Intro to
Shiny

Day 23

Prof Amanda Luby

Carleton College
Stat 220 - Spring 2025

Demo

Shiny: High level view

Every Shiny app has a webpage that the user visits,
and behind this webpage there is a computer that serves this webpage by running R.

When running your app locally, the computer serving your app is your computer.

When your app is deployed, the computer serving your app is a web server.

Shiny vs. plotly

Shiny graphs need to be “connected” to RStudio or an Rstudio server
- Why? Data sets are rewrangled and a new graphic is drawn
plotly isn’t changing the underlying data set/stats being displayed, can be displayed on webpage without an RStudio session

Getting started

Option 1: Embed a shiny plot/table in HTML docs

Need add runtime: shiny to your YAML header

Option 2: Can create an app.R file with a ui() and server() function

For template
New Files > R Markdown > Shiny - New Files > Shiny Web App

What’s in an app?

library(shiny)
ui <- fluidPage(
  inputs,
  outputs
)


server <- function(
    <reactive functions and code to render output>) {
  ...
}
`

shinyApp(
  ui = ui, 
  server = server
)

User interface controls the layout and appearance of app
Server function contains instructions needed to build app

Data: Ask a manager

Source: Ask a Manager Survey via TidyTuesday

This data does not reflect the general population; it reflects Ask a Manager readers who self-selected to respond, which is a very different group (as you can see just from the demographic breakdown below, which is very white and very female).

Some findings here.

Data: `manager-survey.csv`

manager <- read_csv("https://stat220-s25.github.io/data/manager-survey.csv")
manager

# A tibble: 26,232 × 18
   timestamp          how_old_are_you industry  job_title additional_context_o…¹
   <chr>              <chr>           <chr>     <chr>     <chr>                 
 1 4/27/2021 11:02:10 25-34           Educatio… Research… <NA>                  
 2 4/27/2021 11:02:22 25-34           Computin… Change &… <NA>                  
 3 4/27/2021 11:02:38 25-34           Accounti… Marketin… <NA>                  
 4 4/27/2021 11:02:41 25-34           Nonprofi… Program … <NA>                  
 5 4/27/2021 11:02:42 25-34           Accounti… Accounti… <NA>                  
 6 4/27/2021 11:02:46 25-34           Educatio… Scholarl… <NA>                  
 7 4/27/2021 11:02:51 25-34           Publishi… Publishi… <NA>                  
 8 4/27/2021 11:03:00 25-34           Educatio… Librarian High school, FT       
 9 4/27/2021 11:03:01 45-54           Computin… Systems … Data developer/ETL De…
10 4/27/2021 11:03:02 35-44           Accounti… Senior A… <NA>                  
# ℹ 26,222 more rows
# ℹ abbreviated name: ¹additional_context_on_job_title
# ℹ 13 more variables: annual_salary <dbl>, other_monetary_comp <dbl>,
#   currency <chr>, currency_other <chr>, additional_context_on_income <chr>,
#   country <chr>, state <chr>, city <chr>,
#   overall_years_of_professional_experience <chr>,
#   years_of_experience_in_field <chr>, …

Ultimate goal

https://minecr.shinyapps.io/manager-survey

Your turn

10:00

Final details

Shiny apps need to be “connected” to RStudio or a remote RStudio server
You can deploy shiny apps online
- using Posit’s cloud server (free/fee) - https://www.shinyapps.io/
- creating a shiny server

Intro to Shiny