Chapter 2: Conducting Research

Psychology is an experimental science. Theories of behavior must be supported by evidence.

5 Steps of Scientific Research

• Form a Question• Form a Hypothesis• Test the Hypothesis• Analyze the Results of the Test• Draw Conclusions

Form a Question

• Do people learn by observing others?• Do people learn better in small groups or alone?• Do clients prefer counselor self-disclosure?• Do older children (birth order) do better in school?• Are the babies of the family spoiled?QUESTION MUST BE MEASUREABLE!Are athletes nicer, prettier? (How do you measure this?)

Form a Hypothesis

• Make an educated guess• A child who watches Power Rangers will be more aggressive• A child who plays Medal of Honor will most likely go into the military• Students who sit in the front of the class get better grades• Kids will buy the candy closest to them at the camp store window• Grandpa’s and Grandma’s drive slower

Test the Hypothesis

• CAREFULLY EXAMINE THE BEHAVIOR IN A NATURAL OR CONTROLLED ENVIRONMENT• Decide what information is needed to test the hypothesis (What is the

best way to gather information?)• If you want to see if fat people eat bad foods, survey their carts at the grocery

store before checkout• If you want to see if skinny people eat slower, observe them in a café• Survey questions DO NOT always work…people often tell you what they think

you want to hear

Test the Hypothesis Continued

•GATHER THE INFORMATION: This could take weeks, months, or even YEARS•Conduct a survey• Take a survey•Observations

Analyze the Results of the Test

• SUMMARIZE THE DATA STATISTICALLY• Look for patterns and relationships in the data•Use complex statistical tests to see if results are

better than chance

Draw Conclusions

•DID THE OBSERVATIONS SUPPORT THE HYPOTHESIS?•Were there predicted results?•Were there unpredicted results?•Do you have any predictions for future results?•How can you adjust or refine the original

hypothesis?

Replication•For findings to be confirmed, they must be REPLICATED with a different sample of subjects or else results may be a random occurrence.• If you repeat your findings with different people (gender,

socioeconomic status, age, education, geographic region) and get similar results, your findings are more robust.

New Questions

•Perhaps your research methods will lead you to formulate new hypothesis tests, methods of information gathering, and results for further discussion.

Research Methods: Selecting Samples• Important to carefully consider what group of people

you will examine (ex: if you are interested in behaviors in the parking lot…don’t ask freshmen)• To accurately predict an outcome, your sample must

be representative of the target population.

Selecting Samples: Two Ways• Random Sample• Individuals are selected by chance from the target population• Everyone has an equal chance of being chosen• If it is big enough, it will accurately represent the entire target population

• Stratified Sample• Subgroups in target population are represented proportionally• U.S. by race

• 74% non-Hispanic white• 10% Eskimo / Native Americans• 3% Asian• 10% Hispanic• 12% African American

• U.S. by sex, by grade, by age, by race…you can’t always account for all these• The bigger your sample, the more likely it will be stratified

Selecting Samples• Generalizing Results: researchers are careful not to generalize their

findings to groups not represented in their sample• Can be bias because of gender, race, geographic location,

socioeconomic status or volunteer bias• People who volunteer to participate in research studies often differ

from people who do not• More willing to disclose personal information• More interested in research• More spare time

• People who complete magazine studies• Read magazines• Have time to fill out the surveys• Different leisure preferences

Survey Method• Gathering information by asking people directly• Through a questionnaire• Through interviews in person or over the phone or e-mail

• Advantages• Questionnaire – people can be more anonymous• Interviews – more likely to do it and not throw it away

• Issues of confidentiality or honesty in all methods• People will sometimes say what they think you want to

hear• People may not always tell the truth• People are not always comfortable sharing their thoughts

Methods of Observation

• Learn a lot from watching people• Psychologists use careful methods of observation to investigate

behavior

Testing Method

• Psychologists use tests (I.Q. tests, personality tests, aptitude tests, vocational tests, etc.)• Give us information about the persons (learning ability, temperament,

character, special skills, career interests, etc.)

