Chapter 5: Evidence

Question 1

Evidence

Answer 1

any new fact that supports a possibility under investigation (possibility is hypothesis = H)

Question 2

Evidence Test

Answer 2

is this fact more likely if H is true or if H is not true?

Question 3

Independent

Answer 3

suppose that one claim is true. Does that affect how likely the other claim is? If not, the two claims are independent.

Question 4

The First Rule of Evidence

Answer 4

evidence should increase our confidence in a hypothesis

Question 5

The Strength of Evidence

Answer 5

A test that involves comparing the following:

A) suppose H is true: how likely is this?
B) suppose H is false: how likely is this?

Comparing these two is the strength test

Question 6

Strength Test Extremes

Answer 6

Evidence is maximally strong: the evidence entails the hypothesis, so the inference is deductive

Question 7

Evidence and Probability

Answer 7

Likelihood of claim: degree of confidence

Confidence can be expressed on spectrum ranging from 0 to 1

0 = certainty that claim is not true

1 = certainty that claim is true

0.5 = equal confidence in claims being true or false

Question 8

What is NOT Meant by Probability

Answer 8

Probability is not restricted to future events

Probability is not a statistical generalization about classes of events

Probability of a claim is simply your degree of confidence in that claim

Question 9

Degree of Confidence

Answer 9

Degree of confidence is expressed as a percentage, fraction, or decimal between 0 and 1

Probability of H and probability of not-H should add up to 100%

Question 10

Importance of Strength Test

Answer 10

To test suppositional strength

Forces us to consider the opposite (what would we expect to observe if H were false?)

Prevents one-sided testing

Question 11

One-Sided Strength Testing

Answer 11

Only paying attention to how likely the evidence would be if the claim were true than if it were false

Question 12

Opposite Evidence Rule

Answer 12

If E is evidence for H, then not-E is evidence for not-H

Question 13

Selection Effects

Answer 13

factors that systematically select which things we can observe (makes evidence unreliable)

Question 14

Confidence in a Hypothesis Depends on Two Things:

Answer 14

1. How strong the evidence is
2. How confident we were before getting the evidence

Question 15

Survival Bias

Answer 15

an error in which attention is paid only to those entities that have passed through (or “survived”) a selective filter.

Question 16

Attrition Bias

Answer 16

a selection effect in which some patients drop out of a research study, weakening the data and survey

Question 17

Selective Memories

Answer 17

Treating the ease with which things come to mind as an indication of how common/probable those things are

Question 18

Serial Position Effect

Answer 18

the tendency to remember the very first and last events in a series

Question 19

Selective Noticing

Answer 19

tendency to notice examples that fit hypotheses we have heard (confirming instances)

Even if we do not believe hypothesis

Question 20

Media Biases

Answer 20

News outlets and other media biased toward engaging content

Question 21

News and Fear

Answer 21

News outlets choose to cover “newsworthy” stories (stories that generate more emotional impact)

Leads to more dramatic stories getting coverage

Question 22

Echo Chamber

Answer 22

the feedback loop that occurs when our sources of information and opinions have all been selected to support our opinions/preferences

Question 23

Publication bias:

Answer 23

the tendency for academic books and journals to publish research that is surprising in some way

Question 24

File Drawer Effect

Answer 24

researched not even bothering to publish “boring work”

(selection effect caused by researchers themselves)