Research Methods

Research Methods – True or False?

1. Human intuition is remarkably accurate and free from error. False

2. Most people seem to lack confidence in the accuracy of their beliefs.

False

3. Most people suffer from unrealistically low self-esteem. False

4. The opinions of 1500 randomly selected people can provide a very accurate picture of the opinions of an entire nation.

True

5. Research suggests that students spend more than 28% of their waking hours in conversation.

True

6. The scientific finding that depressed people tend to have low self-esteem proves that depression causes people to be down on themselves.

False7. The purpose of the experiment is to re-create behaviors exactly

as they occur in everyday life. False

8. Males and females exhibit similar overall intelligence and well-being.

True9. Under ethical and legal guidelines, animals used in experiments

rarely experience pain. True

10. As a science, psychology is objective and value-free. False

Let’s Make a Deal!

Correct Answer

Participants Choice

Stay/Switch Win/Lose

A B SWITCH WIN

• Calculate the percentage of wins from switching.• For example, if you switched a total of 10

times and won 7, your win rate would be 70%

• Calculate the percentage of wins from staying.• If you stayed 10 times and won 5 of those

times, your win rate would be 50%

I. Reasoning Fallacies

A.Hindsight bias1. Tendency to believe, after learning

an outcome, that one would have foreseen it

2. The “I knew it all along” phenomenon

3. Ex: After the Packers lost on Sunday, people thought, “I knew all along they’d lose.” – even if they didn’t

How long would it take you to figure out these word scrambles? wreat water etryn entry grabe barge

Unscramble this word: ochsa

B.Overconfidence1. Tendency to think we know

more than we do2. EX: Thinking you did better on a

quiz than you actually did

Examples of Overconfidence

“There is no reason for anyone to have a computer in their home.” ~Ken Olson, president of Digital Equipment Company, 1977

“Heavier-than-air flying machines are impossible.” ~Lord Kelvin, British mathematician, 1895

“Man will never reach the moon, regardless of all future scientific advances.” ~Lee Deforest, inventor of the vacuum tube, 1957

“Nuclear powered vacuum cleaners will probably be a reality within 10 years.”~Alex Lewyt, manufacturer of vacuum cleaners, 1955

Astrology

E = Aries (March 21 – April 19)

B = Taurus (April 20 – May 20)

C = Gemini (May 21 – June 21)

A = Cancer (June 22 – July 22)

F = Leo (July 23 – Aug 22)

D = Virgo (Aug 23 – Sept 22)

K = Libra (Sept 23 – Oct 22)

H = Scorpio (Oct 23 – Nov 21)

I = Sagittarius (Nov 22 – Dec 21)

L = Capricorn (Dec 22 – Jan 19)

J = Aquarius (Jan 20 – Feb 18)

G = Pisces (Feb 19 – March 20)

II. Ethics

A. In conducting an experiment, psychologists must

1. Obtain informed consent of participants

2. Protect them from harm and discomfort

3. Treat info about participants confidentially

4. Fully explain research afterward

III. Testing hypotheses with descriptive methods

A. Case study - studies one person in depth in hopes of revealing universal principles

EX: studying a patient with a specific mental disorder

B. Survey - uses a representative sample of people to estimate attitudes or reported behaviors of a whole population

1. Population - all the cases in a group being studied from which samples may be drawn

2. Random sample - every member of a population has an equal chance of inclusion

A Random Sample

Random Sampling

At the end of the first two weeks of the baseball season, newspapers start publishing the top ten batting averages. The leader after the first two weeks normally has a batting average of .450 or higher. Yet no major league baseball player has ever finished the season with a better than .450 average. What do you think is the explanation for the fact that batting averages are higher earlier in the season?

Importance of Sample Size

Imagine you are a golfer of above-average ability and that you have the opportunity to play the greatest golfer in the world. If you want to maximize your slim chance of winning, how much golf would you elect toplay, g iven the choices of 1, 18, 36 or 72 holes?

