Experimental And Quasi-Experimental Design Flashcards
Experimental design
Objective, systematic, controlled investigation to examine the probability and causality among selected independent and dependent variables to predict and control phenomena
Randomization
Each subject has an equal chance of being assigned to either experimental or control group, eliminates systematic bias
Control
Manipulating independent variable, randomly assigning groups, careful preparation of experimental protocols, strict adherence to protocols, comparison group
Manipulation
Design identifies the independent variable and how it will be changed within the experiment, focuses on difference between control and experimental groups
Antecedent variables
Variables that occur before the study but may impact the dependent variable and confound results
Intervening variables
Condition that occurs during the course of the study and is not part of the study, may affect dependent variable
True experimental method
Examines degree of differences between group scores in post-test, attrition can impact results, uses pretest-post-test measurement tool
Solomon four group design
Having 4 groups to reduce threats to internal validity, attrition is a threat.
After-only design
Post-test only control group, useful when exploring major problems or when the number of participants is limited
Quasiexperimental design
Intended to test cause and effect relationships, however full experimental control is not possible, lacks randomization
Nonequivalent control group design
Looks exactly like experimental design but participants are not randomized
Priori
An understanding of content that comes from theoretical deduction or learning rather than from observation or experience
Non-experimental designs
Used to construct a picture of a phenomenon, explore events as they naturally occur, and test relationships and differences among variables. Independent variable is not manipulated
Survey
Design style used when very little is known about variables, descriptions of variables are collected and analyzed to assess current practice conditions
Superficial, time consuming, requires experience
Disadvantages to survey designs
Correlational studies
Investigation between two or more variables to examine type and strength of the relationship, not cause and effect
Developmental studies
Examine the relationship, differences, and status of variables or phenomena at a point in time, how the phenomena will change over time
Cross-sectional design
Examine groups of subjects in various stages of development simultaneously with the intent of inferring trends over time, data collection occurs once
Longitudinal study
Examines same subjects over an extended period of time, multiple data collections
Retrospective or ex post facto
Used to determine meaningful relationships between events that have occurred in the past
Methodical research
Focused on developing the validity and reliability of instruments to measure research concepts
Psychometric research
Focused on the theories and techniques involved in measuring psychological constructs
Systematic review
Structured, comprehensive synthesis of quantitative studies on a specific topic
Meta analysis
Statistical pooling of results from several studies into one single quantitative analysis
