7-13 (Final) Flashcards
(129 cards)
Experimentation
-an approach to research best suited for explanation and evaluation.
-a process of observation to be carried out in a situation expressly brought about for that purpose
Experiments involve:
-Taking action
-Observing Consequences
(Especially suited for hypothesis testing)
Central Features of the Classical Experiment
-Variables, Time Order, Measures, and Groups
Three Pairs of Components of classical experiments
-Independent and dependent variables
-Pretesting and post testing
-experimental and control groups
The outcome, or the effect we expect to see depends on
the independent variable
The Independent Variable
Takes the form of a stimulus that is either present or absent. “The Cause”
The Dependent Variable
The outcome, the effect we expect to see. Depends on the independent variable.
Pretested
Subjects are initially measured in terms of the dependent variable prior to association with the independent variable
Posttesting
Subjects are remeasured in terms of the dependent variable. Differences noted attributed to influence of independent variable
Experimental Group
Exposed to whatever treatment, policy, or initiative we are testing
Control Group
Very similar to experimental group, except that they are NOT exposed.
Hawthorne Effect
Pointed to necessity of control groups
Independent: improved working conditions (better lighting)
Dependent: improvement of employee satisfaction and productivity
Workers were responding more to the attention than to the improved working conditions
Placebo
Ensures that changes in the Dependent Variable actually result from the Independent Variable and are not psychologically based
Double-Blind Experiment
Neither the subjects nor the experimenters know which is the experiment group and which is the control group
Cardinal Rule
Ensure that Experimental and Control groups are as similar as possible
Selecting Subjects
- Decide on target population
- How to select particular members from that group for your experiment
(Randomization)
Randomization
Central Feature of the classical experiment to get statistically equivalent groups
Threats to Internal Validity
Conclusions drawn from experimental results may not reflect what went on in the experiment
History
External events may occur during the course of the experiment
Maturation
People constantly are growing
Testing
The process of testing and retesting
Instrumentation
Changes in the measurement process
Statistical Regression
Extreme scores regress to the mean
Selection biases
The way in which subjects are chosen (use random assignment)