7 - Practice Problem

Poverty Rate

Now you learned how to join and visualize data in QGIS. Let's see if you can perform the same task in a different dataset!


  • ACS_poverty_CLN.csv
  • census_county.shp


  1. Join the census county shapefile to the poverty data
    • Hint: Think which column (variable) you will need to use to join two datasets?
  2. Export joined dataset
  3. Visualize the poverty rate
    • Natural Breaks (Class = 4)

Sample Outcome


Try to make a map without looking at this first. Stuck? Click buttons below!

  1. covid_county_property -> Properties -> Joins
    • Join Layer: ACS_income_CLN
    • Join field: GEO_ID
    • Target field: AFFGEOID
    • Custom field_name prefix: income
  2. Open attribute table to check the data is joined properly

  1. covid_county -> Property -> Export -> Save Vector layer As
    • Format: ESRI Shapefile
    • Filename:covid_poverty_county
      • Be sure to specify the file location!
  2. Remove joins
    • covid_county -> Properties -> Joins -> Click "-" sign

Why you need to change the data type??
Becasue to map the data using Graduated symbols, the data needs to be numerical!
  1. covid_poverty_country -> Attribute table -> Field Calculator
    • Output field name: pov_rrate
    • Output field type: Decimal number (real)
    • Under Field and values, select pov_rate

  1. covi_poverty_country -> Properties -> Symbology
    • Graduated
    • Value:pov_rrate
    • Color ramp: Reds
    • Mode: Natural Breaks
      • Class: 4