In kanga1988/kangakola_coursera_R_pkg: Far Data Analysis

library(farsdataanalysis)

PURPOSE

The purpose of this vignette is to describe how this package work.The farsdataanalysis package is built for educational purposes as part of the final peer review assignement of the Johns Hopkins coursera course "Bulding R package". The package allows the user to make the file name that will be used to do the followings:

• Load single or multiple years of FARS data
• Summarise (count the number of fatalities) for each year or multiple years by selecting only variables MONTH and year
• Map fatality counts for each month and year of corresponding USA State.The package will map fatal traffic accidents from 2013-2015 using data from the National Highway Traffic Safety Administration (NHTSA) Fatality Analysis Reporting System (FARS).

DATA

The data source is the National Highway Traffic Safety Administration (NHTSA) Fatality Analysis Reporting System (FARS) data. FARS data is available for every year since FARS was established in 1975.

More details and suplementary information can be found at this location. NHTSA FARS Manuals & Documentation page.

Here is the snapshot of sample data for 2014 witht its data structure and dimension

fars_data_2014 <- make_filename(2014)
fars_data_2014_a <- fars_read(fars_data_2014) 
dim(fars_data_2014_a)
fars_data_2014_a

CREATING THE FILENAME FOR FARS DATA

To load the FARS data file using this package, we suggest that you use make_filename command with the required year (203,2014, 2015). This will create a file name that meet FARS data naming standars and will enable the user to load data as required.

fars_data_2014 <- make_filename(2014)
fars_data_2014

LOADING FARS DATA FOR SINGLE YEAR

To look fatality data for a single year, it is advise to use fars_read_years() function with a single year as input. This function will trim the tbl_df data to only two columns: MONTH and year. The function will returns a list of one or multiples tibbles element of two variables : MONTH and year which contain the listing of the month and year for each fatality.

fars_data_2014 <- fars_read_years(years = 2014)
fars_data_2014[[1]]

LOADING FARS DATA FOR MULTIPLE YEARS

To look for multiple years fatalities, we suggest the use of a vector of years as argument for the function fars_read_years() as follows: fars_read_years(years = c(2013,2014,2015)) or fars_read_years(2013:2015). Again, this will returns a list of tbl_df as described for single year file.

fars_data_3y <- fars_read_years(years = 2013:2015)
fars_data_3y

SUMMARIZING FARS DATA

The fars_summarize_years() function take the same argument as the fars_read_years(), and produces a summary of the simple counts of fatalities by month and year:

fars_data_summary <- fars_summarize_years(2013:2015)
fars_data_summary

MAPPING FATALITIES

Finally, the fars_map_state function takes a state ID number and a year, and map state's fatalities location. The function required the maps package to be loaded.

For a list of the state ID numbers, see page 26 of the FARS Analytical User's Guide (2015).

library(maps)
fars_map_state(12, 2014)
fars_map_state(39, 2014)

kanga1988/kangakola_coursera_R_pkg documentation built on May 28, 2019, 2:48 p.m.