Presentation on theme: "1. Personal Observation 2. Case Studies 3. Research Studies 4. Analogies CO SCI 58 Chapter 9 Evidence."— Presentation transcript:
1. Personal Observation 2. Case Studies 3. Research Studies 4. Analogies CO SCI 58 Chapter 9 Evidence
1. Personal Observation We value eyewitness testimony as evidence. Problems: See or hear what we wish to Remember aspects of an experience that are most consistent with our background What we see or hear is filtered through our values, attitudes and expectations.
Eyewitnesses to the Sniper? Even the expectation of a composite sketch—based on accounts from eyewitnesses to Monday's shooting outside a Fairfax County, Virginia, Home Depot—came to nothing. "Because of darkness and distance and perhaps excitement and adrenaline at the time, we are unable to come up with a composite," said Montgomery County police Capt. Nancy Demme.said As The Washington Post and other sources noted, the witnesses gave "vague and inconsistent accounts," disagreeing on virtually all details other than the sex of the apparent shooter. All the witnesses agreed they'd seen a man, but some reportedly described a with "with dark skin, others with olive complexion, of Middle Eastern appearance or Hispanic"; one apparently said he was "not white, not black." Such imprecision is mirrored in the descriptions of the killer's (or killers') vehicle, which has been variously described a white Chevy Astrovan, a Ford Econoliner, and a white panel truck. Gillespie, Nick. “Shooting Blind.” Reason Online.” 17 Oct (6 Nov. 2002)
Eyewitness Testimony Wrongfully Imprisoned At the age of 39, James Newsome walked out of a maximum- security prison in Illinois after 15 years of wrongful incarceration. Newsome was convicted and sentenced to life in prison after three witnesses identified him as the man who shot and killed a 72- year-old grocery store owner on the South Side of Chicago, even though his fingerprints didn’t match those at the scene. But in 1994, fingerprint technology proved the real perpetrator was a man on death row. Newsome was given a settlement of $140,000 by the state, but he didn’t think that was enough of an apology. Now he’s suing the police officers and the Chicago Police Department for millions for gross misconduct. Sinatra, Amy. “It’s Him – Or Is It?” ABCnews.com.” y.html (6 Nov. 2002) y.html
2. Case Studies The study of a particular individual or event. Based on observations or interviews May be very systematic or superficial Vivid case studies should be viewed as striking examples rather than as proof.
Evaluating Case Studies Demonstrates that an outcome is possible. Ask Is it typical? Are there counterexamples? Are there biases in how it’s reported? Asians are so good at math; there are four of them in my algebra class and they have the top scores. Men are terrible cooks-both my brother and my boyfriend have burned dinners this year.
Through the Looking Glass: Student Perceptions of Online Learning I logged on to my computer one Sunday evening to find myself immediately greeted by an instant message from a 17-year-old student in one of my courses. The message was simple: "Help!" As I later learned, the student had encountered difficulty in conducting Internet research for a class project. She said she felt like Alice in Wonderland, having fallen through the looking glass. A computer novice, she was relieved to find me online that night and was able to finish her assignment. This is one example of the effect of computers and the Internet on students' learning experiences. As distance education becomes more popular, and as traditional courses require more online assignments, teachers must consider students' perceptions of online learning. While many professors and teachers embrace this technology, many students experience confusion and frustration. By Linda Peters
Through the Looking Glass: Student Perceptions of Online Learning Linda Peters provides the case of a 17 year old student who felt frustrated trying to complete an assignment to prove that teachers must consider students’ perceptions of online learning. You need to ask: Is this typical? Are there counterexamples? I have students who take every online course I offer. Some have taken almost every online course that is available at the college. They must not feel too frustrated and would make good counterexamples. Maybe this instructor arranged her class and instructions poorly. I was also not impressed by this student using the single word message of Help! As an instructor, that frustrates me. I don’t know where to start to assist and sometimes I have hundreds of online students. It is more effective for a student to ask a question like: “Can you help me understand the Excel formula for step 3?”
3. Research Studies A systematic collection of observations by people trained to do scientific research. This kind of evidence CAN BE very dependable, but the research must use the scientific method. Studies show that violent computer games cause aggressive behavior in children. Or do they? A recent report indicates that female college students are intimidated by computer classes.
Scientific Method Publicly verifiable data The data must be obtained under conditions such that other qualified people can make similar observations and obtain the same results. Precision in Language. The language must be precise and consistent.
NOT Verified In 1986, scientists reported that extremely gifted 12- and 13-year-olds were especially likely to be left-handed and to suffer from allergies. They proposed that the kids, while in the womb, had been overexposed to testosterone, which might have triggered both the allergies and the intellectual excellence. But this exotic idea vaporized in the summer of 1990 when different researchers-Jennifer Wiley and David Goldstein of Duke University-did a follow-up study; they found no evidence of a link between giftedness and left-handedness and allergies in children. From Diestler, Sherry. Becoming a Critical Thinker p. 144
Scientific Method: Control Minimizing extraneous factors that might affect the accuracy and interpretation. Use multiple observers Do in a controlled environment like a lab Hard to apply in studies of the social world and human behavior. People may behave differently when they know they’re being watched.
