Module 4 - Manley Ch 5 - Evidence

Question 1

What is “evidence” in reasoning?

Answer 1

Evidence is any observation or fact that helps assess the likelihood of a hypothesis being true or false, guiding reasoning across disciplines.

Question 2

What are the two key tests for assessing evidence?

Answer 2

The Evidence Test: Is the observation more likely if the hypothesis is true or false?

The Strength Test: How much more likely is the evidence if the hypothesis is true than if it is false?

Question 3

What is the first rule of evidence?

Answer 3

Evidence should increase our confidence in a hypothesis, though the degree of increase depends on the evidence’s strength.

Question 4

How do we measure the strength of evidence?

Answer 4

By comparing how likely the evidence is if the hypothesis is true versus if it is false, expressed as a “strength factor.”

Question 5

What is a “strength factor”?

Answer 5

The number of times more likely the evidence is given that a hypothesis is true compared to when it is false (e.g., a strength factor of 10 means the evidence is 10 times more likely if the hypothesis is true).

Question 6

What is the significance of a strength factor of less than 1?

Answer 6

It indicates that the evidence is less likely if the hypothesis is true, making it evidence against the hypothesis.

Question 7

How confident should we be in a hypothesis when evidence has a strength factor of 10?

Answer 7

Confidence depends on both the strength of the evidence and prior confidence in the hypothesis; a strength factor of 10 strongly supports the hypothesis but doesn’t multiply confidence by 10.

Question 8

When is evidence maximally strong for a hypothesis?

Answer 8

When the evidence could only occur if the hypothesis is true, making the probability of the evidence under the hypothesis being false equal to zero.

Question 9

What is “independent evidence”?

Answer 9

Observations that are equally likely whether a hypothesis is true or false, providing no support for or against the hypothesis.

Question 10

How does the strength of evidence relate to suppositional strength in arguments?

Answer 10

The stronger the evidence provided by premises, the greater the suppositional strength of the argument’s conclusion.

Question 11

What happens if evidence supports both for and against a hypothesis?

Answer 11

The overall support depends on the relative strength of the evidence for each side.

Question 12

What is the relationship between evidence and reasoning?

Answer 12

Responsiveness to evidence is central to reasoning, helping us update our beliefs and evaluate hypotheses effectively.

Question 13

How does the strength test compare pieces of evidence?

Answer 13

By quantifying how much more likely each piece of evidence is under the hypothesis versus its negation, enabling precise evaluation.

Question 14

How is “probability” defined in the context of this text?

Answer 14

Probability is our degree of confidence in a claim, represented as a value between 0 (certainly false) and 1 (certainly true).

Question 15

What is the relationship between probability and confidence?

Answer 15

Probability expresses how confident we are that a claim is true, such as being 50% confident equating to a probability of 0.5.

Question 16

What rule ensures probabilities are consistent?

Answer 16

The probabilities of a hypothesis (H) and its negation (not-H) must add up to 1 (e.g., if H is 0.8, not-H must be 0.2).

Question 17

What is the Strength Test in evaluating evidence?

Answer 17

It compares how likely the evidence is if the hypothesis (H) is true versus if it is false, giving a strength factor.

Question 18

What is the Opposite Evidence Rule?

Answer 18

If a piece of evidence (E) supports a hypothesis (H), then the absence of that evidence (not-E) supports not-H.

Question 19

What is “Heads I win, Tails we’re even” bias?

Answer 19

A cognitive bias where evidence supporting a view is accepted, but evidence against it is dismissed or ignored.

Question 20

Why is considering the opposite view important in evaluating evidence?

Answer 20

It helps avoid biased evaluation by forcing us to think about how likely evidence would be if the hypothesis were false.

Question 21

What is Suppositional Strength?

Answer 21

The degree to which premises support a conclusion if the premises are true, evaluated as evidence for the conclusion.

Question 22

Why must both sides of the Strength Test be evaluated?

Answer 22

Only considering how evidence fits with H (and not how it fits with not-H) can lead to overestimating its support for H.

Question 23

Can evidence against a hypothesis be weaker than evidence for it?

Answer 23

Yes, evidence against H might be weaker than evidence for H, but it is still evidence that should adjust our confidence.

Question 24

How does cognitive bias affect evidence evaluation?

Answer 24

Bias can cause us to dismiss evidence against our views or overvalue evidence that aligns with them.

Question 25

What is the value of assigning probabilities to unique events?

Answer 25

It reflects our confidence in the event, even though the event is already determined (e.g., "It’s probably raining").

Question 26

Why should probabilities of a claim reflect relevant statistical facts?

Answer 26

Confidence in a claim (e.g., a coin toss being heads) should be informed by known probabilities (e.g., 50%).

Question 27

What does failing to find supporting evidence imply?

Answer 27

A lack of supporting evidence provides some evidence against a claim, with strength depending on how much was searched.

Question 28

How can we counter confirmation bias when faced with evidence?

Answer 28

By considering how we would react to the opposite evidence and adjusting our confidence accordingly.

Question 29

What happens if evidence could only occur if the hypothesis is true?

Answer 29

The evidence is maximally strong for the hypothesis because it could not arise under not-H.

Question 30

What is a selection effect?

Answer 30

A factor that filters which observations are available, potentially making evidence unreliable if the filtering isn't recognized.

Question 31

What is survivor bias?

