how to lie with statistics and probability n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
How to Lie with Statistics (and Probability) PowerPoint Presentation
Download Presentation
How to Lie with Statistics (and Probability)

Loading in 2 Seconds...

play fullscreen
1 / 17

How to Lie with Statistics (and Probability) - PowerPoint PPT Presentation


  • 134 Views
  • Uploaded on

How to Lie with Statistics (and Probability). Bruce Schmeiser Purdue University. IE230 April 29, 2011. Fifty-Year-Old Reference. “This book is sort of a primer in ways to use statistics to deceive.”. Acknowledgments Introduction The Sample with the Built-in Bias The Well-Chosen Average

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'How to Lie with Statistics (and Probability)' - candra


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
how to lie with statistics and probability

How to Lie with Statistics(and Probability)

Bruce Schmeiser

Purdue University

IE230

April 29, 2011

this book is sort of a primer in ways to use statistics to deceive
“This book is sort of a primerin ways to use statistics to deceive.”

Acknowledgments

Introduction

The Sample with the Built-in Bias

The Well-Chosen Average

The Little Figures That Are Not There

Much Ado about Practically Nothing

The Gee-Whiz Graph

The One-Dimensional Picture

The Semi-attached Figure

Post Hoc Rides Again

How to Statisticulate

How to Talk Back to a Statistic

slide4

Biased Sampling

  • 1948 Presidential election
  • 4 out of 5 dentists recommend Crest
  • Letters of recommendation
  • Purdue course evaluations
    • www.ratemyprofessors.com
slide5

Confusion about Averages

  • Mean versus median versus mode
    • Average Microsoft employee income
    • Average HBS graduating income
slide6

Confusion about Averages

  • Mean versus median versus mode
    • Average Microsoft employee income
    • Average HBS graduating income
  • Ill-defined experiment
    • Average family income
    • Average interstate speed
    • Inspection paradox
slide9

Misleading Figures

200 #

100 #

0 #

Men

Women

slide10

Changing Definitions

  • High blood pressure
  • Poverty level
slide11

Assume Equally Likely

  • Monte Hall
  • Lottery design
  • Slot machines
  • Dice: P(D1 + D2 = 3)= P(D1 + D2 = 7)
slide12

Correlation Does Not Imply Causality

  • South Seas Islands: Christianity and STDs
slide13

Correlation Does Not Imply Causality

  • South Seas Islands: Christianity and STDs
  • Good attitude and long life
slide14

Correlation Does Not Imply Causality

  • South Seas Islands: Christianity and STDs
  • Good attitude and long life
  • Hours of sleep and weight
slide15

Implicit Assumptions

St. Petersburg Paradox

I pay you $2X , where

X = “number of coin flips until head”

Then X = 1, 2, 3,… .

slide16

Implicit Assumptions

St. Petersburg Paradox

I pay you $2X , where

X = “number of coin flips until head”

Then X = 1, 2, 3,… .

Result:

E( $2X ) = Σ∞x=1 2xP( X = x )

= Σ∞x=1 2x( ½ ) x

= Σ∞x=1 1

= ∞

slide17

Implicit Assumptions

St. Petersburg Paradox

I pay you $2X , where

X = “number of coin flips until head”

Then X = 1, 2, 3,… .

Result:

E( $2X ) = Σ∞x=1 2xP( X = x )

= Σ∞x=1 2x( ½ ) x

= Σ∞x=1 1

= ∞

Why won’t you pay $10?