As we get closer to the end of the baseball season, the San Francisco Giants and Los Angeles Dodgers both have over 100 wins. A friend asked if there had been situations where two 100 win teams had been in the same division AND there had been no other 100 win teams in other divisions. It’s kind of a weird question, but it inspired me to look at the Lahman database to find an answer.
library(Lahman)
library(tidyverse)## ── Attaching packages ─────────────────────────────────────── tidyverse 1.3.1 ──## ✓ ggplot2 3.3.5 ✓ purrr 0.3.4
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## x dplyr::filter() masks stats::filter()
## x dplyr::lag() masks stats::lag()The Lahman database contains a table called Teams that reports on the various team statistics for every baseball season from 1871 to the present day.
data(Teams)
str(Teams)## 'data.frame': 2955 obs. of 48 variables:
## $ yearID : int 1871 1871 1871 1871 1871 1871 1871 1871 1871 1872 ...
## $ lgID : Factor w/ 7 levels "AA","AL","FL",..: 4 4 4 4 4 4 4 4 4 4 ...
## $ teamID : Factor w/ 149 levels "ALT","ANA","ARI",..: 24 31 39 56 90 97 111 136 142 8 ...
## $ franchID : Factor w/ 120 levels "ALT","ANA","ARI",..: 13 36 25 56 70 85 91 109 77 9 ...
## $ divID : chr NA NA NA NA ...
## $ Rank : int 3 2 8 7 5 1 9 6 4 2 ...
## $ G : int 31 28 29 19 33 28 25 29 32 58 ...
## $ Ghome : int NA NA NA NA NA NA NA NA NA NA ...
## $ W : int 20 19 10 7 16 21 4 13 15 35 ...
## $ L : int 10 9 19 12 17 7 21 15 15 19 ...
## $ DivWin : chr NA NA NA NA ...
## $ WCWin : chr NA NA NA NA ...
## $ LgWin : chr "N" "N" "N" "N" ...
## $ WSWin : chr NA NA NA NA ...
## $ R : int 401 302 249 137 302 376 231 351 310 617 ...
## $ AB : int 1372 1196 1186 746 1404 1281 1036 1248 1353 2571 ...
## $ H : int 426 323 328 178 403 410 274 384 375 753 ...
## $ X2B : int 70 52 35 19 43 66 44 51 54 106 ...
## $ X3B : int 37 21 40 8 21 27 25 34 26 31 ...
## $ HR : int 3 10 7 2 1 9 3 6 6 14 ...
## $ BB : int 60 60 26 33 33 46 38 49 48 29 ...
## $ SO : int 19 22 25 9 15 23 30 19 13 28 ...
## $ SB : int 73 69 18 16 46 56 53 62 48 53 ...
## $ CS : int 16 21 8 4 15 12 10 24 13 18 ...
## $ HBP : int NA NA NA NA NA NA NA NA NA NA ...
## $ SF : int NA NA NA NA NA NA NA NA NA NA ...
## $ RA : int 303 241 341 243 313 266 287 362 303 434 ...
## $ ER : int 109 77 116 97 121 137 108 153 137 166 ...
## $ ERA : num 3.55 2.76 4.11 5.17 3.72 4.95 4.3 5.51 4.37 2.9 ...
## $ CG : int 22 25 23 19 32 27 23 28 32 48 ...
## $ SHO : int 1 0 0 1 1 0 1 0 0 1 ...
## $ SV : int 3 1 0 0 0 0 0 0 0 1 ...
## $ IPouts : int 828 753 762 507 879 747 678 750 846 1548 ...
## $ HA : int 367 308 346 261 373 329 315 431 371 573 ...
## $ HRA : int 2 6 13 5 7 3 3 4 4 3 ...
## $ BBA : int 42 28 53 21 42 53 34 75 45 63 ...
## $ SOA : int 23 22 34 17 22 16 16 12 13 77 ...
## $ E : int 243 229 234 163 235 194 220 198 218 432 ...
## $ DP : int 24 16 15 8 14 13 14 22 20 22 ...
## $ FP : num 0.834 0.829 0.818 0.803 0.84 0.845 0.821 0.845 0.85 0.83 ...
## $ name : chr "Boston Red Stockings" "Chicago White Stockings" "Cleveland Forest Citys" "Fort Wayne Kekiongas" ...
## $ park : chr "South End Grounds I" "Union Base-Ball Grounds" "National Association Grounds" "Hamilton Field" ...
## $ attendance : int NA NA NA NA NA NA NA NA NA NA ...
## $ BPF : int 103 104 96 101 90 102 97 101 94 106 ...
## $ PPF : int 98 102 100 107 88 98 99 100 98 102 ...
## $ teamIDBR : chr "BOS" "CHI" "CLE" "KEK" ...
## $ teamIDlahman45: chr "BS1" "CH1" "CL1" "FW1" ...
## $ teamIDretro : chr "BS1" "CH1" "CL1" "FW1" ...All I needed was the year, league, team, division, and wins. I also selected the games played and losses for completeness.
