Lab 3: Data Formats and Models

1. What is a data model? Describe the two most commonly used data models.
 
      A data model is a model that illustrates a part of earth on a GIS. The two most common data models are Vector and Raster.

2. What is topology and why is it important?

          Topology is the relationship between points and lines on a data model. The main difference between it and the spaghetti model is that topology maintains relationships even with molding.

3. What type of data model would be best for representing hillside slope? Justify your answer.
 
      Raster, because the grids in raster maps are better suited for elevation than lines on a Vector data model.

4. Describe the relationship between spatial detail and cell dimension with regard to raster models.

       The less cells available, the less spatial detail is illustrated. In retrospect, small, abundant cells provide more spatial detail.

5. What are the four types of attribute data? Give an example of each.
  
          Nominal - place name
          Ordinal - ranking of nominal data
          Interval - temperature
          Ratio - sea depth

6. List two types of vector data file formats.
    
   .shp & .eOO

7. List two types of raster data file formats.

       .img & .TIFF

8. You can do all of the following in ArcCatalog EXCEPT:
 
      c. Select features

9. In the Chapter 4 exercises, does the World.mdb geodatabase contain a feature dataset?
    
      yup

10. What are the names of the feature classes contained in the World.mdb geodatabase?
 
      cities, countries, disapp_area, world30

11. What data format does the flight_path.lyr layer file reference?
  
     .shp

12. What are two ways to add data to an ArcMap document?
 
          1. Click on the (+) Add Data button
          2. Drag and drop from ArcCatalog

13. How many features (records) exist in the dissap_area feature class?
  
      699!

III. Complete the ESRI online module “Basics of the Geodatabase Data Model” and
post a screenshot of the certificate.