vignettes/fars_vignette.md

In afortuny/fars: Package for FARS accident data analysis

title: "Fars" author: "Alan Fortuny" date: "February 16, 2018" output: html_document vignette: > %\VignetteEngine{knitr::knitr} %\VignetteIndexEntry{Title of your vignette} %\usepackage[UTF-8]{inputenc}

The fars package contains a set of functions for analysis of data from FARS - Fatality Analysis Reporting System. FARS is a nationwide census providing NHTSA, Congress and the American public yearly data regarding fatal injuries suffered in motor vehicle traffic accidents. [1]

Package functions

There are five exported functions available:

• fars_read()
• make_filename()
• fars_read_years()
• fars_summarize_years()
• fars_map_state()

Now we give a short description with examples how to use the functions. For the purposes of these examples we will use data from FARS, years 2013-2015, that can be found in the package directory under \extdata folder.

Read FARS data files

The function fars_read() provides a way how to read data from a file path provided as an argument. It returns a tibble with loaded data:

filename <- system.file("extdata/accident_2015.csv.bz2", package = "fars")
fars_read(filename)

Get the file name per year

The function make_filename() create the string filename based on the year from which we want to extract the information

make_filename(2015)

Months and years of each observarion

The function fars_read_years() read and store the month and year column for each of the years provided as argument.

setwd(system.file("extdata", package = "fars"))
fars_read_years(2013)

Summarize number of accidents

The next function fars_summarize_years() takes a vector or list of years (numeric/integer values) as an argument and if the corresponding files with data are available, it returns a pivot table with number of accidents per year and month. The data files need to be located in the working directory.

setwd(system.file("extdata", package = "fars"))
fars_summarize_years(2013:2015)

Plot accident locations

The last function available in the package, fars_map_state() takes a state index and year as arguments and returns a plot of the state with accident locations. The state indices need to correspond available indeces from the data set. Here are some examples:

setwd(system.file("extdata", package = "fars"))
fars_map_state(45, 2015)

afortuny/fars documentation built on May 7, 2019, 3:13 p.m.