scenarios for statistics

Scenarios for Statistics

Susan Holmes, Statistics, StanfordBiometrie INRA, Montpellier, France.

Thanks to Brad Efron, Persi Diaconis, NSF CUE.

EXPO :D. Ewing R. Gill

Introductory level statistics class aimed at æsthetes.

“Maths for fuzzies”?

No calculus requirement, (nor an inclination for

maths expected).

Familiarity with the computer wasacquired in stages:

1. Using the browser

The class notes were made available on a class web

page:

2. Running applets

There are many existing applets on the web for teaching

probability, we used an array of ones from Buffon’s

needle to Monty Hall. (Probability by surprise project).

3. Collecting Data

Newspapers and experiments.

4. Using Flash to do some statistical analyses

The first permutation tests were executed using a

simple press button interface on data already entered

into the program:

5. Making one simple Flash animation scene

An animation for “paired comparisons ”

Michael Areinoff’s Histogram

Anita Lillie’s Histogram

Sara Flores’ Stem and leaf

6. Publishing Flash animations on the web

• html files −− > swf files

• upload files

7. Interactive Flash

8. Making a whole Flash movie with several scenes

This involved making complete storyboards containing

the concepts and how they were illustrated as well as

joining the scenes together.

9. Writing Flash actionscript programs to analyze

data

More ambitious students programmed with

actionscript.

Bootstrap of a Regression(2000 Elections)

Enter ones own data and analyze it, as in this bootstrap

flash animation, written by Anita Lillie shows.

Creative Assignments

As homeworks and final projects, we asked the

students to write their own animations to illustrate

some of the concepts we did in class:

Matt Law’s correlation

Roberto Fernandez’ outlier

Dina Leyte’s movie

Danny Jacobs’ Shakespeare Bootstrap

Rob Fernandez’ final project

Flash Actionscripts

Here are some of the possibilities that were added

with version 5 of flash and that has made mathematical

functions possible:

Math.random, Math.floor, Math.round, Math.sin, Math.cos,

Math.abs etc...

see examples at

http://flash5actionscript.com/samplepiechart.php

A summary of the experiment

None of these students wanted to use spreadsheets

or statistical software so Flash was an appealing

alternative especially because no other course on

campus catered to this arty crowd. The audience was

coaxed into using the computer to program because

Flash was written originally for designers, with no prior

programming necessary at all.

To see for yourselves, an overview of the projects

and homeworks, please visit our Student Sampler.

Where do we go from here?

Changing the students’ attitudes in an elementary

statistics class from passive consumers to active

creators can definitely change their experience.

Creating an animation to illustrate a concept meant

that not only is the concept understood, but also-

students acquire the focus to extract the few important

features that need to be shown in an animation. The

artistic and creative components kept them interested

even when the statistics seemed arduous.

10. Using statistics programs to analyze data

• Open source (research level) statistics program:

• Real Datasets available on the web (Computational

Biology and Genetics, later ).

11. Intricate Analysis of the Physics behind the

animations Coin Flip 6

Fitted Ellipses

Clever coin

References

[1] S. Bhangal,(2000), Foundation Actionscript.

Friends of ED, Birmingham, UK.

[2] M. Wooldridge, (2001), Teach Yourself Visually

Flash 5, Marangraphics Inc/ Hungry Minds.

[3] B. Efron and Susan Holmes,

(2001), Scenarios for Statistics:

Stat30, Webpage:http://www-

stat.stanford.edu/˜susan/courses/s30/

[4] Susan Holmes, (2001), Teaching with Flash,

Statistical Computing and Graphics Newsletter,

volume 12, 1,

http://www-stat.stanford.edu/˜susan/scgn/v121.pdf/