what are the two different types of hypothesis and explain them
what are the two different types of alternative hypothesis and explain them
-directional: a relationship/direction is shown (better/worse), tends to be used when there has already been a range of research carried out relating to the researcher’s investigation
- non-directional: states there is a correlation or direction but doesn’t specify
what is an independent variable
something the researcher changes or manipulates to observe effects . It is generally the cause of effect, has an effect on the DV
what is a dependant variable
something that is measured to see if there is any change. Generally described as the outcome/effect. The IV is a cause that has an effect on the DV
- must be measured using quantitative data
what does the term operationalisation mean
when the researcher clearly defines the variables in terms of how they are being measured. (more specific)
what is an extraneous variable
a variable that can effect the dependant variable unless it’s controlled. These are factors that can affect the results of the experiment
- e.g time of day- some ppts may be ‘morning ppl’ so more alert compared to others
- temperature- too hot/cold may affect ppt performance on task
- if extraneous variables are not controlled they can become confounding variables
what is a cofounding variable
a variable that has an effect on the DV. Unlike the extraneous variable, confounding variables do change systematically with the IV, e.g if time is too early, ppts won’t be fully concentrated as they r too sleepy
what are demand characteristics
what is the investigator effects
what does the term standardisation mean
define the term randomisation
what is a repeated measures design
what is an independent measures design
what is matched pairs design
what are the strengths of a repeated measures design
what are the limitations of a repeated measures design
what are the strengths of an independent group designing
what are the limitations of an independent group design
what are the strengths of matched pair design
what are the limitations of matched pairs design
define a laboratory experiment
what are the strengths and weaknesses of a lab experiment
strengths:
- highly controlled over confounding variables
- easier to establish cause and effect relationships, high internal validity
-highly replicable, standardised procedure
weaknesses:
- demand characteristics, ppts aware they are taking part in study
- low ecological validity- tasks aren’t reflective of everyday, artificial tasks
define a field experiment
what are the strengths and weaknesses of a field experiment
strengths:
- less chance of demand characteristics, increasing validity
- higher ecological validity, degree of artificiality is reduced
weaknesses:
-difficult to replicate
-no control over extraneous or confounding variables, reliability is reduced
- not ethical, lack of consent and deception