do_possession: Compute when possessions start

In BAwiR: Analysis of Basketball Data

Compute when possessions start

Description

Compute when the possession starts for each team in a game.

Usage

do_possession(data, period_sel, time_point_start)

Arguments

data	Play-by-play prepared data from a given game.
period_sel	Period of interest. Options can be "xC", where x=1,2,.... If NULL, no filtering is done.
time_point_start	Starting time point of the lineup.

Value

Data frame. This is the meaning of the columns that might not be explanatory by themselves:

time_start: Time point when the action starts. time_end: Time point when the action ends. poss_time: Duration of the possession. possession: Indicates when the possession starts. This is encoded with the Spanish word inicio (start, in English). points: Number of points scored from a given action.

Note

1. A possession lasts 24 seconds in the ACB league.

2. Actions are given in Spanish. A bilingual basketball vocabulary (Spanish/English) is provided in https://www.uv.es/vivigui/docs/basketball_dictionary.xlsx.

3. The game_code column allows us to detect the source website, for example, https://live.acb.com/es/partidos/103389/jugadas.

Author(s)

Guillermo Vinue

Examples

## Not run: 
library(dplyr)
df0 <- acb_vbc_cz_pbp_2223

day_num <- unique(acb_vbc_cz_pbp_2223$day)
game_code <- unique(acb_vbc_cz_pbp_2223$game_code)

# Starting players:
acb_games_2223_sl <- acb_vbc_cz_sl_2223 %>%
  dplyr::filter(period == "1C")

# Prepare data:
df1 <- do_prepare_data(df0, day_num, 
                       acb_games_2223_sl, acb_games_2223_info,
                       game_code)

teams_game <- sort(unique(df1$team))
team_sel <- teams_game[1]

data <- df1
data <- data %>%
  mutate(row_num = row_number()) %>%
  mutate(time_point = ifelse(nchar(time_point) < 5, paste0("0", time_point), time_point))

# Filter by team:
data1 <- data %>%
  filter(team == team_sel)

# Set also the opponent team:
team_opp <- setdiff(unique(data$team), team_sel)

# Add the last row of games' data to have the real final 
# game score in case it is not available:
last_row_game <- data[nrow(data),]

last_row_game$time_point <- "00:00"
last_row_game$player <- NA
last_row_game$action <- NA
last_row_game$team <- team_sel

data1 <- bind_rows(data1, last_row_game)

# Get players out:
pl_out <- c(1, which(data1$action == "Sale de la pista"), nrow(data1))

i <- 1
data2 <- data1 %>%
  slice(pl_out[i]:pl_out[i + 1]) 

nr <- nrow(data2)

# Lineup:
lineup <- data2 %>%
  filter(action != "Sale de la pista") %>%
  # Avoid actions that are assigned to teams: 
  filter(player != team_sel) %>%
  distinct(player) %>%
  pull()

# Identify when the possessions start:
data2_rival <- data %>%
  filter(team == team_opp) %>%
  filter(between(row_num, data2$row_num[1], data2$row_num[nr]))

data3 <- rbind(data2, data2_rival) %>%
  arrange(row_num) %>%
  na.omit()

data4 <- do_possession(data3, NULL, "10:00") 

## End(Not run)

BAwiR documentation built on Feb. 27, 2026, 5:07 p.m.