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EVAL 6000: Foundations of Evaluation. Dr. Chris L. S. Coryn Kristin A. Hobson Fall 2012. Agenda. Stage One theories Donald T. Campbell Questions and discussion Encyclopedia of Evaluation entries.
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EVAL 6000: Foundations of Evaluation Dr. Chris L. S. Coryn Kristin A. Hobson Fall 2012
Agenda • Stage One theories • Donald T. Campbell • Questions and discussion • Encyclopedia of Evaluation entries
“We would improve program evaluation if we were alert to opportunities to move closer to the experimental model” — Donald T. Campbell
Biographical Sketch • Born in 1917, died in 1996 • Ph.D. in Psychology, University of California, Berkeley • Author or more than 235 publications • Recipient of numerous honorary degrees, awards, and prizes • Intellectual work included psychological theory, methods, sociology of science, and epistemology
Campbell’s View of Evaluation • Evaluation should be a part of a rational society in which decisions depend on the results of rigorous tests of bold attempts to improve social problems • Evaluators should play a servant-methodologist role rather than an advisory role commensurate with democratic values
Campbell’s Influence • Lionized as the father of scientific evaluation • Developed and legitimated scientific methods of evaluation • The utopian view of an ‘experimenting society’
Campbell’s Major Contributions • Evolutionary epistemology • Validity theory and threats to validity • Experimental and quasi-experimental methods • Open, mutually reinforcing but critical commentary on knowledge claims (a disputatious community of truth seekers)
Randomized Experiments • Provide ‘best’ scientific evidence of cause-and-effect relationships • Premised on expectancy of equivalence of units through randomly assigning units to two or more conditions • Priority is to reduce internal validity threats
Validity • The approximate truthfulness or correctness of an inference or conclusion • Supported by relevant evidence as being true or correct • Such evidence comes from both empirical findings and the consistency of those findings coupled with other sources of knowledge • Is a human judgment and fallible • Not an either or claim, it is one of degree
Major Types of Validity • Internal validity: The validity of inferences about whether the relationship between two variables is causal. • Construct validity: The degree to which inferences are warranted from the observed persons, settings, treatments, and cause-effect operations sampled within a study to the constructs that these samples represent. • External validity: The validity of inferences about whether a causal relationship holds over variations in persons, settings, treatment variables, and measurement variables. • Statistical conclusion validity: The validity of inferences about the covariation between two variables.
Threats to Internal Validity • Ambiguous temporal precedence: Lack of clarity about which variable occurred first may yield confusion about which variable is the cause and which is the effect • Selection: Systematic differences over conditions in respondent characteristics that could also cause the observed effect • History: Events occurring concurrently with treatment that could cause the observed effect • Maturation: Naturally occurring changes over time could be confused with a treatment effect
Threats to Internal Validity • Regression: When units are selected for their extreme scores, they will often have less extreme scores on other variables, an occurrence that can be confused with a treatment effect • Attrition: Loss of respondents to treatment of to measurement can produce artifactual effects if that loss is systematically correlated with conditions • Testing: Exposure to a test can affect scores on subsequent exposures to that test, an occurrence that can be confused with a treatment effect • Instrumentation: The nature of a measure may change over time or conditions in a way that could be confused with a treatment effect • Additive and interactive threats: The impact of a threat can be additive to that of another threat or may depend on the level of another threat
Campbell’s Theory of Social Programming • Three worlds • The current world: Client needs are not the driving force behind political and administrative behavior • The current world as it can be marginally modified: Improvement through demonstrations • The utopian world: Critical reality checks and the experimenting society
Campbell’s Theory of Knowledge Construction • Grounded in epistemological relativism (knowledge is impossible without active knowers) • Never knowing what is true and imperfectly knowing what is false • Evolutionary theory of knowledge growth • Not all methods yield equally strong inferences
Campbell’s Theory of Valuing • Valuing should be left to the political process, not researchers (descriptive valuing) • Evaluators are not the arrogant guardians of truth • Multidimensional measurement that is inclusive of democratic values
Campbell’s Theory of Knowledge Use • Use is the concern of the political process, not evaluators • Evaluations are only worth using if they have withstood the most rigorous tests • Most concerned with misuse • Methodological biases • Control of content or dissemination
Campbell’s Theory of Evaluation Practice • Application of experimental design to answer summative questions • Priority given to internal validity • Theoretical explanation is best left to basic researchers • Evaluation resources should be focused on pilot and demonstration projects
Encyclopedia Entries • Bias • Causation • Checklists • Chelimsky, Eleanor • Conflict of Interest • Countenance Model of Evaluation • Critical Theory Evaluation • Effectiveness • Efficiency • Empiricism • Independence • Evaluability Assessment • Evaluation Use • Fournier, Deborah • Positivism • Relativism • Responsive evaluation • Stake, Robert • Thick Description • Utilization of Evaluation • Weiss, Carol • Wholey, Joseph