Case Study Method• In depth investigation of an individual or small group• Use what they learn to generalize to a larger population• EX: Genie at 20 months was locked in a small room by her dad until 13. Mom

fed her, Dad beat her, no one spoke to her. She herself did not say a word. She eventually learned language, but not as well as most people. Case study conclusion: the critical period for language development is between 20 months and 13 years.

• Problems with case studies:• Difficult to REPLICATE• Often biased with interview format

• People don’t always remember• Some people distort the past• Researchers subtly bias respondents to answer how they want to hear

Longitudinal Method

• Looks at how people change over time (often years or decades)• Information collected at intervals• Tend to take long, be expensive, risky – no guarantee that people will

want to continue to participate

Cross-Sectional Method

• Includes and compares different people of different ages• Less reliable than longitudinal• Cannot be certain that age alone is responsible for differences in

behavior

Naturalistic Observation

• Observe people in actual environment• Homes• Schools• Offices• restaurants

• Do not interfere with the organism while observing• EX: people’s eating habits, grocery store carts, fast-slow chewers

Laboratory Observation Method

• Observe people and animals in a laboratory setting (more often animals)• Can sometimes control variables in a lab setting (does light or noise

influence behavior?)• TV Violence: observe kids’ behavior after watching a violent TV show

Analyzing Observations

•Correlations•How closely is one thing related to another?

• The stronger the correlation, the more likely they are to be related• Ex: Tall = basketball player• EX: Talk = teacher

Correlations

•Positive Correlation: as one goes up, so does the other• EX: Education and salary; height and basketball

player; money and happiness (?)•Negative Correlation: as one goes up the other goes

down• EX: stress and health; age and height; involvement

in extracurricular activities and grades (?)

Correlations

•Correlations are limited. They describe the relationship but they do not reveal cause and effect. One thing does not necessarily cause the other.

Experimental Method

• Used to establish cause and effect in research.• One group of subjects gets treatment (experimental group)• One group of subjects does not get treatment (control group)• Randomly assign subjects to each group. Assume other differencs

balance out with randomization• Behavior is observed or measured• All other conditions are held constant• If different – cause = treatment

Variables• Independent Variable: factor that researchers manipulate so that they

can determine its effect• Dependent Variable: behavior being measured or thought to be

influenced by independent variable• Example: Hypothesis: Children watching violent TV are more likely to

be violent• Independent Variables• Power Rangers TV show, Barney TV show (Experimental

Groups)• No TV show (control group)

• Dependent Variable: behavior after watching the show

Variables

• EX: Hypothesis: Review helps students perform better on tests• Class 1 gets a review game before a test• Class 2 does not get a review game before the test• Independent variable = review game• Dependent Variable = test scores

Placebo Effect

• Substance or treatment that has no effect apart from a person’s belief in it•Doctors find this to be true with certain hypochondria

patients and medication

Blind Studies

• Single Blind Study: participants unaware of whether they are receiving treatment or a placebo•Double Blind Study: participants and researchers are

unaware of who is in which group. Researchers remain less bias.

Experimental Method

• Advantages: researchers are able to manipulate variables to determine cause and effect. Laboratory setting enables researchers to monitor and record all stages of the experiment.• Disadvantages: conditions created in the lab may not accurately

reflect the conditions of real life. Experiments may be subject to volunteer bias, researcher bias and the placebo effect.

Ethical Issues

•Ethics: standards for proper and responsible behavior. Psychologists promote dignity of the individual, foster human welfare, maintain scientific integrity.•Psychological research should NOT be harmful

(consider the experimentation in Nazi concentration camps)•Animal experimentation: need to present all findings

(controversial)

Confidentiality and Informed Consent• Information is private (subjects more likely to disclose

true information and feelings)•People agree to participate in a research study after

they know what its about and choose to participate•Deception can only take place if the potential benefits

outweigh the potential harm•When the participants receive an explanation of the

study after it occurred.