LESSON 9 Flashcards
the degree to which changes in the dependent variable can be attributed to the independent variable
internal validity
this exists when study results are attributed to the experimental treatment
selection bias
this ‘‘occurs when some events besides the experimental treatment takes place’’ during the course of the study affects or influences the dependent
history
takes place when ‘‘changes within the subjects occur’’ during the experimental study
maturation
this refers to the influence of the pre-test which already projects the result of the post test scores
testing
the ‘‘existence of a difference between pre-test and post test’’ results caused by change in the accuracy
instrumentation change
this happens when a ‘‘difference exists between the subject dropout rates’’ of either the experimental group and the control group
mortality
this degree to which study results can be ‘‘influenced or affected by external factors or population and settings’’
external validity
occurs when study participants ‘‘respond in a particular manner or there is obvious change of behavior’’
hawthorne effect
a ‘‘threat to the study’’ which results when the researcher’s behavior influences the behavior of the subjects
experimental effect
the ‘‘subjects have been sensitized to the treatment’’ by taking the pre-test and thereafter influence the post test results
reactive effect of the pre test
the tendency of the researcher to ‘‘rate the subject high or low’’ because of the impression
halo effect
the study when the subject does not know whether he or she is receiving the treatment or a placebo
blind experiment
it is used to removed the observer’s bias. this means neither the subject nor the observer knows the specific research objective or the specific subjects
double blind method
may be used to ‘determine the extent of bias the two observers as they both observe and record the subjects performance’
double observer method
