SO432, Geographical Information Systems

Exam 2, Fall 2011



10@ 4 points



Short answers

 5 @ 12 points







 Read the directions carefully.  You have a selection of questions for the definitions and the short answers.

 Quality of your answers is important.   For full credit you should use correct terminology, and show that you understand the concepts involved.  Demonstration of understanding, and placing you answer in the context of GIS, is much more important than finding a random sentence from the book describing or defining the term, which will be an average answer.

 All work on this exam is individual.  You may not any materials (books, notes, computers, calculators), and you may not use IM, texting, talking, or any other means to communicate with other individuals.

Definitions:  define 10 of the 12 terms with a concise sentence that clearly shows your understanding of the term.  Each is worth 4 points.

1)      Triangulation: See new help file page

2)      Affine transformation: to register image/scanned map without any registration, but for which the geometry is simple.

3)      Quadrangle: See new help file page

4)      Focal operations: 4 skips

5)      Map algebra:

6)      Stream mode digitizing:

7)      Image registration:

8)      One person, one vote:

9)      Gerrymandering:

10)  Normal lighting direction:

11)   Reproject data:

12)  USGS:

The next few pages contain 5 questions, each of which is worth 12 points.  You can answer on the page or on the back of one of the pages. You must answer all 5.  For each answer you should clearly show that you understand the principles and use appropriate terminology.


1.     Is there an objective way to define the best districts for government representatives?  Why or why not?  Does GIS help or hinder the process?



2.  How can the computer compute slope, aspect, and reflectance?  Are these geometrically related?  See new help file page on Hillshade/reflectance map


3.  When you digitize on screen, discuss two factors that determine the accuracy with which you can records points and lines.



4.  Which provides better options for smart display of a database, Google Earth or a GIS program?  Are there any workarounds?  Discuss this in terms of a database with the following fields, and thousands of records:




YEAR--the building was built

FUNCTION--residence, business, social, educational

FLOORS--number of floors


MATERIAL--brick, stone, timber



5.  Why do you have to worry about getting the correct UTM zone for your map projection?  How can you tell if you have the wrong UTM zone?