Field experiment
Research aim:
- Identify what type of advertisement increases consumers participation in
environmental conversation.
- Which reference group should be the advertisement use to increase consumer
participation in environmental conversation.
+ What were they trying to find out?
+ What experimental design was used?
+ How many groups were there?
+ What was the treatment used? Describe the stimuli?
+ Is there any problems with the experimental design? If yes, what would you do?
Research design notation
- O = any formal observation or measurement
- X = exposure to the treatment
- EG = experimental group
- CG = control group
- R = random assignment
- M = matching control
Causal research
- Methods: experiments
- Characteristics: manipulation and control of variables
- Purpose: determine cause and effect relationships
- Eg: will increasing the price of products increase profitability?
- Definition: change in a variable produce a change in another variable (independent
variable dependent variable)
- Association does not imply causation
- Three conditions for causality:
+ evidence pf association between X and Y
+ X must occur before Y
+ absence of competing explanations
Controlling extraneous variables
- Design or physical control
+ only differences between groups are manipulated
- Randomization
+ random assignment of test units to groups
+ ensures prior equality of experimental groups
- Statistical control
+ measure and adjust for extraneous variables
Reliability
- Extent to which we can be certain that the observed score is free from random error
- Consistency in results (Will I get the same result of I measured again?)
Internal and External Validity
-
Internal validity: the extent to which the observed results are due to the
experimental manipulation
- External validity: the extent to which the observed results are likely to hold beyond
the experimental setting
Classical vs Statistical Designs
- Classical: one treatment level/ one independent variable
eg: sales response when I lower the price by 10%
- Statistical: different treatment levels/ more than one independent variable
eg: sales response when I lower the price by 10%/ 20%/ 30%
eg: sales response when I lower price and increase advertising
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