Research methods Flashcards
what are the 4 types of experiments
- lab
- field
- natural
- quasi
description of lab experiments
- a research method where the experiment manipulates one or more IV
- measures the effects on the dependent variable, under controlled condition
strengths of lab experiments
- tighter control of variables
- easy to comment on cause and effect
- easy to replicate as highly controlled
limitations of lab experiments
- lacks ecological validity
- demand characteristics might also become a problem
description of field experiment
- a natural setting away from a lab
- researcher has less control and can only control the environment to some extent
- collects quantitative data
- extraneous variables are included in the experiment
strengths of field experiments
- higher ecological validity
- participants less likely to show demand characteristics
- high levels of mundane realism
limitations of field experiments
- harder to randomly assign p’s so more likely to be a change
- hard to control extraneous variables
description of natural experiments
the study of a naturally occurring situation as it unfolds in the real world so the researcher does not exert any influence
strengths of a natural experiment
- high ecological validity
- the IV cannot be manipulated for ethical or practical reasons
- little bias from sampling or demand characteristics
limitations of natural experiments
- difficult to create cause and effect relationship due to lack of control
- difficult to replicate
- many extraneous variables
- p’s could become aware of the study causing demand characteristics
description of quasi experiment
- have an IV based on an existing difference between people and no one has manipulated this variable
- the variables just simplely ‘exist’ e.g. being olf or young
strengths of quasi experiemnts
- carried out under a controlled condition
- can be replicated
limitations of quasi experiments
- cannot randomly allocate ps so often are confounding variables
- cannot create a cause and effect relationship as it IV has not been deliberately changed
key point of lab experiments
highly controlled conditions
key point of field experiments
- it takes in a real-world setting
- the experimenter manipulates one or more IV to get a change in DV
key point of natural experiments
- happens without the effect of a researcher
- ecologically valid
- many extraneous variables that cannot be controlled
key point of quasi experiments
variables just simply exist, IV based on an existing difference between people
what is a research aim
the stated intention of what questions are planned to be answered
what is an operational definition
a description of a variable given in terms of how it is actually measured
what is an experimental hypothesis
a statement which makes certain predictions about what results will be during the investigation
what is a null hypothesis
a prediction that nothing will happen
what is a one tailed/directional hypothesis
when a hypothesis predicts the direction of the results
what is a two-tailed or non-directional hypothesis
a hypothesis that does not state a direction but states that there will be a difference between 2 sets of scores
what are extraneous variables
any variables, other than the IV, that may affect the DV if it not controlled