| epa2021 {openintro} | R Documentation | 
Vehicle info from the EPA for 2021
Description
Details from the EPA.
Usage
epa2021
Format
A data frame with 1108 observations on the following 28 variables.
- model_yr
- a numeric vector 
- mfr_name
- Manufacturer name. 
- division
- Vehicle division. 
- carline
- Vehicle line. 
- mfr_code
- Manufacturer code. 
- model_type_index
- Model type index. 
- engine_displacement
- Engine displacement. 
- no_cylinders
- Number of cylinders. 
- transmission_speed
- Transmission speed. 
- city_mpg
- City mileage. 
- hwy_mpg
- Highway mileage. 
- comb_mpg
- Combined mileage. 
- guzzler
- Whether the car is considered a "guzzler" or not, a factor with levels - Nand- Y.
- air_aspir_method
- Air aspiration method. 
- air_aspir_method_desc
- Air aspiration method description. 
- transmission
- Transmission type. 
- transmission_desc
- Transmission type description. 
- no_gears
- Number of gears. 
- trans_lockup
- Whether transmission locks up, a factor with levels - Nand- Y.
- trans_creeper_gear
- A factor with level - Nonly.
- drive_sys
- Drive system, a factor with levels. 
- drive_desc
- Drive system description. 
- fuel_usage
- Fuel usage, a factor with levels. 
- fuel_usage_desc
- Fuel usage description. 
- class
- Class of car. 
- car_truck
- Car or truck, a factor with levels - car,- 1,- ??,- 1.
- release_date
- Date of vehicle release. 
- fuel_cell
- Whether the car has a fuel cell or not, a factor with levels - N,- NA.
Source
Fuel Economy Data from fueleconomy.gov. Retrieved 6 May, 2021.
See Also
epa2012
Examples
library(ggplot2)
library(dplyr)
# Variable descriptions
distinct(epa2021, air_aspir_method_desc, air_aspir_method)
distinct(epa2021, transmission_desc, transmission)
distinct(epa2021, drive_desc, drive_sys)
distinct(epa2021, fuel_usage_desc, fuel_usage)
# Guzzlers and their mileages
ggplot(epa2021, aes(x = city_mpg, y = hwy_mpg, color = guzzler)) +
  geom_point() +
  facet_wrap(~guzzler, ncol = 1)
# Compare to 2012
epa2021 |>
  bind_rows(epa2012) |>
  group_by(model_yr) |>
  summarise(
    mean_city = mean(city_mpg),
    mean_hwy  = mean(hwy_mpg)
  )