get_crime_data {crimedata}

Get Data from the Open Crime Database

Description

Retrieves data from the Open Crime Database for the specified years. Latitude and longitude are specified using the WGS 84 (EPSG:4326) co-ordinate reference system.

Usage

get_crime_data(
  years = NULL,
  cities = NULL,
  type = "sample",
  cache = TRUE,
  quiet = !interactive(),
  output = "tbl"
)

Arguments

years

A single integer or vector of integers specifying the years for which data should be retrieved. If NULL (the default), data for the most recent year will be returned.

cities

A character vector of city names for which data should be retrieved. Case insensitive. If NULL (the default), data for all available cities will be returned.

type

Either "sample" (the default), "core" or "extended".

cache

Should the result be cached and then re-used if the function is called again with the same arguments?

quiet

Should messages and warnings relating to data availability and processing be suppressed?

output

Should the data be returned as a tibble by specifying "tbl" (the default) or as a simple features (SF) object using WGS 84 by specifying "sf"?

Details

By default this function returns a one-percent sample of the 'core' data. This is the default to minimize accidentally requesting large files over a network.

Setting type = "core" retrieves the core fields (e.g. the type, co-ordinates and date/time of each offense) for each offense. The data retrieved by setting type = "extended" includes all available fields provided by the police department in each city. The extended data fields have not been harmonized across cities, so will require further cleaning before most types of analysis.

Requesting all data (more than 17 million rows) may lead to problems with memory capacity. Consider downloading smaller quantities of data (e.g. using type = "sample") for exploratory analysis.

Setting output = "sf" returns the data in simple features format by calling sf::st_as_sf(..., crs = 4326, remove = FALSE)

For more details see the help vignette: vignette("introduction", package = "crimedata")

Value

A tibble containing data from the Open Crime Database.