FINDING AND USING EVIDENCE

Types of Evidence

The Research Process

Documentation

TYPES OF EVIDENCE

EVIDENCE OF FACT INCLUDES;

ARTIFACTS - Objects of proof

FIGURES & STATISTICS - Numbers

SPECIFIC EXAMPLES - Stories

TYPES OF EVIDENCE

• EVIDENCE OF OPINION (Quotations):

PERSONAL TESTIMONY - A story like anexample, but told in the first person. Also,“person in the street” type of opinions.

EXPERT TESTIMONY - Quotations fromfrom specially qualified people.

ARTIFACTS

• AN ARCHEOLOGICAL OBJECT, LIKE A

SKULL OR OLD POTTERY.• IN A SPEECH, MODELS, MAPS, AND

SAMPLES OF VARIOUS KINDS • FINGERPRINTS, FOOTPRINTS, DNA,

AND OTHER PROOFS ACCEPTED IN A

COURT OF LAW.

FIGURES AND STATISTICS

• A FIGURE IS A COUNTED NUMBER.

THEY’RE VERIFIABLE FACTS THAT

CAN BE VERIFIED BY A CENSUS.

• A STATISTIC IS A NUMBER APPLIED

ACROSS A SAMPLE POPULATION TO

ACHIEVE AN AVERAGE.

EXAMPLE

For the first time in history, the number of inmates in American prisons and jails has exceeded 2 million. These numbers continue to rise at 2.3% a year, or 900 inmates each week according to government sources. Recent surveys from the US Department of Justice show that 55% of the current population is incarcerated for a drug related offense. With the costs for the Federal Government annually into the hundreds of billions; there are billions alone spent on drug offenders.

EXAMPLE

• The U.S. now has one of the highest per capita incarceration rates in the world, rivaling that of Russia. Our incarceration rate is more than four times that of Canada, five times that of Britain, and 14 times that of Japan according to the USDJ, Bureau of Justice Statistics. 

SPECIFIC EXAMPLES

• STORIES THAT ADD A HUMAN FACE• SHOW THE QUALITY OF A PROBLEM• THEY SHOULD BE VERIFIABLE, NOTRUMOR OR “FISHING STORIES.”• HELP US TO IDENTIFY WITH PEOPLEINVOLVED WITH A PROBLEM.

Aristotle: “Pity and Fear for one like ourselves.”

Civilian Iraqi Death

• “They just shot my brother dead, for no reason,’ Kudair exclaimed. As several witnesses attested, Yaass had been unarmed. ‘He was not a resistance fighter but a simple civilian who worked hard to feed his family." Had the Americans offered any explanation for the killing? ‘Of course not. We don't even exist for them. They have not liberated us, not us.’” He was shot for a curfew violation.

• Kleveman, Lutz. “America’s War on Terrorism has Provoked International Resentment.” 2005.

Schools

• "Narrowing the curriculum has clearly become a nationwide pattern," said Jack Jennings, the president of the center, which is based in Washington. At Martin Luther King Junior High School in Sacramento, about 150 of the school's 885 students spend five of their six class periods on math, reading and gym, leaving only one 55-minute period for all other subjects.

Personal Testimony Example

• Here’s mine as a three time kidney transplant. I’m not a doctor, but I’m a guy affected by the issue:

• Get your blood pressure checked regularly. It is truly the silent killer. I was running and working out regularly and thought I was in good shape.

Yet my kidneys failed by my age of 33. If only I’d checked my blood pressure before it was too late.

Medicare Prescriptions

• Many beneficiaries say they are grateful to local insurance counselors, rather than to Medicare, the government or politicians."We had a whole lot better deal before the government started messing with it," said Francis A. Murphy, 79, a retired airline mechanic who is losing drug benefits from a former employer. He said he did not expect to see any savings under Medicare.

EXPERT TESTIMONY

Let’s try several examples on a single topic

but put them into Toulmin Argument Form.

Let’s discuss benefits of coffee (besides

helping you to finish this course).

COFFEE

• Claim: Coffee is rich in antioxidants• Ground 1: Walter Willett, chairmen of the department

of nutrition at Harvard School of Public Health and a leading investigator of coffee points out that like tea, coffee is rich in antioxidants

• Ground 2: According to Joe Vinson, a chemistry Professor at the University of Scranton in Pennsylvania, coffee topped the list of food that are densest in antioxidants, surpassing blueberries, broccoli and other produce. Only chocolate, dried fruits, and dried beans ranked higher.

COFFEE

• Claim: Coffee in moderation is good for you.• Warrant: Doctors say coffee contributes to the

prevention of many ailments.• Grounds 1: Doctors quoted in Better Homes &

Garden, August 2003 issue, states that diseases that coffee may help prevent are cirrhosis of the liver by 80%, Parkinson’s disease by 50% to as much as 80%, colon cancer by 25% and gallstones by 4%.

(CONT.)

COFFEE

GROUNDS 2: According to the December 19, 2005 issue of U.S. News & World Report - Health & Medicine:

• Potassium, niacin, magnesium, and chlorgenic acids are just some of the nutrients in coffee that scientists suspect may counter the risk of diabetes.

