Don’t Believe Everything You Think

The Six Basic Mistake People Make in Thinking

Thinking is Skilled work.People with untrained minds should no

more expect to think clearly and logically than people who have never learned and

never practiced can expect to find themselves good carpenters, golfers,

bridge players or pianists.

Science is aMETHOD,

not aSUBJECT

QUIZ

#1) In the past 20 years, violence in schools has:

A) IncreasedB) Remained about the sameC) Decreased

QUIZ

#2) In the past 20 years, violent crime in America has:

A) IncreasedB) Remained about the sameC) Decreased

QUIZ

• The answer to both was c) decreased.

• Individual stories have a powerful affect on how we see the world, but they do not accurately reflect it.

Six Common Mistakes

• People prefer Stories to statistics

Anecdote ≠ DataMany factors contribute to each individual

person or situation. This is why science uses statistics.

For example, an individual may smoke cigarettes for 80 years and die of an unrelated cause, but statistics show people who smoke are 8x more likely to have heart and lung disease.

The popular media usually reports both

sides of an issue; even if there is only one side.

Stories are often about conflict and the media looks for the conflict…

even if it has to inflate it…or make it up.

Quiz

#3) The following three numbers follow a rule. If you give 3 numbers, I will tell you whether or not they follow the same rule. Attempt to discover what the rule is:

2, 4, 6

Quiz

2, 4, 6The rule is: “Three positive whole numbers in

ascending order.”

Six Common Mistakes

• People prefer Stories to statistics• People seek to Confirm, not question, ideas

Science Thought

• Most people seek evidence to support.• In science, we attempt to disprove.• Nothing can EVER be proven. Cases may still

exist to falsify.

Lucy: I think your the most selfish human being on the planet. George: Well that's just silly. Have you met everybody on the planet?

-Sandra Bullock and Hugh Grant in Two Weeks Notice

The process of science is about viciously

weeding out the bad ideas and leaving the

good ones.

Science is:•Testable•Falsifiable•Repeatable

If you don’t question ideas, then you

cannot distinguish the useful from the

worthless.

Scientific “facts” are conclusions confirmed to such an extent that is reasonable to offer agreement…but this

assent is NEVER final.

There are no final answers in science—only varying degrees

of probability.

QUIZ

A B

#4) Which of the following is the most random?

QUIZ#5) What is the chance of a coin coming up

heads on a single flip?

#6) What is the chance of a coin coming up heads if I have already gotten 3 heads in a row?

#7) What is the chance of a coin coming up heads if I have already gotten 10 heads in a row?

QUIZ

#8) A popular ESP test uses five (5) symbol cards for the “reader” to try to identify. If each trial uses twenty-five (25) cards, how many would you expect by chance alone?

#9) Would it be evidence of psychic powers for someone to get nine (9) right?

QUIZ

A B

#4) A is the most random

QUIZ#5) 50%

#6) 50%

#7) 50%

#8) five (5)

#9) No

The Bell Curve

SOMEBODY has to in the top 0.1%: Million-to-one chances happen eight times a day in New York.

Six Common Mistakes

• People prefer Stories to statistics• People seek to Confirm, not question, ideas• People do not understand the role of chance

and coincidence in life

Chance: The Gambler’s Fallacy

• The roulette wheel has just hit four red numbers in a row….bet on black: it is “due”

• John has just hit four three-point baskets in a row...pass him the ball: he has a hot hand.

• The gambler has been winning at blackjack…keep playing: he’s hot.

• The gambler has been losing at blackjack…keep playing: he’s due.

What’s the chance?

• We must be aware of the power of chance and coincidence.

• Will you take this bet: At least two people in this room were born on the same day of the month.

• Would you take this bet: At least two students in my classes have the exact same birthday.

• BOTH have better than 75% chance.

Quiz

#10) Please write down the following sentence

Paris in thethe spring

Quiz:#11) Describe what you see:

Quiz:#12) Describe what you see:

Quiz:#13) Count the number of passes made by people in WHITE shirts.

PASSES

PASSES

Quiz answers

#10) Paris in the the spring

#11) Three partial circles (there is NO triangle)

#12) Faces? Vases? It’s both!

#13) Re-watch the video without counting…

Six Common Mistakes

• People prefer Stories to statistics• People seek to Confirm, not question, ideas• People do not understand the role of chance

and coincidence in life• People misperceive the world around them

Patterns

• We are pattern seeking. • The ability to see cause and effect has

enormous advantage• The ability, however, can be easily fooled.• Pareidolia-seeing patterns in random noise• Responsible for ghost sightings, etc.• We need to be careful to avoid seeing

patterns that do not exist.

Quiz#14) Consider the following:There is a contagious virus in the population. A

test exists for it that 100% accurate if you have it (it will never say you don’t if you do.)

The test has a 5% false positive rate (says you have it even though you don’t)

1 in 500 people have the virus.IF your test says you have it, what is the chance

that you ACTUALLY have it?

Quiz#15) Consider the following:Steve is very intelligent, but speaks quietly. He

is shy and withdrawn, but tries to be very helpful. He very orderly and pays attention to the details.

Which is most likely Steve’s Job: Farmer, Salesman , Airline pilot, Librarian, Actor?

Quiz Answers#14) 1 in 500 have the virus.

For every 500 tested, 1 has the virus5% test positive falsely (500 x 5%= 25)So 1 true positive + 25 false = 26 totalyour chance are 1/26 (4%) you really

have it!

#15) All are equally likely…

Six Common Mistakes

• People prefer Stories to statistics• People seek to Confirm, not question, ideas• People do not understand the role of chance

and coincidence in life• People misperceive the world around them• People over-simplify

Memorize this list

Quiz#16) Write down the list of words.

#17) Which Star Wars character was Mr. Colby posing with?

Quiz Answers#16) Sour, Nice, Candy, Honey, Sugar, Soda,

Bitter, Chocolate, Good, Heart, Taste, Cake, Tooth, Tart, Pie

#17) None. It was a Halo Costume!

Six Common Mistakes

• People prefer Stories to statistics• People seek to Confirm, not question, ideas• People do not understand the role of chance

and coincidence in life• People misperceive the world around them• People over-simplify• People have faulty memories

Selective Memory

• Psychics make hundreds of predictions.• Some, just be chance, turn out to be right.• People remember the few right predictions

and forget wrong ones.– Save a prediction issue of a magazine for one year– Compare/Count the “hits” and “misses”

Don’t ignore the negatives. Consider all the

evidence.

Scientific Thinking

• Statistics: individual stories do not make data • Science attempts to falsify• Science takes into consideration the role of

chance and coincidence in studies• Studies must be repeated to avoid perceptual

error• All possibilities considered, only evidence

matters

The Scientific Method

The Scientific Process