Position, Location, Place and Area

Aspects of addressing space:

Reference: relative (with reference to space or other objects) or absolute (agreed to by general consensus)
Specificity and Uncertainty: the extent of the addressable space
Scope: placement at different scales
Context: with or without context

	Position	Location	Place	Area
Reference	Absolute (e.g. coordinate system)	Absolute (e.g. room number)	Relative, placement in a room (inside)	Relative, placement in an aggregation of rooms
Specificity/ Uncertainty	Depends on the device providing the position	Certain, defined by the physical borders (walls)	Uncertain, defined by the functional space of an object (e.g. desk)	Uncertain, defined by a more general notations (floors, parts of building)
Scope	Defined by a reference frame	Contains places	Contained in locations	Contains locations
Context	No context	Context	Context	Context
Example	“I am at 28.2314° - 33.4577°”	“I am in the living room”	“I am at the photocopier”	“I am on the second floor”

Four concepts of placement:

Position: pin-point placements
Location: smallest physically defined space in a building
Place: placement of particular object and the uncertain (functional) space around it
Area: generalised space or sub-space, containing multiple addressable locations

Framework modelling indoor space composed of:

Agents: entities that navigate space, access resources and perform activities
Resources
Space: entirety of the enclosed environment to be navigated
Sub-spaces
- Inert spaces: inaccessible by agents
- Free spaces:
  - Allow agents to move through them
  - Contain resources
  - Host activities
Modifiers:
- Can be applied to sub-spaces, agents and resources
- Define the environment of a sub-space, a sub-space can be encumbered by multiple modifiers
Activities

Network models: graph structure G(V, E) representing indoor space