• American, Finnish, and Swedish studies all suggest that both decaffeinated and regular coffee reduce the risk of type 2 diabetes.

• Coffee has been linked to lower incidence of bladder cancer in heavy smokers. (CONT.)

COFFEE

• Ground 3: Researchers at the National Institute of Diabetes and Digestive and Kidney Disease found that a two-cup-a-day habit can dramatically cut the risk of chronic liver disease.

IN SUM

* EVIDENCE IS OF TWO TYPES: OFFACT AND OF OPINION.

* FACTS INCLUDE: ARTIFACTS, STATS,FIGURES, AND SPECIFIC EXAMPLES.

* OPINIONS INCLUDE: PERSONAL TESTIMONY AND EXPERT TESTIMONY.

CREDIBILITY

• PERSONAL QUALITIES AND BEHAVIORS THAT MAKE SOME SOURCES AND SPEAKERS MORE BELIEVABLE THAN OTHERS.

• ARISTOTLE CALLED THIS “ETHOS”

• HE, CICERO AND OTHERS NAMED

SPECIFIC FACTORS:

CREDIBILITY FACTORS

• Attractiveness, in the sense of clothing, personality, and personal features

• Believability, appearing to be sincere

• Competence, the ability to perform tasks well

CREDIBILITY FACTORS

• Consistency, some sense of integrity among the person’s messages

• Dynamism, the ability to excite and activate• Good Will, having a sense of what’s best for the

people and a wish to give it

• Honesty, which is not the same thing as the appearance of same

CREDIBILITY FACTORS

• Moral Character, including criminal record or sexual indiscretions

• Knowledge, both in the sense of study and experience

• Wisdom, which is the ability of someone to use knowledge well

TESTS OF EVIDENCE

• NOT ALL EVIDENCE IS EQUAL.

• SOME EVIDENCE COMES FROM MORE CREDIBLE SOURCES.

• SOME EVIDENCE HAS BEEN DISTORTED OR HAS BIAS.

• SOME PUBLICATIONS HAVE BETTER REPUTATIONS THAN OTHERS.

TESTS

• Accuracy: Begin by directly quoting evidence, rather than paraphrasing it in any subjective sense. Anyone can be tempted to include or leave out details that emphasize one’s own point of view.

TESTS

• Relevancy: Make sure the evidence clearly relates to the claim.

• If your topic focus is within American borders, evidence about Europe wouldn’t work for you.

• This is as much a part of your properly phrasing the claim as it is finding the right evidence.

• •

TESTS

• Sufficiency: Does the evidence prove the full extent of the claim?

• Does it meet your burden of proof?• A common novice error is to exaggerate the impact of the available evidence.

• Your claim should say no more than you can prove.

TESTS

• Verifiability: Can you confirm your findings with more than one source?

• Does the field of opinion show some coherent point of view?

• Are you basing your claim on an exceptional case or a single eccentric perspective?

TESTS

• Recency: Do you have the most current information about your topic?

• Being updated by an opponent, when you had access to the same information, is awkward.

TESTS

• SOURCE-BASED EVIDENCE NEEDS SOME ADDITIONAL TESTS:– EXPERT QUALIFICATIONS?– POSSIBLE BIAS?– FIRSTHAND WITNESS?– CONSISTENT? (YOU’LL BE EVALUATED FOR THATYOURSELVES.)

TESTS

• STATISTICS REQUIRE THESE TESTS:Are the figures upon the statistics are

based accurate?Are the statistics based upon a

representative sample?Are the methods appropriate to justify

the stat?

APPEALS

* PATHOS appeals to an audience’s sense of emotion, as in the case

of the word “pathetic.”

* LOGOS appeals to an audience’s sense of logic and reason.

* ETHOS is the appeal of a credible

speaker. “Ethos of the person.”

EVIDENCE AND APPEALS

ANY EVIDENCE BIT MAY HAVE THE

FORCE OF ANY APPEAL, BUT CERTAIN

NATURAL RELATIONSHIPS EXIST:

*FOR LOGOS USE NUMBERS

*FOR PATHOS USE STORIES

*FOR ETHOS, ASSOCIATE WITH THE BEST AND BRIGHTEST SOURCES

EVIDENCE & PERSUASION

RESEARCH INDICATES THAT:

• Documented testimony is consistently persuasive.

• Statistics are strengthened when combined with examples.

• Novel information is more persuasive than familiar information.

EVIDENCE & PERSUASION

• Evidence seems to inoculate audiences against future counter-argument.

• Evidence that reinforces audience belief is more persuasive than that challenges it. • Evidence consistently increases speaker

credibility.• It’s most effective with educated audiences

interested in the facts.

RESEARCH

• GO TO THE CLASS TOPICS LINKS FOR HELP FINDING A SUBJECT.

• RESEARCH YOUR PROP. OF FACT.• FIND AT LEAST THREE PIECES OF

EVIDENCE.• BUILD SOME BASIC ARGUMENTS

WITH CLAIMS AND GROUNDS.