Chapter 1
Maps come in many forms, think of paper maps that show minimal information such as roads and towns. GIS maps have spatial pictures and can be created to show in depth information. Chapter 1 is about advance mapping where you can find patterns, trends and work towards solving problems.
Some key terms I found interesting listed below.
Map Features: GIS uses three main shapes to draw everything. Points, which are tiny dots for certain locations. Lines, connected paths such as pathways and roads. Polygons, shapes with boundaries that outline an area such as a county.
Discrete Data, has clear edges like property lines.
Continuous Data, flows across space with out hard borders such as temperature
It is amazing that almost everything can be mapped. How can you protect private information from becoming part of this system? I wonder if people can use this tool to commit crimes?
Chapter 2
This chapter involves plotting locations and spotting groups clustered together.
Mapping where things are located.
Single Symbol Mapping, giving every single item the same icon and color
Clusters, tight bunches of dots
Outliers, lone dots far away from everything else
If you are going to map everything your map could look messy. Map scale has to be right so that your information can be interpreted. Are there sources to help pick the best map scale?
Chapter 3
Talks about mapping numbers and the importance of calculating them correctly before putting them on your map. You do not want incorrect information available to interested parties.
Data grouping, how you split up numbers into groups before picking colors
Normalization, fixing raw counts so a fair comparison can be made.
Choropleth Map, classic shaded map where areas are colored lighter or darker based on their numbers
So you should never map raw totals for large regions. You need to make sure detail is incorporated or your map will just show basic information.
How do you choose color shades?