"> 1 </td>
  </tr>
</tbody>
</table>

---

# Individual plus-minus

```r
pbp %>% 
  filter(game_strength_state == "5v5" & event_type == "GOAL") %>% 
  select(event_index, event_type, event_team, home_team, 
         away_team, home_goalie, away_goalie, contains("_on_")) %>% 
  rename_at(vars(contains("_on_")), ~str_replace(., "on_", "")) %>% 
  pivot_longer(-c(starts_with("event")), 
        names_to = c("home_away", ".value"), names_sep = "_") %>% 
  pivot_longer(`1`:`7`, names_to = NULL, values_to = "player", 
               values_drop_na = TRUE) %>% 
  filter(player != goalie) %>% 
  mutate(plus_minus = ifelse(event_team == team, 1, -1)) %>% 
* group_by(player, team) %>%
* summarize(plus_minus = sum(plus_minus)) %>%
* arrange(desc(abs(plus_minus)))
```

---

# Even more exercises

<br>

<br>

*all code available [here](https://github.com/meghall06/personal-website/blob/master/static/RLadies_VAN_code.R)*

---

# Tiny tips for success

<br>
--
.large[use data you find interesting]
<br>
<br>
    *[Data is Plural](https://www.data-is-plural.com/) is a weekly newsletter with interesting datasets*<br>
    *[nflfastr](https://github.com/mrcaseb/nflfastR), [baseballr](http://billpetti.github.io/baseballr/)*
    
<br>
--
.large[focus first on the problems you have]
<br>
<br>
    *RMarkdown templates, ggplot themes, internal packages*

---

# Thank you!

Slides created via the R package [xaringan](https://github.com/yihui/xaringan).
<br>
<i class="fab  fa-twitter "></i> [@MeghanMHall](https://www.twitter.com/MeghanMHall)