Download presentation
Presentation is loading. Please wait.
Published bySarai Henley Modified over 10 years ago
1
Cheat or Honest? An Experiment Department of Statistics Rachel Fewster
2
Catch the Cheats! I am a fraud investigator, you are the suspects! Each group picks a status: Honest or Cheat You can change the status that you pick if you like, but WRITE DOWN your new status on your slip (no erasing the evidence!!)
3
HONEST GROUPS: 1.Pick a column on the atlas sheets: Population, Area sq km, or Area sq miles 2. Pick a start-point wherever you like 3. Copy down 100 entries from your column: just the first two digits is enough. E.g. for 2 691 write 2600 (dont round it) For 782 write 780.
4
CHEATING GROUPS: 1.Make up the numbers out of your head! 2.Again just use two digits, e.g. 530, 72000, 8800000, … 3.You can use the atlas sheets as a guide to range of numbers, but you must MAKE YOUR NUMBERS UP.
5
Now for the investigation! 1.UNDERNEATH your numbers … Make out a TALLY LIST for FIRST DIGITS in your output:
6
123456789123456789 I I III I IIII I II III 1.Make out a TALLY LIST for FIRST DIGITS in your output:
7
123456789123456789 I III I IIII I II III 2. Rewrite the tally as numbers 3. Title First Digit 113014123113014123 First Digit
8
123456789123456789 I III I IIII I II III 113014123113014123 First Digit 7. Fold your paper, tear off the tallies from the rest. 8. Write your name on the tallies section and hand in!
9
Can we catch the cheats ??? See the R demonstration at: http://www.stat.auckland.ac.nz/~fewster/benford/
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.