AP Psychology Outline
Chapter 2: The Research in Psychology
Red – Definition
Blue - Important Points
Green - Important People & Contributions
Scientific Approach to Behavior
- The Scientific Approach assumes that events are governed by laws.
- Psychologists assume Behavior is governed by laws. (Like the Earth is governed by the law of Gravity.)
- 3 Goals of Scientific Enterprise
i. Measurement & Description – Develop Measurement techniques that describe behavior clearly and precisely.
ii. Understanding & Prediction – Make and Test predictions called Hypothesis.
1. Hypothesis – Statements about the relationship between two or more variables.
2. Variables – Any measurable characteristics or behaviors that are controlled or observed in a study.
iii. Application & Control – Apply research findings to help practical problems.
1. Theory – The system of related ideas used to explain a set of observations. Must be testable. Based upon experiments and evidence. Is always subject to revision.
Steps in a Scientific Investigation
- Step 1: Formulate a Testable Hypothesis
- Scientific Hypothesis must be formulated precisely, and variables under study must be clearly defined.
- Operational Definition – Describes the action or operation used to measure or control a variable.
- Step 2: Select Research Method & Define Study
- Put Hypothesis in an Empirical Test
- Empirical – Knowledge should be acquired through Observation.
- Research Method.
- Define the Study by collecting Participants/Subjects.
- Participants/Subjects – Persons or Animals whose behavior is observed in a study.
- Step 3: Collect the Data
- Data Collection Techniques – Procedures for Making Empirical Observation and Measurements.
- Examples include (Direct Observation, Questionnaire, Interview, Psychological Test, Physiological Recording, or Examination of Archival Records.)
- Step 4: Analyze the Data & Conclusion
- Use Statistics to analyze data and find if Hypothesis is supported.
- Conclude upon the Findings.
- Step 5: Report the Findings
- Give the findings to the public so it can be tested. Such as a journal.
- Journal – Periodical that publishes scholarly material, in a narrow field.
Advantages of Scientific Approach
- Clarity and Precision
- Small amount of Error
- Experiment – Research Method where a variable is manipulated and changes to the second variable is observed.
i. Independent & Dependent Variables
1. Independent Variable – Variable that is controlled by the Experimenter to see its impact on the other Variable.
2. Dependent Variable – Variable that is affected by the Independent (Controlled) Variable.
Experimental & Control Groups
- Experimental Group – Subjects who receive special treatment in regard to the Independent Variable.
- Control Group – Similar Subjects who do not receive special treatment given to experimental group.
- The Differences between the two Groups are the findings.
- Extraneous Variables – Any variables other than the Independent variable that seems likely to influence the Dependent variable in a study.
- Confounding of Variables – When two Variables are linked together in a way that makes it harder to sort their specific effects. Causes great harm to Experiments.
- Random Assignment – Occurs when all subjects have an equal chance of being assigned to any group in the study.
Variations in Designing Experiments
- There can be numerous Independent or Dependent Variables.
- It is sometimes smarter to use only 1 group of students, who serve as their own Control Group.
- Interaction – Effect of one variable depends on the Effect of another.
Advantages & Disadvantages of Experimental Research
- Experiments are often artificial, and the decisions based practically might be different of the subjects.
- Ethical concerns prohibit some experiments.
- Some manipulations of variables are nearly impossible.
- Used when Psychologists cannot control the variables they want to study.
- Includes Naturalistic Observation, Case Studies, and Surveys.
- Method permits investigators to only describe patterns of behavior and discover links or associations between variables.
- Naturalistic Observation – A researcher engages in careful Observation of behavior without directly intervening with the subjects.
- Case Study – In-Depth investigation of an individual Subject.
- Generally do not conduct Empirical Data.
- Is Highly Subjective to debate.
- Survey – Researchers use Questionnaires or Interviews to gather information about specific aspects of participant’s background and behavior.
- They depend on Self-Report data, which a variety of factors can distort the true data.
Disadvantages of Descriptive/Correlational Research
- Investigators cannot control events to isolate cause and effect.
- Cannot factually demonstrate the link between 2 Variables.
Statistics and Research
- Statistics – Use of Math to interpret, organizes, and summarizes numerical data.
- 2 types: Descriptive Statistics, and Inferential Statistics.
- Descriptive Statistics – Used to Organize and Summarize Data.
- Central Tendency (Typical Score)
i. Median –The score that falls exactly in center of distribution of scores.
ii. Mean – Arithmetic average of scores.
iii. Mode – Most frequent score.
i. Variability – How much the scores in a data set vary from each other and from the mean.
ii. Standard Deviation – index of amount of Variability in a set of data.
i. Correlation – When two variables are related to each other.
ii. Correlation Coefficient – Numerical index of the degree of relationship between two variables.
1. Indicates Direction (positive or negative) of relationship
2. Indicates how strongly the two Variables are related.
iii. Positive vs. Negative Correlation
1. Positive Correlation – the two variables co-vary in the same direction.
2. Negative Correlation – The two variables co-vary in the opposite direction.
iv. Strength of Correlation
1. Strength related between 1.00 and -1.00.
2. Closer to 1.00 or -1.00, the stronger the Correlation.
v. Correlation & Prediction
1. As the Corollary increases in strength, the ability to predict one variable based on the other increases.
vi. Correlation and Causation
1. Corollary is not equivalent to Causation
2. The Corollary could be affected by a third unknown variable that really is the reason for the interaction.
- Inferential Statistics
i. Inferential Statistics – Used to interpret data and draw conclusions.
ii. Statistical Significance – Exists when the probability that the observed findings are due to chance is very low. (Less than 5%)
- Replication – Repetition of the study to see whether the earlier results happen again.
- Sampling Bias
i. Sample – Collection of subjects selected for observation.
ii. Population – Much larger collection of Animals or People from where Sample is drawn.
iii. Sampling Bias exists when a sample is not representative of the population from which it was drawn.
- Placebo Effect
i. Placebo Effect – When participant’s expectations lead them to experience some changes even though they receive not actual treatment.
ii. Is assessed by the inclusion of a fake version of experimental treatment in a study without telling the subject.
- Distortions in Self-Report Data
i. Social Desirability Bias – The tendency to give socially approved answers to questions about oneself.
ii. Response Set – Tendency to respond to questions in a particular way that is unrelated to the content of the questions.
1. Some people tend to agree with everything on a questionnaire.
- Experimenter Bias
i. Experimenter Bias – When a Researcher’s expectations or preferences about the outcome of a study influence the results obtained.
ii. Double-Blind procedure – Research strategy in which neither subjects nor experimenters know which subjects are in the experimental or control group. To combat Experimenter Bias.
- The major Ethical dilemmas reflect upon use of deception, and the use of animals.
i. Lying is immoral, so shouldn’t be used in experiments.
ii. Honesty vs. Knowledge
- Animal Research
i. Most research upon animals done because not allowable with Humans.
ii. Most controversy around using animals as subjects in pregnancy and birth defects.
iii. PETA is leading group against Animal Research.
- Ethical Principles in Research
i. People’s participation in research should be voluntary, and they can withdraw at any time.
ii. Participants should not be subjected to harmful or dangerous treatments.
iii. If deception is used in a study, participants need to be debriefed as soon as possible.
iv. Subject’s right to privacy should never be violated.
v. Harmful or painful procedures on animals must be thoroughly justified by potential benefits of research.
vi. Research animals are entitled to decent living conditions.