Evaluating Research #1 What is the quality of the source? Most dependable are journals where the study is reviewed by a panel of experts, like the Journal of the American Medical Association. Has the study been replicated? Have other studies shown consistent results? Are conditions in the research artificial? How similar are the conditions under which the research study was conducted to the situation the researcher is generalizing about?
Evaluating Research #2 Is there a reason for someone to have distorted the research? Money, position, prestige.. Has the study been selectively chosen? Are there studies with contradictory results that were not mentioned? How far can we generalize, given the research sample?
At a Lecture-Only 12% Listen Bright-eyed college students in lecture halls aren’t necessarily listening to the professor, the American Psychological Association was told yesterday. If you shot off a gun a sporadic intervals and asked the students to encode their thoughts and moods at that moment, you would discover that: About 20% of the students, men and women, are pursuing erotic thoughts. Another 20% are reminiscing about something. Only 20% are actually paying attention to the lecture. 12% are actively listening. The others are worrying, daydreaming, thinking about lunch or-surprise-religion (8%)
Continued.. This confirmation of the lecturer’s worst fears was reported by Paul Cameron, 28, an assistant professor at Wayne State University in Detroit. The annual convention, which ends Tuesday, includes about 2,000 such reports to 10,000 psychologists in a variety of meetings. Cameron’s results were based on a nine-week course in introductory psychology for 85 college sophomores. A gun was fired 21 times at random intervals, usually when Cameron was in the middle of a sentence. (Diestler, p. 113)
Evaluation Has the study been replicated? None stated Are conditions in the research artificial? Is firing a gun to interrupt lectures normal? How far can we generalize given the research sample? A single 9 week introductory course with 85 students with one particular teacher. Are there any biases or distortions in the surveys, questionnaires, ratings, or other measurements? Unknown, the data collection method was not described.
Distortion? The first head-to-head comparison of the nation’s two most popular medicines for prostate trouble found that one gives significant relief while the other is virtually useless. The two medicines, Hytrin and Proscar, are taken by millions of older men to relieve the symptoms of an enlarged prostate gland. The study found that Hytrin eases men’s discomfort by about one- third, while Proscar works no better than dummy sugar pills. Prostate drugs generally cost $30 to $45 a month. The study was financed by Merck & Co., which makes Proscar, and Abbott Laboratories Inc., the maker of Hytrin. Although both companies approved the study’s design, Merck discounted its significance as publication approached in today’s issue of the New England Journal of Medicine. Dr. Glenn Gormley, a Merck research official, said that in hindsight, the study was not set up properly to answer the question of which drug is better. (Diestler, p. 146 )
Generalizing Based on a Sample The sample must be: Large enough to justify the conclusion. Usually the more events or people observed, the better. Possess as much diversity (breadth) as the types of events about which conclusions are drawn. As random as possible to prevent getting groups of people that have biased characteristics.
Hasty Generalization Fallacy Generalizing from a limited number of cases. From the Daily Breeze Letter of the Day: Tickets encourage good behavior In Manhattan Beach on Marine Avenue, instead of going to the light by Tomboy’s, many people – including myself – turned left over the double lines to get into Costco. After seeing two people get tickets, I notice everyone, including me, now goes to the light, even if it takes two minutes longer. Until the police gave the tickets no one was motivated.
What’s wrong with this sample? In Pennsylvania, where liquor can’t be sold on Sunday, 2,000 people were interviewed at a beer festival; 96% of those surveyed believed that the Sunday ban on liquor sale is outdated. Clearly, Philadelphians (where the festival was held) disapprove of the law, commonly called a Blue Law.
Surveys & Questionnaires The survey has to be answered truthfully. People often give answers they think they’re supposed to give. Questions may be ambiguously worded. The wording of the question may be biased. Answers can vary based on the position of the question in the survey and how the survey is presented. Previous slide answer: Those surveyed were attending a beer festival
Conclusion and Question Here’s a conclusion based on a survey: A U.S. congressman sent a questionnaire to his constituents and received the following results: 92% were against government-supported child-care centers. The question that was asked: Do you believe the federal government should provide child-care centers to assist parents in rearing their children? (Textbook page 135)
Flaws in the Survey Leading words: to assist parents in rearing their children What if you substitute: to assist parents who are unable to find alternative child care while they are working? Could you generalize these results to all parents in the U.S.? Maybe there is a bias to people who return surveys from their politicians.
4. Analogies as Evidence Proving a conclusion about something unfamiliar by relying on similarity to something more familiar or that is easier to study. A researcher may report that when rats are confined to an overcrowded cage, they exhibit antisocial behavior; a conclusion is then drawn about humans, comparing crowded rats to city dwellers. The researcher may imply that crime is a result of overcrowded conditions. (Diestler, p. 169)
Faulty Analogy Fallacy There are significant differences between the two things being compared. Scott Adams Dilbert strip 10/14/02
Evaluating Analogies 1. The number of ways the two things being compared are similar. 2. The relevance of the similarities and the differences. 3. Try to generate your own alternative analogies to better understand. End of Chapter 9 Lecture