Media as a Context for Learning Computation

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Media as a Context for Learning Computation

• Mark Guzdial
• College of Computing/GVU

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Story

• Computer science education is in a sorry state
• Thats a serious problem for GVU
• The challenges we need to face
• The argument for a course in digital media
• Description of the course thats on-going now

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Computer Science Classes Today

• CS1 is one of the most despised courses for
  non-majors
• CS retention rates are lower than the rest of
  campus
• 65 for 1995 cohort, vs. 73 for Engineeering
• Drop-out rates near 50 at many institutions
• Female enrollment in CS is dropping nationally
• At Georgia Tech, were below the average

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Why?

• Tedious, boring, lacking creativity,
  asocial
• CS culture seems most attractive to white males.

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CS Freshmen Majors, Fall 2001
Number SAT avg(combined)
Female 38 1342
Male 303 1371
African-American 15 1349
Hispanic 2 1350
Caucasian 233 1379
Total 341 1368
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Why should GVU care?

• What is our vision of computation and new media?
• Should people just consume media? Or should they
  understand it? And even be able to create it?

In Alan Kays vision of the computer, the
Dynabook, programming itself is a medium
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The best uses for our technologies will come from
others

• Thomas Edison vs. D.W. Griffith
• If we want our technologies to become useful,
  they have to get out of our hands.
• It cant be just through applications
• That presumes that we the researchers know how
  the technologies should be used.
• Suggestion D.W. Griffith knew things that Edison
  didnt.

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Why should anyone care?

• In 1961, Alan Perlis argued that computer science
  is more important in a liberal education than
  calculus
• Calculus is about rates, and thats important to
  many.
• Computer science is about process, which is
  important to everyone

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The Challenges

• We have to motivate non-CS students to care about
  computing
• We have to make it social, creative, exciting,
  and not tedious
• Which is how many of us already see Computing,
  but thats not getting communicated

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Our Attempt Introduction to Media Computation

• A course for non-CS and non-Engineering majors
• International Affairs, STAC, Architecture,
  Management, Biology, etc.
• 120 students this semester,planning 400-600 in
  the Fall
• 2/3 female in this semesters CS1315
• Focus Learning programming within the context of
  media manipulation and creation

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Motivating the Computing

• As professionals, these students will often the
  use the computer as a communications medium.
• All media are going digital,and digital media
  are manipulated with software.
• Knowing how to program, then, is a communications
  skill.

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Programming as a Communications Skill

• Knowing how to program means to understand ones
  tools.
• Maybe means can transfer tool skills more easily
• Students already telling us that theyre excited
  to learn how PhotoShop works.
• And it means that, if you have to, you may be
  able to grow your own

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Programming as Communicating Process

• A program is a succinct, executable process
  description
• That makes valuable for explaining process
• We use examples from Biology and Management to
  make this point

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Python as the programming language

• Huge issue
• Use in commercial contexts authenticates the
  choice
• ILM, Google, Nextel, etc.
• Minimal syntax
• Looks like other programming languages
• Potential for transfer

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How the class was developed

• Created in response to recent unpleasantness
• On-line surveys, meetings with students
• Inspired in part by ECEs DSP First
• Developed with an advisory board from across
  campus Psych, HPS, Math, ECE, CETL
• Trialed in faculty workshop in mid-December

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Course Objectives

• Students will be able to read, understand, and
  modify programs that achieve useful communication
  tasks
• Not programming from a blank piece of paper
• Students will learn what computer science is
  about, especially data representations,
  algorithms, encodings, forms of programming.
• Students will learn useful computing skills,
  including graphing and database concepts

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Use a loop!Our first picture recipe
original
def decreaseRed(picture) for p in
getPixels(picture) valuegetRed(p)
setRed(p,value0.5)
Used like this gtgtgt file"/Users/guzdial/mediasour
ces/barbara.jpg" gtgtgt picturemakePicture(file) gtgtgt
show(picture) gtgtgt decreaseRed(picture) gtgtgt
repaint(picture)
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A Sunset-generating function

• How do we turn this beach scene into a sunset?
• What happens at sunset?
• Tried increasing the red, but that failed.
• New Theory As the sun sets, less blue and green
  is visible, which makes things look more red.

