Psychological Methods

Questions to Answer How do psychologists use the scientific method to study behavior and mental processes? What methods of research are appropriate for the study of different behaviors? How do psychologists draw appropriate conclusions about behavior from research? How do psychologists make ethical decisions in research? Psychological Methods 2011

Topics Scientific method Basic techniques Issues and ethics Observation Testing Naturalistic Participant Laboratory Longitudinal Cross-Sectional Case Study Survey Experimental Issues and ethics Psychological Methods 2011

Terms THEORY A general statement about the relationship between variables HYPOTHESIS A specific statement about the relationship between two or more variables OBSERVATION The formal collection of data to prove or disprove a specific hypothesis Psychological Methods 2011

Where Research is done Laboratory Field Benefits Control Clear measurement No extraneous variables Problems Generalizability Realism Field Benefits Realism Generalizability Problems Control Psychological Methods 2011

Psychological Methods 2011

1. Form research question Scientific Method 1. Form research question Daily experience Folklore or common knowledge Psychological theory Psychological Methods 2011 Psychological Methods 2011

Educated guess If…Then Scientific Method 2. Form a hypothesis Psychological Methods 2011

Scientific Method 3. Test the hypothesis Observation Case Study Survey Experiment Psychological Methods 2011

Scientific Method 4. Analyze the results Collect and analyze data Patterns and relationships Correlations Measures of central tendency Mean, Median, Mode Psychological Methods 2011

Scientific Method 5. Draw a conclusion 6.Replicate Do results support the hypothesis? Does hypothesis require modification? 6.Replicate Psychological Methods 2011

The Scientific Method 1. Research question 2. Form a hypothesis 3. Test the hypothesis 4. Collect and analyze data 5. Form a Conclusion 6. REPLICATE! Psychological Methods 2011

Methods of Observation 1. Testing method Tests measure elements of behavior: abilities, interests, personality Insight on certain aspects of abilities or behavior May be incomplete or inaccurate Psychological Methods 2011

Methods of Observation 2. Natural observation Observe behavior in natural habitats No control over setting or events Answers what? but not why? Psychological Methods 2011

Advantages Identify relevant variables and possible environmental influences on behavior Record behavior in risky or dangerous situations Explore the generalizability of laboratory finding Psychological Methods 2011

3. Participant Observation Methods of Observation 3. Participant Observation Researcher participates in the group while recording its behavior ACTIVE PARTICIPATION: Researcher is actively engaged in the group’s activities PASSIVE PARTICIPATION: Researcher is known to participants but doesn’t become engaged in their activities Psychological Methods 2011

3. Participant Observation ADVANTAGES PROBLEMS Best used with an isolated group Direct understanding of group dynamics Record rare and fleeting events Understanding of risky or dangerous events Bias Selective attention Record keeping Access Ethics Privacy Confidentiality Typicality of the group Psychological Methods 2011

Methods of Observation 4. Laboratory Observation Control Can’t duplicate real life environment Psychological Methods 2011

Methods of Observation 5. Longitudinal Method Participants observed over long period of time Observe change over time Time consuming, expensive Psychological Methods 2011

Methods of Observation 6. Cross-sectional Method Takes less time Differences may not be due to age or development Compare people in different age groups at different times Psychological Methods 2011

Case Study Method In-depth investigation of individuals or small groups Insight to specific cases Generalizable? May focus on isolated incidents Questioning technique may bias answers Psychological Methods 2011

Survey Method Series of questions about a particular subject Sample is part of a target population Random sample Stratified sample Random sample is selected by chance; each member has equal chance of being chosen Stratified sample represents all groups proportionally Random chosen by chance, equal chance of being chosen. Stratified represents all groups proportionately Psychological Methods 2011 Psychological Methods 2011

Problems of the Survey Method Imprecise questions Volunteer bias People who volunteer to participate are usually more willing to disclose personal information and are more interested in the research Psychological Methods 2011 Psychological Methods 2011

Analyzing Observations CORRELATION How closely is one thing related to another? Psychological Methods 2011

Cannot determine cause and effect Limits of Correlation Cannot determine cause and effect Insufficient basis to conclude that one thing causes another Psychological Methods 2011

CORRELATION CAUSATION WARNING! CORRELATION CAUSATION Psychological Methods 2011

Example While conducting research in Helsinki, Finland a demographer found that the correlation between the number of stork nests on chimneys was positively correlated (r=.38) with birth rate. Psychological Methods 2011

Male storks make babies in unfaithful human females. Conclusion Storks bring babies Male storks make babies in unfaithful human females. Babies make storks. I haven’t the slightest idea. Psychological Methods 2011

Experimental Research EXPERIMENTAL GROUP: The group that gets the treatment you are interested in CONTROL GROUP: A group included in the experiment that does NOT get the experimental treatment. Psychological Methods 2011

Experimental Research Independent variable: controlled by experimenter Dependent variable: depends on change in independent variable Psychological Methods 2011

Experimental Research Confounding variables: variables that the researcher fails to control or eliminate, damaging the validity of an experiment. Psychological Methods 2011

Issues in Experimental Research Confounding Variables Placebo effect Blind studies Ethics Psychological Methods 2011

Example HYPOTHESIS: People listening to aggressive classical music will feel more aggressive than people who listen to calming music EXPERIMENTAL GROUP Group that gets the treatment (music) CONTROL GROUP Group that does not get the experimental treatment (silence) DEPENDENT VARIABLE The variable that is measured in an experiment (mood) INDEPENDENT VARIABLE The treatment the experimenter controls (type of music) Psychological Methods 2011

EXAMPLE You have been asked to design an experiment that demonstrates that women who have tattoos are seen as being more attractive than women without tattoos. EXPERIMENTAL GROUP? CONTROL GROUP? INDEPENDENT VARIABLE? DEPENDENT VARIABLE? Psychological Methods 2011

RESEARCH ISSUES People’s behavior changes when they know they are being watched Knowledge of the research hypothesis may influence a person’s behavior Deception: research design requires the researcher to give misleading information to participants (Is it ethical?) Protection from harm Informed consent Debriefing Psychological Methods 2011

- Can be used to determine cause and effect relationships   Pros Cons Descriptive Methods: 1. Case Study - Allows for in-depth study - can study things otherwise impossible to study (brain damage, for example) - single subject may not be representative; could be a fluke - only describe behavior; do not tell us cause and effect (or “why?”) 2. Survey - can measure attitudes, motives, and opinions - can get a lot of data easily - wording of the questions can drastically affect results - relies on honesty and reflection of participants small rate of return is not likely to be representative (volunteer bias) 3. Naturalistic Observation - results have ecological (real world) significance 4. Laboratory Observation - useful for predicting behavior - provides quantitative data about the strength of the relationship Experimentation: 1. Experiment - Can be used to determine cause and effect relationships - may lack real-world significance - ethical issues may limit possibilities. Psychological Methods 2011