teams <- Teams %>% select(yearID, lgID, teamID, divID, Rank, G, W, L, name)
table(teams$divID, teams$lgID, useNA = "if")##
## AA AL FL NA NL PL UA
## C 0 135 0 0 150 0 0
## E 0 302 0 0 286 0 0
## W 0 283 0 0 282 0 0
## <NA> 85 560 16 50 786 8 12I filtered by 100 win teams then grouped these by year, league, and division. I counted the teams in each division that had won 100 games. Then I filtered by the years where there were more than 1 team in a division that had won at least 100 games.
teams %>% filter(W >= 100) %>%
group_by(yearID, lgID, divID) %>%
summarize(n_100_win_teams = n()) %>%
filter(n_100_win_teams > 1)## `summarise()` has grouped output by 'yearID', 'lgID'. You can override using the `.groups` argument.## # A tibble: 10 × 4
## # Groups: yearID, lgID [10]
## yearID lgID divID n_100_win_teams
## <int> <fct> <chr> <int>
## 1 1909 NL <NA> 2
## 2 1915 AL <NA> 2
## 3 1942 NL <NA> 2
## 4 1954 AL <NA> 2
## 5 1961 AL <NA> 2
## 6 1962 NL <NA> 2
## 7 1980 AL E 2
## 8 1993 NL W 2
## 9 2001 AL W 2
## 10 2018 AL E 2In 2018 the AL East had two 100 team winners, the Red Sox and Yankees (108 and 100 wins respectively). However there was actually another team that had 100 wins, the Houston Astros, so that doesn’t quite fit my friend’s question.
teams %>% filter(yearID == 2018 & W >= 100) %>% arrange(-W)## yearID lgID teamID divID Rank G W L name
## 1 2018 AL BOS E 1 162 108 54 Boston Red Sox
## 2 2018 AL HOU W 1 162 103 59 Houston Astros
## 3 2018 AL NYA E 2 162 100 62 New York YankeesIn 2001, there were two teams that won 100 games, the Mariners and Athletics. The Mariners had 116 wins, in Ichiro Suzuki’s rookie year. The team lost to the 95 win Yankees in the ALCS. The As actually won 102 games but still finished 14 games back of the Mariners. They lost to the Yankees in the division series. The Yankees then lost in the World Series to the Diamondbacks in 7 games.
teams %>% filter(yearID == 2001 & W>=100) %>% arrange(-W)## yearID lgID teamID divID Rank G W L name
## 1 2001 AL SEA W 1 162 116 46 Seattle Mariners
## 2 2001 AL OAK W 2 162 102 60 Oakland AthleticsSome other teams included the Braves in their last year in the NL West, beating out the Giants 104-103 wins. Neither made it to the World Series, with the Blue Jays defeating the Phillies due to Joe Carter’s walk off home run in game 6.
teams %>% filter(yearID == 1993 & W>=100) %>% arrange(-W)## yearID lgID teamID divID Rank G W L name
## 1 1993 NL ATL W 1 162 104 58 Atlanta Braves
## 2 1993 NL SFN W 2 162 103 59 San Francisco GiantsThe 1962 season was also a cool story with the Giants and Dodgers both finishing with 101 wins. This was from before there were divisions in baseball and only one team would make the world series. As a result the two teams played an additional 3 game regular-season series with the Giants coming out ahead 2-1.
teams %>% filter(yearID == 1962 & W >= 100) %>% arrange(-W)## yearID lgID teamID divID Rank G W L name
## 1 1962 NL SFN <NA> 1 165 103 62 San Francisco Giants
## 2 1962 NL LAN <NA> 2 165 102 63 Los Angeles Dodgersteams %>% filter(yearID == 1961 & W >= 100) %>% arrange(-W)## yearID lgID teamID divID Rank G W L name
## 1 1961 AL NYA <NA> 1 163 109 53 New York Yankees
## 2 1961 AL DET <NA> 2 163 101 61 Detroit TigersAnother question is how often are there 100 game win teams in baseball?
First we can check how many times there are 100 win teams in a season.
teams %>% mutate(w100 = (W>=100)) %>%
group_by(yearID) %>%
summarize(n_teams = n(), w100teams = sum(w100)) %>%
arrange(-w100teams)## # A tibble: 150 × 3
## yearID n_teams w100teams
## <int> <int> <int>
## 1 2019 30 4
## 2 1942 16 3
## 3 1977 26 3
## 4 1998 30 3
## 5 2002 30 3
## 6 2003 30 3
## 7 2017 30 3
## 8 2018 30 3
## 9 1909 16 2
## 10 1910 16 2
## # … with 140 more rowsteams %>% mutate(w100 = (W>=100)) %>%
group_by(yearID) %>%
summarize(n_teams = n(), w100teams = sum(w100)) %>%
summarize(n_seasons = sum(n_teams), w100teams = sum(w100teams))## # A tibble: 1 × 2
## n_seasons w100teams
## <int> <int>
## 1 2955 109There have been 109 hundred win seasons in the 2955 baseball team seasons in the database.
teams %>% mutate(w100 = (W>=100)) %>%
group_by(yearID) %>%
summarize(n_teams = n(), w100teams = sum(w100)) %>%
summarize(n_seasons = sum(n_teams), w100teams = sum(w100teams)) %>%
summarize(w100teams/n_seasons)## # A tibble: 1 × 1
## `w100teams/n_seasons`
## <dbl>
## 1 0.0369That breaks down to about 3.7%. Given that there are 30 teams in the league, we would expect about 1 team to reach the 100 win plateau per year.