1. Theme-on-theme Selection
ArcView_module_9
May 14, 1:30 PM

2. Outline What is Spatial overlay? Spatial overlay in ArcView
Theme-on-theme selection: concepts & terms
Theme-on-theme selection: steps

3. Spatial Overlay Figuring out the relationships between map features
Near (e.g. UB south campus is near subway station)
Within (e.g. This store is within Erie county)
Intersect (e.g. Erie canal runs across New York state)

4. Spatial overlay in ArcView
Theme-on-theme selection
Map features are selected based on the spatial relationships between themes
Spatial Join
Two theme tables are joined based on spatial relationships

5. Theme-on-theme selection
Since the operation is performed over the relationships between themes, we need at least two themes (in general).

6. Theme-on-theme selection
Select US jurisdictions adjacent to the Canadian border
Select census blocks within the 10 miles from the new site of casino
Select states that intersect Interstate 90
Target Theme
Selector Theme

7. Theme-on-theme selection
The selection is made in the target theme based on the spatial relationship between target and selector theme so
Target theme is an active theme

8. Theme-on-theme selection
If some features have been selected in the selector theme, the operation will be performed on the selected features
Otherwise, it will be performed on all features.

9. Steps in ArcView 1. Make the Target Theme active
2. Choose the Select By Theme… from the Theme menu

10. Steps in ArcView In the Select by Theme dialog box,
3. Select the Selector Theme
4. Choose spatial relation type from the dropdown list
5. Choose a selection method