Research Designs
Case Study
- Case study: brings together wide range of information on single individual or group, including interviews, observations, or test scores
- Best used to study unique type of individuals
- May be influences by researcher biases
- Findings may not generalize
Ethnography
- Ethnography: participant observation of a culture or distinct social group
- Mix of observations, self-reports, interpretation by investigator
- Results can be biased by the researcher
- Findings are limited to the individuals and settings studied
Correlation Design
- Correlational research: researchers gather information and look at the relationship between 2 more naturally occurring characteristics, behaviors, or ideas (ie variables)
- Correlation is not causation
- The strength and direction of the relationship is important
- Correlation coefficient: a number from -1 to +1 that indicates the strength and direction of the relationship between variables
- Direction: the sign +/- of the correlation coefficient indicates the direction of the relationship
- Strength: the closer the number is to +1 or -1, the more strongly related the variables
- Positive correlation: the variables move in the same direction
- Negative correlation: the variables move in opposite directions
Experimental Design
- Experimental design: investigates cause and effect relationships
- Manipulate variables to determine change, as well as cause and effect
- Control as many aspects of the situation as possible (internal validity), in order to generalize the results (external validity)
- Independent variable: the variable the investigator expects to cause changes in another variable
- What is being manipulated
- Dependent variable: the variable being measured
- The outcome
Longitudinal Design
- Longitudinal design: gathers data from one group of individuals at several points of time
- Gives us the clearest picture of how the variables we’re interested in change as a function of age
- One of the biggest threats is attrition