Using R in Used Car Search

Recently I was looking to buy a used car. I was using the Edmunds website to estimate the true market value of a used car. It has a nice click through interface where it guides you to input make, model, year etc. and will give an estimated value. While the interface is nice, it would be nice to get a broader view across years, models etc. Luckily, Edmunds also has a developer API which is nicely documented. Here I am listing my basic attempts at using the developer API to get some data into R and get exploratory plots of car value by year. For using this API, you need to get a API key (specifically the vehicle API key is used here).

The code used for creating the plots below can be found here.

The plots below show the market value across styles for a given model/make of a car by year. The y axis in these plots is the Edmunds estimated True Market Value for a typically equipped vehicle (not sure how they define it). The bars in the graph span the range of market value.

TMV for Honda Accord


TMV for Toyota Corolla


Edmunds also makes several adjusments for car condition, car mileage and additional car options. The plot below show the TMV adjustment for each option for a 2008 Toyota Corolla (LE 4dr Sedan (1.8L 4cyl 4A)

adjOptionThe plot below shows the adjustment made for car condition for a 2008 Toyota Corolla (LE 4dr Sedan (1.8L 4cyl 4A)


The plot below shows the mileage adjustment again for  a 2008 Toyota Corolla (LE 4dr Sedan (1.8L 4cyl 4A)


This entry was posted in R. Bookmark the permalink.

6 Responses to Using R in Used Car Search

  1. Anon says:

    Very nice!

  2. Thanks for this information i would also like to share valuation of car depends on year,model and made style if we consider its objective but for subjective matters it will depend on appearance and condition.even if two cars look and identical in age there value may be different on secondary market.that is why proper car .
    To know more please visit
    valuation of car

  3. herveywilna says:

    The facts are describe in this post such really interesting . You can check your car valuation by using this kind of tips and analysis . Using R is interesting way to get a good search result for your car.

  4. Pingback: Using R in Used Car Search - R Project Aggregate

  5. phil says:

    I would love to pick your brain on some car data visualization project for our website. Feel free to contact me if you are interested. I think data visualisation in car buying decision could be a great asset for our readers. looking forward to hear back from you.

    • Jack says:

      Phil, I have been thinking about this topic as well – out of curiosity, did you have any specific data visualization in mind for how data could be helped with car buying decisions? Based on your website I imagine you are thinking larger scale visualization since you cover all types of cars.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s