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

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

• 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?)

• 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

• 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

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

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

• 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?

• If you repeat your findings with different people (gender, socioeconomic status, age, education, geographic region) and get similar results, your findings are more robust.

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

• 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.

• 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

• 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

• 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

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

• 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.)

• 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

• 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

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

• 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

• 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

• 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

• 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 (?)

• 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

• 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

• 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

• 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

• 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.

• 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.

• 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)

• 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.