Guofeng Cao

CyberInfrastructure and Geospatial Information Laboratory

Department of GeographyNational Center for Supercomputing Applications

(NCSA)University of Illinois at Urbana-Champaign

Overview of Geog 480 Overview of Geog 480

Course DescriptionCourse Description• This course is intended to introduce students to

basic principles in the rapidly growing field of Geographic Information Science (GIScience) and commonly used methods in spatial analysis. The course will be held in a lecture format combined with hands-on projects. The emphasis is on the concepts and principles that underlie the development of GIS and its intelligent use. The knowledge that students gain in this course will be general and will not be limited to a specific GIS product.

SurveySurvey• Name, major, year• What do you expect to learn from this class? • GIS experiences (courses taken, projects

participated, etc.)• Programming experiences (programming

languages, databases, and etc)• Open Source experiences

o Unix/linux like operating system?

• Note: Don’t be scared, it would be totally fine if you don’t have such experiences.

Class Information Class Information • Instructor: Guofeng Cao

(http://www.cigi.uiuc.edu/guofeng)o Lectures: Tues/Thurs 3:30pm-4:50pm (Davenport Hall 338)o Office Hours: Tues/Thus: 2:00pm -3:30pm (Davenport Hall 316)

• Prerequisites:o Geog 379 or consent of instructoro General Background: Knowledge on GIS, Cartography, Database and information

system will help understand the course materials.

• Course website:o http://www.cigi.uiuc.edu/guofeng/geog480.htm

• Textbook:o Worboys, M. and Duckham, M. 2004. GIS – A Computing Perspective, Second Edition.

New York, NY: CRC Press.o Smith, M. D, Longley, P. and Goodchild, M. F. 2012. Geospatial Analysis – A

Comprehensive guide (free)o Other reference materials

Course WorkCourse Work• Two midterm exams: 40% (20% each)• Course projects:

o The project will be divided into four stages, and report of each stage plus lecture related problems considered as four assignments (15% each * 4 = 60%); the first stage starts from end of week3

o The project will be evaluated based on (1) technical innovation, (2) thoroughness of the work, and (3) clarity of presentation

o Team composition: teams must include no more than 4 students and 2 graduate students

Topic Coverage of Geog 480Topic Coverage of Geog 480• Concepts of GIS (Textbook: Chap. 1 – 9)

o Databaseo Spatial conceptso Geospatial Data Modelso Representationso Spatial Analysiso Spatial Queryo Architectureo Interfaceo Spatial Uncertainty

• Hands-on Tutorials on open source GISo Why bother using open source tools?o PostGIS (open source spatial database)o Geoserver (open source geospatial data sharing)o OpenLayers (free maps for the web )

Research Frontiers in GIScienceResearch Frontiers in GIScience• Spatiotemporal dynamics• Social media analysis• Volunteer geographic information• Spatiotemporal statistics (data mining)• Semantic geospatial web• “Big” spatiotemporal data• Cyberinfrastructure-enabled GIS (CyberGIS)• High performance spatiotemporal computing• …

Useful linksUseful links• Cyberinfrastructure and Geospatial Information

Laboratory• CyberGIS Speaker Series• ESRI International User Conference

o July 8 - 12 , San Diego Convention Centero Student Assistantship Program

• Includes registration, accommodation, meals, • Apply online: http://www.esri.com/careers/students/user-

conference-student-assistants

• ESRI Summer Internship Program

IntroductionIntroduction

• Information systems: an association of people, machines, data, and procedures working together to collect, manage, and distribute information of importance to individuals or organizations

• Geographic information system (GIS): a computer-based information system that enables capture, modeling, storage, retrieval, sharing, manipulation, and presentation of geographically referenced data

• Geographic Information Science (GISc, or GISci, GIScience): studies the theory behind the development, use and application of GIS

• Geospatial data: geographically referenced data

What is GISWhat is GIS

Elements of GISElements of GIS• Databases elements• Data Processing element• Data storage and retrieval element• Data sharing element• Data presentation element• Spatial reasoning element• Accuracy, precision, and reliability• Spatiotemporal element

Data and informationData and information• Context: the structure of interrelationships

between data and how data is collected, processed, used, and understood within an applicationo Understanding the data model and the limitations of

data, are elements of the context for data

• Data is only useful, taking on value as information, within its context

information = data + context

The Nature of Geographic DataThe Nature of Geographic Data• Spatial (and temporal) Context: “Everything

is related to everything else, but near things are more related than distant things”o Waldo Tobler’s First Law (TFL) of geographyo nearby things are more similar than distant thingso phenomena vary slowly over the Earth's surfaceo Compare time series

The Nature of Geographic DataThe Nature of Geographic Data• Implications of Tobler’s First Law:

o We can do samplings and fill the gap using estimation procedures (e.g. weather stations)

o Spatial patterns o Image a world without TFL:

• White noise• No polygons (how to draw a polygon on a white noise map?)

The Nature of Geographic DataThe Nature of Geographic Data• Spatial Heterogeneity

o Earth’s surface is non-stationaryo Laws of physical sciences remain constant, virtually everything else

changes• Elevation, • Climate, temperatures• Social conditions

o Global model might be inconsistent with regional models:• Spatial Simpson’s Paradox

The Nature of Geographic DataThe Nature of Geographic Data• Fractal Behavior

o What happens as scale of map changes?o Coast of Maine

• Implications:o Volume of geographic features tends to be underestimated

• Lengths of lines• Surface areas

• End of this topic