A certain town is served by two hospitals. In the larger hospital about 45 babies are born each day, and in the smaller hospital about 15 babies are born each day. Although the overall proportion of boys is about 50%, the actual proportion at either hospital may be greater or less than 50% on any day. At the end of a year, which hospital will have the greater number of days on which more than 60% of the babies born were boys?a. The larger hospital

b. The smaller hospital

c. Neither – the number of days will be about the same (within 5% of each other)

Examples of Poorly Worded Questions

“Does Michigan spend too much, too little or the right amount on prisons and corrections?” 38.4% said too much; 35.4% said not enough When asked whether spending $1.3 billion on prisons and

corrections was too much, too little or the right amount, 54.9% said too much, 14% said not enough

American Museum of Natural History survey found: 77% of people were interested in plants and trees but only

39% were interested in botany 48% were interested in fossils but only 39% were

interested in paleontology 42% were interested in rocks and minerals, but 53%were

interested in geology

“The problems faced by Blacks were brought on by Blacks themselves.” When interviewed by Whites, 62% of White

respondents agreed When interviewed by Blacks, 46% agreed

When a New York Times/CBS News poll asked people if the favored an amendment “prohibiting abortions”, a majority opposed it When asked whether they favored “protecting

the life of the unborn child,” 20% switched sides

The worst poll question of all time (1937 British Gallup Poll question): “Are you in favor of direct retaliatory measures

against Franco’s piracy?” Problems:

It is not balanced. It assumes knowledge. It does not use every day language. It employs a pejorative (a word/phrase that has

negative connotation). It is vague.

C. Naturalistic observation - observing and recording behavior in a natural environment

1. Studying gorillas in the wild or high school behavior in the lunch room

2. Advantage: Can observe someone in his natural environment

3. Disadvantages: 1. Reactivity subject’s behavior is different when

the person knows he is being observed than it would otherwise be

2. Single cases may be misleading

D.Correlational studies1. Measure how closely two things vary

together and thus how well either one predicts the other

2. Graphed on a scatterplot and measured with a correlation coefficient

a. Positive = two sets of scores rise or fall together

b. Negative = two sets of scores relate inversely

c. zero = weak correlation

3. CORRELATION DOES NOT PROVE CAUSATION

EX: Self-esteem and depression are negatively correlated. Which is causation? Is a third factor (heredity, age) to blame?

Examples

“People who floss their teeth more often live longer.”

“The number of drownings in the U.S. rises and falls during the year, along with the amount of ice cream sold each month.”

People who often ate Frosted Flakes as children had half the cancer rate of those who never ate the cereal. Conversely, those who often ate oatmeal as children were four times more likely to develop cancer than those who did not.

4. Illusory correlation: The perception of a relationship where none exists

EX: It always rains after you wash your car.

Consider a random coin flip…

If someone flipped a coin six times, which of the following sequences of heads (H) and tails (T) would be most likely?1. HHHTTT

2. HTTHTH

3. HHHHHH

Correlation examples - which are positive and which are

negative?

The more your children watch TV, the less they read. Negative correlation

The more sexual content teens see on TV, the more likely they are to have sex. Positive correlation

The longer children are breast-fed, the greater their later academic achievement. Positive correlation

The more often adolescents eat breakfast, the lower their body mass. Negative correlation

Blue Brown Green Orange

Red Yellow

Predicted %

Observed Frequency

Actual

24% 13% 16% 20% 13% 14%

E. Experimentation: in psychology, a study where variables are manipulated to determine a casual outcome

1. Random assignment - assigning participants to experimental and control groups by chance

2. Double blind procedure - neither the research participants nor the research staff know whether participants have received the treatment or a placebo

3. Placebo effect - experimental results caused by expectations alone• EX: A drug/treatment works simply

because the participant believes it will

EXPERIMENTAL EXAMPLE

F. Experimental terms using the hypothesis: Breast feeding increases intelligence

1. Experimental group - group exposed to treatment Babies who are breastfed

2. Control group - group not exposed to treatment Babies who are bottle fed

3. Independent variable (IV) - experimental factor that is manipulatedBreast fed or bottle fed

4. Confounding variable - factor other than the IV that might produce an effect in an experimentEnvironment, diet, wealth

5. Dependent variable - outcome factor; variable that may change in response to manipulations of the IVIntelligence

6. Statistical significance - observed difference is likely not due to chance variation between the samples

Practice

Experiment: To test the effect of perceived ethnicity on the availability of a rental house, Adrian Carpusor and William Loges (2006) sent identically worded e-mail inquiries to 1115 Los Angeles-area landlords. The researchers varied the ethnic connotation of the sender’s name and tracked the percentage of positive replies. “Patrick McDougall,” “Said Al-Rahman,” and “Tyrell Jackson” received, respectively, 89%, 66% and 56% invitations. What is the independent variable?

Ethnicity related names What is the dependent variable?

Positive response rate

How could these proverbs be tested?

It takes four hours to come down from your last cup of coffee.

Wearing dark clothes on the bottom and light clothes on the top is usually more visually appealing than the reverse.

As family income rises, the ratio of women’s shoes to men’s shoes increases accordingly.

Don’t change your first guess on a multiple choice test.