Chapter 9- Quantitative Research Designs Flashcards
Def descriptive studies
Phenomena are described or the rship bx 2 variables is examined
Def exploratory studies
Conducted when little is known abt the phenomenon of interest
Def explanatory studies
Search for causal explanations and are much more rigorous than explanatory or descriptive
Experimental res is concerned with what type of rships?
Cause and effect
Def Extraneous variables
Variables that the researcher is not able to control or does not choose to control
What are extraneous variables aka?
Confounding
Intervening
Study limitations
Def internal validity
Degree to which changes in the dependant variable (effect) can be attributed to the independant variable (cause)
What are threats to internal validity?
Factors other than the independent variable that influence the dependant variable
Def external validity
The degree to which study results can be generalized to other ppl and other settings
As the researcher attempts to control for internal validity, external validity is usually _______
Decreased
Name the threats to internal validity (6)
Selection bias History Maturation Testing Instrument change Mortality
Def selection bias
When study results are attributed to the experimental tx or the researchers manipulation of the independant variable, when in fact the results are related to subject differences before the independant variable was manipulated.
When shouldn selection threat be considered?
In experimental studies when subjects are randomly assigned to experimental and comparison groups
Def history threat
When some event besides the experimental tx occurs during the course of the study, and this event influences the dependent variable
How is history threat controlled
By the inclusion of at least one simultaneous control or comparison group in a study
Def maturation threat
When changes that occur within the subjects during the experimental study influence the study results
When does a testing threat occur
In studies where a pretest is given or where sects have knowledge of baseline data
Def testing threat
The influence of the pretest or knowledge of baseline data on the post test scores
Def Instrumentation change threat
The difference bx the pretest and post test measurements caused by a change in the accuracy of the instrument or the judges rating, rather than as a result of the experimental tx
How do judges factor into instrumentation changes?
Judges may become more adept at the ratings, or become tired and make less exact observations
Def mortality threat
When the subjects do not complete the study
3 threats to external validity
Hawthorne effect
Experimenter effect
Reactive effects of the pretest
Def Hawthorne effect
When study participants respond in a certain manner bc they a aware that they are being observed
How can researchers control the Hawthorne effect?
By using a double blind experiment
Def double blind experiment
Neither the researcher nor the participants are aware of which participants are in the experimental group and which are in the control group
Def experimenter effect
When researcher characteristics or behaviors influence subjects behaviors
Def rosenthal effect
Used to indicate the influence of the interviewer on respondents answers
Def reactive effects if the pretest
Occurs when subjects have been sensitized to the tx bc took the pretest
Symbolic representations of research designs
R, X, O
R= random assignment of subjects to groups X= experimental tx or intervention O= observation or measurement of dependant variable
Def random assignment
A procedure that ensures that each subject has an equal chance of being assigned or placed in any of the groups in an experimental study
Name the 3 types of experimental designs
True experimental
Quasi experimental
Pre experimental
Def true experimental designs
When the researcher has a great deal of control over the research situation
3 criteria for experimental design
Researcher manipulates experimental variables
One experimental group and one control group
Subjects are randomly assigned
Def manipulation
The independant or experimental variable is controlled by the researcher
Def control group
Group in an experimental study that does not receive the experimental tx
Comparison group
Any group in an experimental study that either receives no treatment or a treatment that is not thought to be as effective as the experimental treatment
Def pretest- post test control group design
Subjects are randomly assigned to groups
Pretest given to both groups
Experimental group receives the tx and the comparison group receives the routine tx/no tx
Post test given to both groups
Def post-test only control group design
Subjects are randomly assigned
Experimental group receives tx and the comparison group receives no/routine tx
Post-test given to both groups
Def Solomon 4 group design
Subjects are randomly assigned to one of four groups
2 groups experimental and 2 comparison
Post test given to all 4 groups
Advantages of the Solomon 4 - group design ( 2)
Most prestigious experimental design
Minimizes threats to internal and external validity
Disadvantages of Solomon 4 group design
Design requires a large sample size
Statistical analysis of data is complicated
Name the 3 true experiment designs
Pretest- post test control group design
Post test only control group design
Solomon 4 group design
Def quasi experimental designs
Designs in which there is no comparison group or subjects are not randomly assigned to groups
Name the two quasi experimental designs
Non-equivalent control group design
Time-series design
Def non equivalent control group design
Similar to pre test post test design except for no random assignment of participants to the experimental and comparison groups
Def time-series design
A researcher periodically observes or measures the subjects
Def pre experimental designs
Experimental designs that are very weak and in which the researcher has little control over the research
Name the 2 pre-experimental designs
One shot case study
One group pretest- post test design
Def one shot case study
a single group is exposed to an experimental tx and observed after tx
Def one group pretest - post test design
Provides a comparison bx a group of subjects before and after the experimental tx
What is non experimental research
Descriptive research bc there is no manipulation or control over the variables
Are there cause and effect rships in nonexperimental research?
No
Name the types of non experimental designs (5)
Survey studies Correlational studies Comparative studies Methodological studies Secondary analysis studies
Def survey studies
Self report eat are collected from samples with the purpose of describing populations on some variables of interest
What ways can survey studies be conducted
Phone
Mail
Internet
Interview
What are the 2 most common data collection techniques in survey studies
Questionnaires
Interviews
2 advantages of survey studies
Ability to provide accurate information on pops using relatively small samples
Large amt of data can be obtained rather quickly and with minimal cost
Def correlational studies
Researchers examines strength of relationships bx variables by determining how changes in one variable x is related to another variable y
Def correlation
The extent to which one variable x is related to another variable y
Def Correlation coefficient
The magnitude and direction of the rship bx 2 variables
May be positive 1 or negative 1
Def positive relationship
As the value of 1 variable increases. The other variable increases
Aka direct rship
Def negative relationship
As the value of one variable increases, the value of the other variable decreases
Aka inverse relationship
Def comparative studies
Examine the differences bx intact groups on some dependant variable of interest
What is the difference bx comparative studies and experimental studies
Researchers ability to manipulate the independant variable. On comparative studies, there is no manipulation of the independant variable
How are comparitive studies classified? (2)
Retrospective or prospective
Def retrospective studies
Defendant variable (effect) is identified in the present and an attempt is made to determine the independent variable that occurred in the past
Def prospective studies
The independent variable or presumed cause is identified and then subjects are then followed in the future to observe the dependent variable
Def ex post facto studies
Data are collected after the fact
Variations in the independant variable studied after the variations have occurred, rather than at the time of the occurrence
Def methodological studies
Concerned with the development, testing, and evaluation of research instruments and methods
Def secondary analysis studies
Data are analyzed that were gathered in the previous study
Researchers may test new hypoth or ask new res questions
Advantages of secondary analysis studies (2)
Efficient
Economical
List the settings for research (3)
Laboratory
Field
Simulation
Def laboratory studies
Subjects are studied Ina special env created by the researcher
Def field studies
Studies conducted in the field or real life situations
1 disadvantage of field studies
Not much control can be maintained
Def simulation studies
Considered lab studies
Researcher measures responses to descriptions of case studies that are intended to rep real life situations
