Lecture 4: Spatial Analysis (Vector)

Spatial Analysis

A set of techniques for analyzing spatial data.

Dependent Results

The results of spatial analysis depend on the locations of the objects being analyzed.

GIS Software Requirements

Requires access to both the locations of objects and their attributes.

Intravariable Analysis

Performed on a single data set.

Intervariable Analysis

Performed on two or more data sets.

Querying

Method of data retrieval from a GIS database or analyzed data.

Buffer

Creation of a zone of interest at specified distance from input layer in spatial analysis.

Point Entity Buffer

A circular buffer zone.

Line Entity Buffer

An elongated buffer zone.

Polygon Entity Buffer

A buffer zone that maintains the shape of the original polygon but is larger.

Point Distance Tool

Calculates distance from each point in one feature class to all points in another feature class.

Near Tool

Adds attributes to a point feature class containing distance and identifiers of the nearest points or lines.

Thiessen Polygons

Creates polygons of areas closest to each feature, representing influence or catchment areas.

Vector Overlay Analysis

Creates a new spatial data layer from two or more old data layers.

Georeferenced Layers

Data layers that must be in the same coordinate system and cover the same area.

Spatial Join

Involves matching rows from one layer to another based on spatial relationships.

Topologically Correct Data Layers

Layers where lines meet at nodes and polygon boundaries are closed.

Distance/Proximity Analysis

Evaluates how close features are to one another and calculates various aspects of proximity.

Zone of Influence

The area surrounding a feature that is influenced by it, such as in the context of Thiessen polygons.

Crime Incidence Analysis

Usage of point distance tool to analyze the relationship between crime occurrences and police locations.

Attribute Fields

Fields added to a feature class containing data about features, such as distance to the nearest point.

Feature Identifier

An identifier associated with a feature in a GIS database.

Catchment Area

The area from which a feature can influence or attract other features.

Spatial Data Layer

A layer representing spatial data which can be analyzed and manipulated in GIS.

Operations Sequence in GIS

The ordered steps followed during spatial analysis in GIS.

Point Feature Class

A type of GIS layer where data consists of point locations.

Elongated Buffer Zone

A buffer zone created around line entities.

Centrally Located Buffer

A buffer zone that radiates outwards evenly from a central point.

Polygonal Buffer

A buffer zone that replicates the original polygon's shape but is larger.

Data Retrieval

The process of obtaining data from a database or analysis tool.

Search Radius

The specified distance within which distances are calculated between features.

Integrated Data Layers

Layers that can be combined to perform more complex spatial analyses.

Geographical Information System (GIS)

A system designed to capture, store, manipulate, analyze, manage, and present spatial or geographic data.

Data Attributes

The descriptive information related to the features in GIS.

Spatial Relationships

Relationships between objects based on their locations in space.

Output Feature Class

The resulting class of features derived from processing input feature classes in GIS.

Distance Calculation

A mathematical determination of space between geographic features.

GIS Database

A structured collection of data specifically designed for storage, analysis, and visualization in GIS.

Buffer Creation Distance

A specified distance used to create a buffer around an entity.

Feature Class

A collection of similar spatial features that share the same geometry type.

Spatial Decision Support

A process in GIS that assists in decision-making based on spatial data.

Spatial Analysis Techniques

Various methods utilized to analyze spatial data for insights.

Geographical Partitioning

The division of space into distinct areas based on geographical features.

Data Overlay

The process of placing multiple data layers on top of each other for analysis.

Analysis of Spatial Data

Evaluation of data that is associated with specific geographic locations.

Spatial Data Attributes

Characteristics or properties assigned to spatial data in GIS.

Coordinate System

A reference system used to locate and represent features in GIS.

Data Consistency

The requirement that overlapping data layers must be accurate and coherent.