Wildemuth chapter 11
definition used for accessing causal relationships by determining the impact of an intervention – teaching technique, electronic database or collection development Powell's policy or an outcome or effect of interest
Preexperimental designs
true experimental designs
quasiexperimental designs – used in natural setting/some control over the experimental conditions can be exerted you full control is either not possible or not desirable
distinguish first how these differ from those other types of designs – the pre-experiment and the true experiment
Amount of control exerted on next rainiest variables is the primary distinction between cause site experimental studies and true experimental studies
lack of control associated with the absence a random assignment
involve naturally occurring groups
only in true experiments are individual subjects randomly assigned to particular experimental conditions
quasiexperimental methods are designed for settings where utter designs are not feasible
when it's not possible to exert such control – random assignment or some other way/quasiexperimental designs offer an alternative for the researcher
Design lacks complete experimental control/weaker than true experiments
most appropriate approach for many types of studies of interest in information and library science
implemented in a more naturalistic setting – rather more control controlled laboratory setting
increasing ecological validity of the study
attainable in real-world settings
controlled experimentation in a laboratory setting may not translate to success and less controlled natural context
Use of quasiexperimental designs in information library science
Apply to 8 to 10% of research studies in the field of ILS
evidence suggests that two experiments designs are used considerably less frequently than quasiexperimental designs
Typically pragmatic rather than theoretical in nature take the form of applied research
within the framework of action research designs
to actively and directly impact procedures and services with the in a practice setting
research areas include instruction, evaluation, information seeking and professional development
Specific single and multi group designs demonstrate useful designs particularly appropriate for application ILS
Timeseries designs – based on intermittent measurements taken before an exposure to the treatment
within subjects designs
minimum of two data collections points in total encourages use of more than minimum for sufficient opportunities to assess effects of the treatment new paragraph non-equivalent control group design – most likely most frequently apply type also referred to his non-equivalent groups design/pretest posttest not equivalent couple control group design
control comparison study
counterbalance design – multiple treatments are interventions applied to each of the subjects
wrist is design and in interpretation any difference in results can be attributed to the treatment or intervention imposed by the researcher
such as bias and mortality affects – selection bias occurs when the groups being compared are different from each other in some systematic way
history affects – unrelated events associated with the study participants/that is their history during the course of the study
testing affects – pretest of some kind may influence ability ability of your study in two ways first administer close together in time/subject may recall the responses on the pretest to match those or change them for the posttest
second pretest questions may actually condition subjects responses to the intervention causing them to enact interact with it differently than if they had not completed the pretest paren reactive effective testing)
additional threats to be dealt validity
Very useful in situations which make it possible to implement a true experiment/cannot make comparisons/cannot randomly assign research subject to the two groups, plus I experimental design may allow you to address research questions with a balanced combination of rigor and naturalism
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