INF 397 Day 1R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Fall, 2003
cell: 512-657-3924
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
i
There are three kinds of lies: lies, damned lies, and statistics.
Benjamin Disraeli (1804 – 1881), British politician
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Statistics are like a bikini. What they reveal is suggestive, but what they conceal is vital.
Aaron Levenstein, U.S. politician
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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The statistics on sanity are that one out of every four Americans is suffering from some form of mental illness. Think of your three best friends. If they're okay, then it's you.
Rita Mae Brown, U.S. author
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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First . . .
There are two components of this and any class: Instruction and Evaluation.
Let’s get the evaluation out of the way, early.
Need one volunteer.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Finger length is a good (and quick!) indicator of intelligence.
One volunteer – measure your finger length in cm.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Hmmmm . . .
Everyone in the class will get a grade of “C”
But still, we can continue with the “instruction” part of the course.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Just THIS person isn’t too smart.
OK, everyone measure your right index finger.
From the top (last) crease in your hand, to the tip of the finger.
Write down the length, in cm.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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How to measure
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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You HAVE to wager it:
Turn it heads UP on your desk if you think that two people in this classroom share a birthday, and heads DOWN if you think that no two people share a birthday.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Questionnaire
1 – Strongly disagree
5 – Strongly agree
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Your first name and last initial.
Your birth month and day (I don’t care about the year).
The length of your finger, in cm.
The number of Major League Baseball games you’ve seen, in person.
Your answer (the number) to the questionnaire question.
One favorite hobby.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Now, an experiment
I will hand you each a slip of paper. Please read it an do NOT let anyone else read it.
Women receive a pink slip of paper.
Men receive a blue slip of paper.
After everyone has read his/her slip of paper and refolded it, I’ll show some letters of the alphabet, one at a time, for one second each.
After the last one, I’ll say “Go,” and ask you to write down the letters, in order.
Any questions?
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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J
F
M
A
M
J
J
A
S
O
N
D
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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In order!
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Answers
J
F
M
A
M
J
J
A
S
O
N
D
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Total
Men
Women
Total
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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. . . is a statistical wizard?
. . . has experience conducting research?
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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What are some things that you know?
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Method of Authority
Method of Reason
Modeling
Trial-and-error
Intuition
belief on the basis of experience
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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What are some decisions you made today?
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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After this class . . .
You’ll know something about how scientists (information scientists) gather new information.
AND you’ll be good at evaluating information others offer you.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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3 – Critical skepticism.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Rabbit pie story.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Reliability. (“Oh, just measure it however.”)
Sampling – picking a representative sample and then generalizing to a larger population
Why larger samples are better
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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How to represent a group of numbers, meaningfully.
Frequency distributions
Probability
Correlation
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Different measurement scales
Experimental design
Inferential statistics (is THAT number really bigger than THIS number?)
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Ph.D. in cognitive psych from UT-Austin
Bell Labs for 3 years
IBM-Austin for 11 years
Co-founded Austin Usability 3 years ago
Previously adjunct faculty member at UT; Have taught at UT, Rutgers, Huston-Tillotson, SWTSU
Newly an assoc. prof. in the UT School of Information
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Objectives
To arm you with a scientist’s skepticism, and a scientist’s tools to conduct research and evaluate others’ research. The student who successfully completes this course will understand:
1 – descriptive statistics, and how to represent a collection of numbers
2 – how to design a good experiment (and evaluate if someone else has)
3 – inferential statistics and hypothesis testing
4 – other techniques human beings use to gain new information, such as qualitative methods.
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Review syllabus
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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What’s up with “Psychology”?
R. G. Bias | School of Information | SZB 562BB | Phone: 512 471 7046 | rbias@ischool.utexas.edu
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Homework
Bring in one claim that you hear in the next week. On the news, in your reading, in an ad, wherever.
Buy books. (Co-op says they’re in.)
No office hours next Tuesday.
See you next week.