Study Unit 5: Research design Flashcards
what is internal validity:
extent to which the study confirms the existence of a cause-effect relationship
what are confounding variables
Confounding variables (variables that confound or confuse the interpretations) are also called nuisance variables or extraneous variables.
name some threats to internal validity
History refers to uncontrolled events that influence the outcome of the research. If an event that is not related to the study occurs during the study and influences the dependent variable, this event will confuse the causal relationship that the researcher assumes exists
There may be changes within the subjects themselves over time. The subjects being studied may undergo physical or psychological changes (this is known as maturation)
Instrumentation is a threat to the validity of the study if the measuring instrument deteriorates or improves over time.
Selection of subjects to be assigned to a specific group could bias the study if there are important, unsuspected differences between the subjects in each group.
Mortality refers to the fact that some subjects do not continue throughout the study, but drop out (not necessarily die!) before it is completed. The subjects who drop out may be different from those who complete the study and this could well influence the results.
Regression effect refers to a tendency of extreme scores to move towards the average upon retesting
testing effect implies that subjects may become familiar with the testing procedure or be more aware of certain issues after the pretest.
what is external validity:
extent to which results can be generalised to other populations or circumstances
what is Researcher expectancy
refers to the situation where expectations cause a researcher to behave in a manner that makes the expected event more likely to occur.
what are treatments
This deliberate action on the part of the researcher is called a treatment. Treatments are any intervention that modifies or changes the situation. Treatments could include counselling, showing a video, using specific teaching strategies,
what is a treatment condition
Treatment condition refers to whether a particular group receives the treatment or not, and what kind of treatment it receives.
what is the experimental group:
group that receives the treatment
what is the
what is the control group:
group that does not receive the treatment
what is a pretest
If the dependent variable is measured before the introduction of the treatment, this is called a pretest
what is a posttest
posttest is the measurement of the dependent variable after the treatment has been introduced
what is random assignment
: every subject has an equal chance of being assigned to any treatment condition or group
why should pre experimental designs be avoided
Pre-experimental designs may or may not involve manipulation of treatment conditions, but they do not include randomisation.
what are quasi experimental designs
Quasi-experimental designs resemble true experimental designs in that the researcher aims to establish cause-effect relationships
These designs are better than pre-experimental designs for identifying causal relationships;
quasi-experimental designs do not involve randomisation
what is a time series design
time-
series design: comparing a number of observations of the same group over a period of time
what is single case experimental design
single-case experimental design: to assess interventions in educational, clinical and counselling settings
what is a classification factor
study the difference between existing groups that have been classified according to fixed levels of an independent variable. This type of variable is referred to as a classification factor;
what is meant by ex post facto
Ex post facto research deals with relationships between two or more variables without any planned intervention.
comment on survey research
survey research: the purpose of a survey research is to describe the population’s attitudes, opinions, etcetera based on sample research
discuss five strategies identified by Creswell as representative of common practice in qualitative research
Biography
is used to document an individual’s life and experiences, as told to a researcher or found in documents and archival material.
Phenomenology aims at understanding and interpreting the essence of the meaning that subjects give to their daily lives.
Grounded theory refers to the creation of a theory based more (but not exclusively) on observation than on deduction. …
Ethnography is the study of an intact cultural or social group, characterised by (participant) observation, description and interpretive data analysis.
Case study is the observation of a process, activity, event, programme or individual bound within a specific time and setting
what are basic principles of qualitative research
- boundaries (i.e. the scope of the research)
- design flexibility
- the research relationship
- intended outcome
what is meant by scope
scope: range of situations, techniques, and observations included in the research
