
Learning Objectives
The Students Will:
Explain how psychology uses the experimental method to understand behavior.Describe the scientific method and its strengths.
Understand the importance of the scientific method to psychology.
Elaborate on the role of control and bias in psychological research.
Explain the concept of correlation, it's use in psychology, and why it does not imply causation.
Understand the importance of reliability and validity.
Explain the strengths and weaknesses of the experimental method.
Types of Research
Experiment
A research method in which an investigator manipulates one or more factors (independent variables) to observe the effect on some behavior or mental process (the dependent variable). By random assignment of participants, the experimenter aims to control other relevant factors.
Pros
Can isolate cause and effect
Can control experimental factors
Cons
Expensive
Results may not generalize to other contexts
Some experiments may not be ethical
Survey
A technique for ascertaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group.
Pros
Looks at many cases at once
Fairly inexpensive
Cons
Wording effects results
participants can lie
Only gives correlational data
Survey return rates are low when participants are asked to respond
Case Study
An observation technique in which one person is studied in depth in the hope of revealing universal principles.
Pros
Only requires one participant
Suggests further study
Good for investigating a certain phenomenon
Creates a detailed profile
Cons
May not discern general truths
can't be generalized to larger population
Naturalistic Observation
Observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation.
Pros
Allows researchers to study behavior under natural conditions
Cons
Does not explain behavior
Observations may be biased
Researchers often have trouble making their observations without affecting their subject's behavior
Research Essential Vocabulary
Theory
An explanation using an integrated set of principles that organizes and predicts behaviors and events.
Hypothesis
A testable prediction about the possible relationship between two or more variables.
Population
All the cases in a group, from which samples may be drawn for a study.
Random Sample
A sample that represents a population because each member has an equal chance of inclusion.
Random Assignment
Assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups.
Experimental Group
The group that is exposed to the Independent Variable.
Control Group
The group that is not exposed to the Independent Variable and acts as a baseline for results.
Independent Variable
The experimental factor that is manipulated; the variable whose effect is being studied.
Dependent Variable
The factor that is being measured that may have been changed due to exposure to the independent variable.
Generalizability
The extent to which a study's findings can be reasonably assumed to apply back onto the study’s population.”
Replication
Repeating the essence of a research study to see whether the basic finding extends to other participants and circumstances.
Operational Definition
A statement of procedures used to define research variables. Aids in replication.
Double-Blind Procedure
Both the research staff and subjects do not know who has received the treatment or placebo.
Placebo Effect
Experimental results, particularly in the Control Group,caused by expectations alone, not by the Independent Variable.
Confounding Variable
An extraneous variable that varies systematically with the IV so we cannot be sure of the true source of the change to the DV.
Hindsight Bias
The tendency to believe, after learning an outcome, that one had seen it all along.
Illusory Correlation
The perception of a relationship where none exists; correlation is not causation.
Confirmation Bias
A tendency to search for information that supports our preconceptions and to ignore or distort contradictory evidence.
False Consensus Effect
The tendency to overestimate the extent to which others share our beliefs and behaviors.
Statistical Significance
A statement of how likely it is that findings occurred by chance or by result of the experiment.
Sampling Bias
When a sample is collected where some members of the intended population are less likely to be included than others.
Worksheets
The Research Process: Create your own psychology research project by filling out the worksheet and applying what you know. Ethics or cost should be addressed. Find another student and compare notes with their research proposal to complete the worksheet.
Videos