research methods

experimental method

manipulation of an independant variable to have an effect on the dependant variable whcich is measured and stated in results

types of experiments

field

lab

natural

quasi

aims

statement made by the researcher which tells us what they plan on investigating and the purpose of their study

hypothesis

precise statement that clearly states the relationship between the variables being investigated

directional hypothesis

states the direction of the relationship that will be shown

non directional hypothesis

does not predict or show the direction of the relationship

when are directional hypothesis used

when there has already been a range of research and the data would suggest a particular outcome

independant variables

aspect of the experiment which has been manipulated or changes to have an effect on the dv

dependant variable

aspect of study that is measured by research and changes depending on the iv

operationalisation

act of a researcher clearly defining variables in terms of how they are being measured

extraneous variables

any other variable that affects the dv that is not the iv

cofounding variable

variable other than iv that has effect on dv

demand characteristics

any cue the research may give that makes the participant deel that they can guess the aim of the investigation

investigator effects

any unwanted influence from the researches behaviour on the dv

randomisation

use of chance to reduce the effects of bias from investigator effects

standardisation

using the same procedures and instructions for every single participant

lab experiment

takes place in a special environment whereby the variables can be carefully controlled

lab strength

high degree of control

results are replicable

lab cons

experimenter bias

low ecological validity

field experiment

condicted in a natural environment (outside of a lab) but with variables still being controlled

field experiment pros