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A Sunset-generation Function
def makeSunset(picture) for p in
getPixels(picture) valuegetBlue(p)
setBlue(p,value0.7) valuegetGreen(p)
setGreen(p,value0.7)
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def clearRed(picture) for pixel in
getPixels(picture) setRed(pixel,0)
def greyscale(picture) for p in
getPixels(picture) rednessgetRed(p)
greennessgetGreen(p) bluenessgetBlue(p)
luminance(rednessbluenessgreenness)/3
setColor(p, makeColor(luminance,luminance,
luminance))
def negative(picture) for px in
getPixels(picture) redgetRed(px)
greengetGreen(px) bluegetBlue(px)
negColormakeColor(255-red,255-green,255-blue)
setColor(px,negColor)
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Using your personal pictures
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And messin with them
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Data-first

• Real users come to a user with data that they
  care about, then they (unwillingly) learn the
  computer to manipulate their data as they need.
• CS1315 can work the same.
• Students can bring their pictures, sounds, and
  movies as starting points for manipulations.

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Rough overview of Syllabus

• Defining and executing functions
• Pictures
• Psychophysics, data structures, defining
  functions, for loops, if conditionals
• Sounds
• Psychophysics, data structures, defining
  functions, for loops, if conditionals
• Text
• Converting between media, generating HTML,
  flattening media and saving to a database
• Movies
• Then, Computer Science

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Computer science as a solution to their problems

• Writing programs is hard! Are there ways to make
  it easier or shorter?
• Functional programming and recursion
• Object-oriented programming
• Movie-manipulating programs take a long time to
  execute. Why?
• Algorithmic complexity
• Why is PhotoShop so much faster?
• Compiling vs. interpreting

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Assignments encourage collaboration

• Homework are all collaborative
• Quizzes are preceded by nearly-identical,
  collaborative pre-quizzes
• Two take-home exams (programming assignments)
  are non-collaborative

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Assignments encourage creativity

• For several homework, the task is to manipulate
  media in some way, but we dont care what media
• Creating a collage, building an animation
• Encouraging homework results to be posted to
  CoWeb in galleries
• Purchasing Webcams to loan to students to create
  their own media

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These arent CMU CS undergrads

• Were realizing that these students are not like
  the ones in the Fisher Margolis class.
• Students who can get into CMUs CS program (often
  the computer experts in their families and
  schools) are not the same as non-CS and
  non-Engineering students at Georgia Tech.
• I type the command and nothing happens. The
  Enter key?
• Do I need a Zip disk to unpack a zip file?

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Tying it back to student goals and GVU

• Working with Jay Bolter (jay.bolter_at_lcc.gatech.edu
  ) and Diane Gromalas new course LCC 3404e
  Designing for the Internet
• Aimed at Freshmen and Sophomores
• Students learn to analyze and design Web sites
• Approach combines
• Visual design principles
• Information architecture and HCI
• CS1315 teaches the students the
  technologies,LCC3404e teaches them how to use
  the technology to communicate.

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Assessing the effort

• Comparing CS1321, COE1361, and CS1315 in terms of
  learning and motivation, broken out by gender and
  major
• Observational study of student performance to
  understand problems and strategies
• Interview study of impact on women

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Summary

• CS Education is in a sorry state,and fixing it
  is important to us and others
• Media Computation may be a useful context to
  motivate student performance
• Our class is aimed at addressing the challenges
  weve identified, and were trying it now

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Acknowledgements

• Course materials development Jason Ergle, Claire
  Bailey, David Raines, Joshua Sklare, Adam Wilson,
  Andrea Forte, Mark Richman, Matt Wallace, Alisa
  Bandlow.
• Assessment Andrea Forte, Rachel Fithian, Lauren
  Rich
• Thanks to Bob McMath and the Al West Fund, to GVU
  and CoC, and the National Science Foundation

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For further information

• Course CoWeb http//coweb.cc.gatech.edu/cs1315
• Where we planned the coursehttp//coweb.cc.gatec
  h.edu/mediaComp-plan
• guzdial_at_cc.gatech.edu

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def chromakey(source,bg) for x in
range(1,getWidth(source)) for y in
range(1,getHeight(source)) p
getPixel(source,x,y) My definition of
blue If the redness greenness lt blueness
if (getRed(p) getGreen(p) lt getBlue(p))
Then, grab the color at the same spot from the
new background setColor(p,getColor(getPixe
l(bg,x,y))) return source