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


    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.

    Can isolate cause and effect
    Can control experimental factors
    Results may not generalize to other contexts
    Some experiments may not be ethical


    A technique for ascertaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group.
    Looks at many cases at once
    Fairly inexpensive
    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.
    Only requires one participant
    Suggests further study
    Good for investigating a certain phenomenon
    Creates a detailed profile
    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.
    Allows researchers to study behavior under natural conditions
    Does not explain behavior
    Observations may be biased
    Researchers often have trouble making their observations without affecting their subject's behavior


Research Essential Vocabulary


   An explanation using an integrated set of principles that organizes and predicts behaviors and events.
   A testable prediction about the possible relationship between two or more variables.
   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.
   The extent to which a study's findings can be reasonably assumed to apply back onto the study’s population.”
   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.



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.