Upgrade to remove ads
Only $35.99/year

Chapter 11 Vocabulary

Terms in this set (21)

experiment
An experiment manipulates factor levels to create treatments, randomly assigns subjects to these treatment levels, and then compares the responses of the subject groups across treatment levels
random assignment
To be valid, an experiment must assign experimental units to treatment groups at random.
factor
A variable whose levels are manipulated by the experimenter in an attempt to discover any effects that the factor levels may have on the response variable
response
A variable whose values are compared across difference treatments. In a randomized experiment, large response differences can be attributed to the effect of differences in treatment level.
experimental units
Individuals on whom an experiment is performed. Usually called subjects or participants when they are human.
level
The specific values that the experimenter chooses for a factor are called levels of the factor.
treatment
The process applied to randomly assigned experimental units. Treatment are the different levels of the factor
principals of experimental design
Control aspects of the experiment that we know may have an effect on the response
Randomize subjects to treatments to even out the effects that we cannot control
Replicate over as many subjects as possible.
statistically significant
When an observation difference is too large for us to believe that it is likely to have occurred by chance, we consider the difference to be statistically significant.
control group
The experimental units assigned to a baseline treatment level, or a placebo treatment. Their responses provide a basis for comparison.
blinding
Any individual associated with an experiment who is not aware of how subjects have been allocated to treatment groups is said to be blinded.
single-blind
double-blind
There are two main classes of individuals who can affect the outcome on and experiment
Those who could influence the results
Those who evaluate the results
When every individual in one of these groups is blinded, and experiment is said to be single-blinded. When everyone in both groups is blinded the experiment is double blinded.
placebo
A treatment known to have no effect, administered so that all groups experience the same conditions.
placebo effect
The tendency of many human subjects to show a response even when given a fake treatment.
blocking
When there are pre-existing differences among groups of experimental units, it is often a good idea to gather them together in blocks. By blocking, we isolate the differences so that we can see the effects of the treatments more clearly.
Recommended textbook explanations

Understanding Psychology

2nd EditionMcGraw-Hill Education
903 explanations

Psychology

2nd EditionKatherine Minter, Mary Spilis, William Elmhorst
841 explanations

Psychology

11th EditionC. Nathan DeWall, David G Myers
359 explanations

Psychology

12th EditionC. Nathan DeWall, David G Myers
366 explanations