SAT R&W 6: Command of Evidence

Evidence

Information that supports or undermines a proposition or claim. The strength of the evidential connection can range from weak correlation to very strong proof.

What makes evidence relevant to a claim?

Relevant evidence bears directly on the claim or on a prediction that distinguishes it from alternatives. Information may be true and related to the topic without actually supporting the specific claim at issue.

How can a reader locate textual evidence for a claim?

First identify the exact claim being evaluated, then find the sentence, example, explanation, or detail that directly supports, contradicts, or qualifies it. The best evidence has a clear logical connection to the claim.

What makes one piece of evidence stronger than another?

Stronger evidence is more directly relevant, reliable, specific, and difficult to explain through competing interpretations. Evidence that merely correlates with a claim is generally weaker than evidence tied to a distinctive prediction of that claim.

How can evidence support one explanation over another?

Evidence is especially useful when competing explanations make different predictions. An observation that agrees with one explanation but conflicts with another provides stronger grounds for favoring the first.

Confirmation and disconfirmation

Confirmation occurs when evidence agrees with a claim's predictions; disconfirmation occurs when evidence conflicts with them. Neither term necessarily means that a claim has been proved or disproved absolutely.

What does the probabilistic view of evidence assert?

Evidence $E$ supports hypothesis $H$ when observing $E$ increases the probability of $H$: $P(H\mid E)>P(H)$. Thus, evidence can increase confidence without making the hypothesis certain.

Why can agreement between evidence and a claim fail to prove the claim?

Different claims can sometimes predict the same result, especially when evidence is limited. Agreement increases support, but competing explanations must also be considered.

What is the problem of underdetermination?

Underdetermination occurs when the available evidence is consistent with two or more competing claims or explanations. Additional evidence may be needed to distinguish among them.

Why is anecdotal evidence generally weaker than systematically collected evidence?

Anecdotes may be affected by uncontrolled variables, selective reporting, measurement error, or personal bias. Systematic methods make the evidence more reliable by using defined procedures and broader or repeated observations.

What is the difference between evidence and proof?

Evidence supports or challenges a claim, often with some degree of uncertainty. Proof establishes a conclusion decisively; in many empirical contexts, conclusions remain revisable rather than absolutely proved.

What is theory-ladenness of evidence?

Theory-ladenness is the idea that observations and measurements may depend on background assumptions or interpretations. The same data may therefore be understood differently when readers disagree about how it was produced or what it represents.

How should contradictory evidence be evaluated?

Examine the reliability and relevance of the evidence, the method used to obtain it, possible errors or uncontrolled factors, and whether the result is reproducible. A contradiction should not automatically settle the issue without evaluating these conditions.

How should quantitative evidence from a table or graph be evaluated?

Identify the variables, units, scale, and comparison being made. Then determine the relevant trend, difference, ratio, or exception rather than relying on a general visual impression.

How can a table or graph support a textual claim?

The data support the claim when the relevant values or trend agree with what the text asserts. The support is strongest when the data directly measure the claim and the comparison uses the correct categories, units, and time period.

How can quantitative evidence qualify or weaken a textual claim?

Data can show that a claim is true only under certain conditions, less extensive than stated, or contradicted by an important exception. A careful answer should reflect the specific pattern in the data rather than overgeneralize.

What should a reader do when text and data appear to conflict?

Check whether the text and data refer to the same population, variables, units, and time frame. If they do, use the data to identify whether the text's claim is contradicted, limited, or based on a different comparison.

What is the difference between qualitative and quantitative evidence?

Qualitative evidence describes characteristics or observations, such as color change or the presence of a feature. Quantitative evidence consists of numerical measurements, such as percentages, rates, amounts, or temperature values.

How do repeated measurements strengthen evidence?

Repeated measurements help reveal random variation and increase confidence in the observed result, often through statistical summaries such as an average. Repetition does not automatically eliminate systematic error or prove a claim.

What is the burden of proof?

The burden of proof is the responsibility of the person making a contentious claim to provide sufficient evidence for it. The amount and quality of evidence required depend on how strong or consequential the claim is.

Why must evidence be public and verifiable when competing claims are being compared?

Evidence that others can inspect and verify allows readers or researchers to evaluate the same information rather than relying on a private impression. This makes comparison of competing claims more objective.