library(tidyverse)We’ll continue working with banzuke dataset.
Read banzuke.csv with hard-coded column types:
df <- read_csv(
"banzuke.csv",
col_types = "ciccccDddcii"
)We’ll find all promotions to the rank of Yokozuna since 1983:
df %>%
# wrestlers with the rank of Yokozuna
filter(grepl("^Y", rank)) %>%
# find earliest tournament (basho) for each wrestler
group_by(id) %>%
summarise(
rikishi = last(rikishi, order_by = basho),
basho = min(basho)
) %>%
# only wrestlers who were promoted after 1983.01 (first basho in this dataset)
filter(basho > min(df$basho)) %>%
# sort
arrange(basho)
## # A tibble: 14 x 3
## id rikishi basho
## <int> <chr> <chr>
## 1 4104 Takanosato 1983.09
## 2 4136 Futahaguro 1986.09
## 3 1339 Hokutoumi 1987.07
## 4 1350 Onokuni 1987.11
## 5 1342 Asahifuji 1990.09
## 6 1 Akebono 1993.03
## 7 2 Takanohana 1995.01
## 8 3 Wakanohana 1998.07
## 9 4 Musashimaru 1999.07
## 10 878 Asashoryu 2003.03
## 11 1123 Hakuho 2007.07
## 12 1111 Harumafuji 2012.11
## 13 1219 Kakuryu 2014.05
## 14 1235 Kisenosato 2017.03I was very surprised to find an old video I shot on a flip phone in January 2007. This is Hakuho, a young ozeki, still on the way to his promotion in July: https://www.youtube.com/watch?v=mu3vS2qHFAA