Package 'jpaccidents'

Download the traffic accident data

Description

download_accident_data() downloads the file of traffic accident data provided the National Police Agency.

Usage

download_accident_data(type, download_dir = getwd(), years = 2023)

Arguments

type	A character string specifying the type of data to download: one of "main", "supp", or "highway".
download_dir	A character string specifying the directory to save the downloaded files (default: getwd()).
years	An integer or vector of integers specifying the years of the data to download. Available years are 2019 to 2023 (default: 2023).

Details

The traffic accident data are divided into the following types:

• "main" : Basic data on traffic accidents (honhyo).

• "supp" : Additional data related to the "main" data (hojuhyo).

• "highway" : Data on traffic accidents on highways (kosokuhyo).

Use the type argument to specify which data type to download.

Value

A character vector of file paths for the downloaded files (invisibly).

Examples

## Not run: 
# Download the main data for 2023
download_accident_data("main", "download-dir-path", 2023)

# Download the supplementary data for 2023
download_accident_data("supp", "download-dir-path", 2023)

# Download the highway data for 2019 to 2023
download_accident_data("highway", "download-dir-path", 2019:2023)

## End(Not run)

---

Filter accident data by categories

Description

These functions filter accident data based on the specified categories.

Usage

filter_accident_type(data, accident_type)

filter_road_shape(data, road_shape)

Arguments

data	A accident_data object.
accident_type	A vector of specifying the accident type to filter. Must be one of the following values: "vehicle_to_pedestrian": Vehicle-to-pedestrian collision "vehicle_to_vehicle" : Vehicle-to-vehicle collision "single_vehicle" : Single-vehicle accident "train" : Train accident
road_shape	A vector of specifying the road type to filter. Must be one of the following values: "intersection_roundabout" : Roundabout intersection "intersection_other" : Regular intersection "near_intersection_roundabout": Area near a roundabout "near_intersection_other" : Area near an intersection "tunnel" : Tunnel "bridge" : Bridge "curve" : Curve or bend in the road "single_road" : Straight single road "railroad_crossing_type1" : Type 1 railroad crossing "railroad_crossing_type3" : Type 3 railroad crossing "railroad_crossing_type4" : Type 4 railroad crossing "general_traffic_area" : General traffic area

Value

A filtered accident_data object.

Examples

## Not run: 
# Extract accidents where vehicle collided with pedestrian
vehicle_to_pedestrian_collisions <- data %>%
  filter_accident_type("vehicle_to_pedestrian")

# Extract accidents involving vehicle-to-vehicle collisions
vehicle_to_pedestrian_collisions <- data %>%
  filter_accident_type("vehicle_to_pedestrian")

# Extract accidents that occured on curved roads
curved_road_accidents <- data %>%
  filter_road_shape("curve")

## End(Not run)

---

Filter accident data by collision patterns

Description

filter_collision_pattern() filters accident data based on primary and secondary impact conditions for each party involved in the accident.

Usage

filter_collision_pattern(
  data,
  primary_impacts,
  secondary_impacts = NA_character_
)

Arguments

data	A list containing accident data.
primary_impacts	A vector specifying the initial collision points (primary impact) for each involved party.
secondary_impacts	A vector specifying the subsequent collision points (secondary impact) for each involved party (default: NA_character_).

Details

The values of primary_impacts and secondary_impacts are following:

• "no_impact" : No impact

• "front" : Front of the vehicle

• "right" : Right side of the vehicle

• "rear" : Rear of the vehicle

• "left" : Left side of the vehicle

• "front_right": Front right of the vehicle

• "rear_right" : Rear right of the vehicle

• "rear_left" : Rear left of the vehicle

• "front_left" : Front left of the vehicle The order of values in primary_impacts and secondary_impacts corresponds to the party order (party_order).

Value

A list containing filtered accident data.

Examples

## Not run: 
# Filter accident data by cases indicating head-on collisions
head_on_collisions <- filter_collision_pattern(data, c("front", "front"))

# Filter accident data by cases indicating rear-end collisions
rear_end_collisions <- filter_collision_pattern(data, c("rear", "front"))

## End(Not run)

---

Merge accident data

Description

merge_accident_data() merges multiple accident_data objects into a single accident_data object.

Usage

merge_accident_data(...)

## S3 method for class 'accident_data'
merge_accident_data(...)

## S3 method for class 'list'
merge_accident_data(data_list, ...)

Arguments

...	accident_data objects to merge.
data_list	A list of accident_data objects to merge.

Value

A merged accident_data object.

---

Read accident data from CSV files

Description

read_accident_data() reads accident data from multiple CSV files, processes each file, and combines the data into three categories:

• accident_info: Basic accident information including date, location, and conditions

• person_info : Information about individuals involved in the accidents

• highway_info : Information specific to accidents that occurred on highways/expressways

Usage

read_accident_data(file_paths)

Arguments

file_paths

A character vector of file paths to the CSV files.

Value

A list containing three data frames (accident_info, person_info, and highway_info).

Examples

## Not run: 
# Read main and supplementary data for 2023
read_accident_data(c("example/honhyo_2023.csv", "example/hojuhyo_2023.csv"))

## End(Not run)

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