Answer 31

A type of selection effect where only successful or surviving cases are observed, leading to misleading conclusions about success rates or outcomes.

Question 32

How does attrition bias affect studies?

Answer 32

It occurs when participants drop out of a study in ways that bias the results, such as happier or unhappier individuals being more likely to leave.

Question 33

What is selective noticing?

Answer 33

Paying more attention to evidence that supports a hypothesis while ignoring or failing to register disconfirming evidence.

Question 34

What is the availability heuristic, and how does it relate to memory?

Answer 34

A cognitive shortcut where things that come to mind easily are assumed to be common or probable, influenced by emotional intensity, framing, or event order.

Question 35

What is the serial position effect?

Answer 35

The tendency to remember the first and last items in a series or event better than the middle ones.

Question 36

What is media bias in the context of selection effects?

Answer 36

Media outlets tend to prioritize content that engages viewers, often favoring stories that elicit fear or rage, regardless of their actual relevance or proportional impact.

Question 37

How does the media's focus on fear-inducing stories affect public perception?

Answer 37

It skews perceptions of risk by overemphasizing rare, dramatic events (e.g., shark attacks, mass shootings) while underreporting common, less sensational causes of death (e.g., heart disease, car accidents).

Question 38

What is the impact of the media on perceptions of violent crime in the U.S.?

Answer 38

Despite violent crime rates declining since the 1970s, the media’s focus on isolated violent events leads most Americans to believe crime rates are rising.

Question 39

How does survivor bias relate to media coverage of terrorism or mass shootings?

Answer 39

The media amplifies the visibility of dramatic, isolated events while neglecting widespread, less spectacular causes of death, creating a distorted view of risks.

Question 40

What is an example of misaligned media coverage vs. actual risks?

Answer 40

Public mass shootings receive disproportionate media attention compared to car accidents, which cause vastly more deaths annually (less than 100 vs. 35,000).

Question 41

How does the 24-hour news cycle amplify selection effects?

Answer 41

Continuous coverage emphasizes isolated, fear-inducing events, reinforcing public misconceptions about their frequency and importance.

Question 42

What is an example of misaligned media coverage vs. actual risks?

Answer 42

Public mass shootings receive disproportionate media attention compared to car accidents, which cause vastly more deaths annually (less than 100 vs. 35,000).

Question 43

How do our evolutionary instincts misjudge threats in modern life?

Answer 43

System 1 processes, evolved for small tribal communities, are overwhelmed by large-scale information networks, leading us to overreact to rare, dramatic threats and underestimate common risks.

Question 44

What cognitive illusion is created by media-driven fear?

Answer 44

System 1 overreacts to dramatic events, while System 2 recognizes the statistical reality, causing a mismatch in perceived vs. actual risks.

Question 45

How might proportional news coverage influence public behavior?

Answer 45

It could reduce fear of rare events and shift focus toward preventing major risks, like heart disease and cancer, through healthier lifestyle choices.

Question 46

Why do stories about shark attacks elicit more fear than deer accidents?

Answer 46

Sharks are perceived as more dramatic and emotionally impactful, appealing to System 1, even though deer cause far more deaths annually.

Question 47

What is media bias in the context of audience engagement?

Answer 47

Media outlets tailor content to engage their primary audience by emphasizing stories that align with their viewers' interests, hopes, and fears, even if the stories are perfectly accurate.

Question 48

How do tailored news and social media feeds contribute to political polarization?

Answer 48

By reinforcing pre-existing views and amplifying outrage toward opposing perspectives, creating echo chambers that limit exposure to conflicting ideas.

Question 49

What is the echo chamber effect?

Answer 49

A situation where individuals are exposed only to information and opinions that reinforce their existing beliefs, preventing discovery of new or opposing perspectives.

Question 50

Why is "checking news from the other side" insufficient to combat media bias?

Answer 50

It fails to address the deeper issue of tailored content and confirmation bias, which require a more rigorous effort to engage with the best arguments from opposing views.

Question 51

What is publication bias in scientific research?

Answer 51

The tendency for journals to favor studies with surprising or engaging results, leading to underrepresentation of studies that confirm conventional wisdom.

Question 52

What is the file drawer effect?

Answer 52

The tendency for researchers to avoid publishing studies with negative or "boring" results, leaving valuable data unshared and amplifying publication bias.

Question 53

How does the file drawer effect impact the reliability of scientific evidence?

Answer 53

It skews the available evidence by excluding studies with negative results, potentially misleading researchers about the validity of a hypothesis.

Question 54

How does pre-registration help combat publication bias?

Answer 54

By requiring researchers to announce their study protocols in advance, ensuring that all results, even unpublished or incomplete ones, are accounted for in the data pool.

Question 55

What effect does media bias have on our perception of issue importance?

Answer 55

It magnifies certain issues that resonate with specific audiences while downplaying or ignoring others, skewing our sense of their actual prevalence or importance.

Question 56

How does social media exacerbate confirmation bias?

Answer 56

Algorithms prioritize content that aligns with user preferences, making it more likely for individuals to encounter and share information that confirms their existing beliefs.

Question 57

What problem arises when studies supporting surprising claims are published while others are not?

Answer 57

It creates a distorted view of the evidence, making the surprising claim appear more valid than it is.

Question 58

What is the role of engagement-focused algorithms in news consumption?

Answer 58

They prioritize content that generates likes, shares, or emotional reactions, often reinforcing biases and amplifying polarization.