GIS for Transportation: Principles, Data and Applications

1.5 Next Week's Webinar



Next week we will have a webinar with Mr. Michael Ratcliffe. Michael is Assistant Division Chief for Geographic Standards, Criteria, Research, and Quality in the Census Bureau’s Geography Division, where he is responsible for geographic area concepts and criteria, address and geospatial data quality, and research activities. During his tenure at the Census Bureau, he has worked in both the Geography and Population Divisions, on a variety of geographic area programs, including urban and rural areas, metropolitan and micropolitan statistical areas, and other statistical geographic areas, and has led staff engaged in product development and dissemination. In addition to his work at the Census Bureau, he is an adjunct professor at George Washington University, where he teaches Population Geography. Prior to that appointment, he was an adjunct instructor at the University of Maryland-Baltimore County. Mr. Ratcliffe holds degrees in geography from the University of Oxford and the University of Maryland.

Geographic Areas Used by the Census Bureau

The Census Bureau defines many different geographic areas which can be used to organize and aggregate data. The areas the Census Bureau uses can be divided into those which are legally defined and those which are not. The Census Bureau refers to non-legally defined areas as statistical areas.

From top to bottom include: Nation, Regions, Divisions, States, Counties, Census Tracts, Block Groups, Census Blocks.
Standard Hierarchy of Census Geographic Entities

Watch the following tutorial (15 minutes) which provides an overview of the geographic areas the Census Bureau uses and the relationships between them.

Assignment 1-5 (10 points)

Based on your review of Census geographies and our speaker's biographical information, submit a write-up in M.S. Word format (no more than 300 words in length) to Assignment 1-5 in Canvas which addresses the following items:

  1. Based on your review of Census geographies, describe the difference between a legal or administrative geography and a statistical geography. (1 point)
  2. List 3 legal/administrative geographic areas the Census Bureau uses as well as 3 statistical areas they use. (1 point)
  3. The smallest geographic area the Census Bureau uses is the block. In rural areas, census blocks are larger than in urban areas. Why do you think the Census Bureau is careful about not making a block too small? How many blocks were defined for the 2010 decennial census? (2 points)
  4. Describe some characteristics of a Census Tract. Specifically, what is relatively uniform within a Census Tract? What is the average population in a Census Tract? (2 points)
  5. Some legal boundaries have interesting histories. What is unique about the Kentucky state boundary and how did it come about? (Hint: search for the "Kentucky Bend") (2 points)
  6. Come up with 2 - 4 questions for next week's speaker. (2 points)