Assignment 5: R APIs and Databases

1 Accept Assignment on Github Classroom

1. Accept Assignment 5 on Github Classroom.

2. Clone this assignment to your computer.

3. Intitialize your own renv environment.

2 Set up “secrets.r” file

• Copy the “secrets-template.r” file to a new “secrets.r” file

This will be where you will store your personal API keys and passwords.

I have already added “secrets.r” to the “.gitignore”, so it should not be tracked or pushed to Github.

3 FRED API

4 Pull FRED Series

• Get an API Key from FRED. Save it in your “secrets.r” file.

You will need to use the fredr package for this section.

• Pull the following data series

  • Real GDP: “GDPC1”
  • Rhode Island Unemployment Rate: “RIUR”
  • US-Euro Spot Exchange Rate: “DEXUSEU”
  • One more series of your choice, look around FRED’s website

• Make a chart for each series

• Combine all of the charts using patchwork

• Save the combined chart to a pdf in the output folder, call it “fred-chart.pdf”

4.1 Vintage FRED

• Choose one of the series from above, and pull it using a vintage date.¹

• Redo the chart with the new data, and use patchwork to make a combined figure comparing the current and vintage series.

• Save the combined figure to a pdf in the output folder, call it “fred-vintage-chart.pdf”

¹ See the coding example for this lecture if you are confused.

5 tidycensus API

• Request a Census API key: https://api.census.gov/data/key_signup.html

  • Save it to your “secrets.r” file

• Install the sf package

  • Check their documentation if you have trouble².

• Install the tidycensus package

• Pull median household income: “B19013_001” from the ACS³

  • But choose a different state than Rhode Island

• Create a map with the data and ggplot2

• Save the map to a pdf in the output folder, call it “tidycensus-map.pdf”

² You likely need to install something called ‘gdal’ in the terminal.

³ Same as the example in the slides.

(Optional) Mapview

If you want to try making one of those interactive maps, install the package mapview and give it a go.

6 (Optional) Connect to WRDS Database

• First, get access to WRDS through Brown Univesrity Library

Warning

This takes 1-2 days!

• Once you have an account, make sure you can log into WRDS online: https://wrds-www.wharton.upenn.edu

• Then add your account username and password to the “secrets.r” file.

• Then open up the “get-wrds-data.r” script

  • The connection to the WRDS database should already work
  • Try running the example in the code (same as what we saw in class)
  • Try finding another database to connect to and pull a subset of the data
    • I’d suggest looking around on the WRDS website to see what data is available

7 Submit

Commit your code and output and push to Github!