Fuel Efficiency Predictor

A simple Shiny application for estimating car fuel efficiency from vehicle weight, horsepower, and cylinders.

Fuel efficiency is easy to discuss but harder to estimate intuitively.

This app gives a novice user a simple way to ask:

• How does weight affect expected MPG?
• How does horsepower affect expected MPG?
• How do 4-, 6-, and 8-cylinder vehicles compare?

The app is intentionally small, interactive, and easy to evaluate.

The app uses the built-in mtcars dataset and fits a regression model in server.R.

model <- lm(mpg ~ wt + hp + factor(cyl), data = mtcars)
round(coef(model), 2)

 (Intercept)           wt           hp factor(cyl)6 factor(cyl)8 
       35.85        -3.18        -0.02        -3.36        -3.19 

The user's selections are passed into the model, and the predicted MPG is displayed reactively.

The Shiny interface includes three user inputs:

• A slider for vehicle weight
• A slider for horsepower
• Radio buttons for cylinder count

When the user changes any input, the server recalculates the prediction and updates both the MPG estimate and the comparison chart.

• The app has widget inputs.
• server.R performs a real calculation on user input.
• The calculated result is displayed in the web page.
• Documentation is included inside the Shiny app itself.
• This pitch contains embedded R code that is evaluated when the presentation is generated.

https://ld0574.shinyapps.io/fuel_efficiency_predictor/